Updated: 17 June 2020
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| Tropical Cyclones
[Index] | Tropical Cyclone GIOVANNA : JTWC Advisories |
| Season 2011-2012 Summaries (Operational Data): [AU] [SIO] [SPAC] [SH] | |
| ---> Tropical Cyclone GIOVANNA Track Map and Data |
WTXS21 PGTW 20120208 23:30z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
200 NM EITHER SIDE OF A LINE FROM 12.9S 69.9E TO 15.8S 60.8E WITHIN
THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY ISSUANCE OF
NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME. WINDS IN THE AREA
ARE ESTIMATED TO BE 28 TO 32 KNOTS. METSAT IMAGERY AT 081930Z
INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 13.2S 69.1E. THE
SYSTEM IS MOVING WESTWARD AT 07 KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 13.0S
69.1E, IS NOW LOCATED NEAR 14.0S 67.0E, APPROXIMATELY 480 NM SOUTH-
SOUTHWEST OF DIEGO GARCIA. RECENT ANIMATED INFRARED (IR) SATELLITE
IMAGERY SHOWS SIGNIFICANT IMPROVEMENT IN THE CONSOLIDATION OF THE
LOW LEVEL CIRCULATION CENTER (LLCC). BANDING CONVECTION HAS BEGUN TO
DEVELOP AROUND THE LLCC, WITH DEEPER CONVECTION PERSISTING OVER THE
LLCC. A RECENT 082123Z AMSU-B PASS SUPPORTS THE BANDING OBSERVED IN
IR IMAGERY. UPPER-LEVEL ANALYSIS INDICATES THE DISTURBANCE IS
APPROXIMATELY 05 DEGREES EQUATORWARD OF THE SUBTROPICAL RIDGE AXIS
UNDER WEAK (10-15 KNOT) VERTICAL WIND SHEAR WITH GOOD DIVERGENCE
ALOFT. SEA SURFACE TEMPERATURES IN THE AREA ARE APPROXIMATELY 28-29
DEGREES CELSIUS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 28
TO 32 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1002
MB. DUE TO THE IMPROVING IR SATELLITE SIGNATURE, FAVORABLE SURFACE
CONDITIONS AND GOOD UPPER-LEVEL OUTFLOW PATTERN DEVELOPING, THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
092330Z.//
=========================================================================
WTXS31 PGTW 20120209 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (TWELVE) WARNING NR 001//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/082321ZFEB2012//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.//
RMKS/
1. TROPICAL CYCLONE 12S (TWELVE) WARNING NR 001
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
091200Z --- NEAR 14.1S 65.1E
MOVEMENT PAST SIX HOURS - 265 DEGREES AT 09 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 14.1S 65.1E
---
FORECASTS:
12 HRS, VALID AT:
100000Z --- 14.6S 63.3E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 255 DEG/ 08 KTS
---
24 HRS, VALID AT:
101200Z --- 15.0S 61.8E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 250 DEG/ 07 KTS
---
36 HRS, VALID AT:
110000Z --- 15.5S 60.4E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 245 DEG/ 08 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
111200Z --- 16.2S 58.8E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 255 DEG/ 07 KTS
---
72 HRS, VALID AT:
121200Z --- 17.0S 56.0E
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 255 DEG/ 10 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
131200Z --- 17.9S 51.9E
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 265 DEG/ 12 KTS
---
120 HRS, VALID AT:
141200Z --- 18.3S 47.0E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
091500Z POSITION NEAR 14.2S 64.7E.
TROPICAL CYCLONE (TC) 12S, LOCATED APPROXIMATELY 690 NM NORTHEAST OF
LA REUNION, HAS TRACKED WESTWARD AT 09 KNOTS OVER THE PAST SIX
HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) INDICATES THAT
THE SYSTEM HAS CONSOLIDATED QUICKLY WITH IMPROVED CONVECTIVE BANDING
WRAPPING INTO THE CENTER. A 091155Z 85 GHZ SSMI IMAGE CONFIRMS THE
IMPROVED ORGANIZATION AND SHOWS TIGHTLY-CURVED BANDING WRAPPING INTO
A WELL-DEFINED LOW-LEVEL CIRCULATION CENTER (LLCC). ANIMATED WATER
VAPOR IMAGERY SHOWS IMPROVING RADIAL OUTFLOW WITH ENHANCED POLEWARD
OUTFLOW INTO AN APPROACHING DEEP UPPER-LEVEL TROUGH. THE CURRENT
POSITION IS BASED ON THE SSMI IMAGE AND MSI WITH GOOD CONFIDENCE.
THE CURRENT INTENSITY IS BASED ON DVORAK ESTIMATES OF 35 KNOTS FROM
ALL AGENCIES. TC 12S IS CURRENTLY TRACKING WESTWARD ALONG THE
NORTHERN EDGE OF A DEEP SUBTROPICAL RIDGE (STR) BUT IS FORECAST TO
TURN WEST-SOUTHWESTWARD AS A MIDLATITUDE SHORTWAVE TROUGH PROPAGATES
SOUTH OF THE SYSTEM. IN GENERAL, MODEL GUIDANCE IS POORLY
INITIALIZING THE CURRENT INTENSITY; THEREFORE, A SHARPER TURN
SOUTHWESTWARD, CLOSER TO MAURITIUS, AND GREATER INTERACTION WITH THE
TROUGH IS LIKELY. THIS POLEWARD TURN IS EXPECTED TO BE SHORT-LIVED
AS THE TROUGH MOVES EAST AND A STR BUILDS INTO SOUTHERN MADAGASCAR
PROVIDING A WESTWARD STEERING INFLUENCE. TC 12S IS FORECAST TO
INTENSIFY TO A PEAK INTENSITY OF 90 KNOTS BY TAU 96 DUE TO THE
FAVORABLE ENVIRONMENT. DYNAMIC MODEL GUIDANCE IS LIMITED TO NOGAPS,
GFS, UKMO AND ECMWF; HOWEVER, ONLY NOGAPS AND ECMWF OFFER A
REASONABLE SOLUTION. BOTH UKMO AND GFS MAINTAIN WEAK SYSTEMS AND
INDICATE UNLIKELY TRACKS. UKMO SHOWS A SLOW TRACK THEN EQUATORWARD
TRACK AFTER TAU 48 WHILE GFS SHOWS A WESTWARD TRACK DESPITE ALSO
INDICATING THE DEEP TROUGH PASSING TO THE SOUTH. THE JTWC FORECAST
FAVORS THE NOGAPS/ECMWF SOLUTIONS. THIS WARNING SUPERSEDES AND
CANCELS REF A, JOINT TYPHOON WRNCEN 082321Z FEB 12 TROPICAL CYCLONE
FORMATION ALERT (WTXS21 PGTW 082330). MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 091200Z IS 8 FEET. NEXT WARNINGS AT 100300Z AND 101500Z.//
=========================================================================
WTXS31 PGTW 20120210 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 002//
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 002
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
100000Z --- NEAR 14.7S 63.8E
MOVEMENT PAST SIX HOURS - 235 DEGREES AT 11 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
REPEAT POSIT: 14.7S 63.8E
---
FORECASTS:
12 HRS, VALID AT:
101200Z --- 15.4S 62.1E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT
125 NM SOUTHEAST QUADRANT
105 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 250 DEG/ 09 KTS
---
24 HRS, VALID AT:
110000Z --- 16.0S 60.4E
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
135 NM SOUTHEAST QUADRANT
115 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 250 DEG/ 08 KTS
---
36 HRS, VALID AT:
111200Z --- 16.5S 58.8E
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
135 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 255 DEG/ 08 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
120000Z --- 16.9S 57.1E
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
135 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 265 DEG/ 09 KTS
---
72 HRS, VALID AT:
130000Z --- 17.3S 53.2E
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 260 DEG/ 09 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
140000Z --- 17.8S 49.6E
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 250 DEG/ 12 KTS
---
120 HRS, VALID AT:
150000Z --- 19.5S 45.0E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
100300Z POSITION NEAR 14.9S 63.4E.
TROPICAL CYCLONE (TC) 12S (GIOVANNA), LOCATED APPROXIMATELY 610 NM
NORTHEAST OF LA REUNION, HAS TRACKED SOUTHWESTWARD AT 11 KNOTS OVER
THE PAST SIX HOURS. ANIMATED INFRARED (IR) SATELLITE IMAGERY
INDICATES CONVECTION HAS BEEN BUILDING STEADILY OVER THE PAST 12
HOURS OVER THE LOW LEVEL CIRCULATION CENTER (LLCC). A 092042Z AMSU-B
MICROWAVE PASS SHOWS DEEP TIGHTLY-CURVED BANDING WRAPPING INTO THE
LLCC ALONG THE WESTERN PERIPHERY. ANIMATED WATER VAPOR IMAGERY SHOWS
GOOD RADIAL OUTFLOW EQUATORWARD WITH AN IMPROVING POLEWARD OUTFLOW
CHANNEL SUPPORTED BY A DEEP MID-LATITUDE TROUGH LOCATED TO THE
SOUTHWEST OF TC 12S. THE CURRENT INTENSITY IS BASED ON A
CONSOLIDATION OF DVORAK FIXES FROM PGTW AND KNES. THE CURRENT
POSITION IS BASED ON IR SATELLITE IMAGERY SHOWING OVERSHOOTING TOPS
IN THE DEEPEST CENTRAL CONVECTION AND PGTW/KNES FIXES WITH FAIR
CONFIDENCE. TC 12S HAS BEEN TRACKING ALONG THE NORTHERN EDGE OF A
DEEP SUBTROPICAL RIDGE (STR) BUT HAS RECENTLY TURNED TO THE
SOUTHWEST AS THE APPROACHING MID-LATITUDE TROUGH HAS STARTED TO
ERODE THE WESTERN PERIPHERY OF THE STR. SEA SURFACE TEMPERATURES
(SST) REMAIN VERY FAVORABLE FOR CONTINUED DEVELOPMENT. THE FORECAST
MAINTAINS THE CURRENT TRACK THROUGH TAU 36 AS THE TROUGH TRACKS
EASTWARD, ALLOWING THE STR TO BUILD BACK OVER MADAGASCAR AND
FLATTENING THE TRACK THROUGH TAU 72. LANDFALL IS EXPECTED AROUND TAU
96 WITH ANOTHER TURN TO THE SOUTHWEST AS TC 12S TRACKS OVER
MADAGASCAR. INTENSITY IS EXPECTED TO BUILD THROUGH TAU 84 AS THE SST
VALUES REMAIN VERY FAVORABLE ALONG THE FORECASTED TRACK WITH GOOD
UPPER LEVEL DIVERGENCE. BEYOND TAU 84 INCREASING LAND INTERACTION
WILL CAUSE A SLOW WEAKENING TREND THROUGH LANDFALL, WITH INCREASED
WEAKENING AS TC 12S TRACKS OVER CENTRAL MADAGASCAR. MODEL GUIDANCE
IS IN GOOD AGREEMENT WITH NGPS, GFS, GFDN, AND ECMF ALL SHOWING A
SIMILAR TRACK. THIS FORECAST FAVORS THE CONSENSUS OF ALL AVAILABLE
GUIDANCE. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 100000Z IS 10 FEET.
NEXT WARNINGS AT 101500Z AND 110300Z.//
=========================================================================
WTXS31 PGTW 20120210 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 003//
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 003
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
101200Z --- NEAR 15.6S 61.6E
MOVEMENT PAST SIX HOURS - 255 DEGREES AT 08 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
REPEAT POSIT: 15.6S 61.6E
---
FORECASTS:
12 HRS, VALID AT:
110000Z --- 16.2S 60.1E
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 250 DEG/ 08 KTS
---
24 HRS, VALID AT:
111200Z --- 16.7S 58.5E
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
105 NM SOUTHEAST QUADRANT
105 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 260 DEG/ 07 KTS
---
36 HRS, VALID AT:
120000Z --- 16.9S 57.1E
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT
125 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
115 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 265 DEG/ 08 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
121200Z --- 17.0S 55.4E
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT
125 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
115 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 265 DEG/ 11 KTS
---
72 HRS, VALID AT:
131200Z --- 17.5S 50.9E
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
115 NM SOUTHEAST QUADRANT
115 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 255 DEG/ 11 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
141200Z --- 18.6S 46.3E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 240 DEG/ 12 KTS
---
120 HRS, VALID AT:
151200Z --- 21.0S 42.0E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
101500Z POSITION NEAR 15.8S 61.2E.
TROPICAL CYCLONE (TC) 12S, LOCATED APPROXIMATELY 480 NM NORTHEAST OF
LA REUNION, HAS TRACKED WEST-SOUTHWESTWARD AT 08 KNOTS OVER THE PAST
SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY INDICATES THAT
TC 12S HAS RAPIDLY CONSOLIDATED AND HAS NOW FORMED AN INCIPIENT EYE.
ANIMATED WATER VAPOR IMAGERY INDICATES EXCELLENT RADIAL OUTFLOW WITH
STRONG POLEWARD OUTFLOW ENHANCED BY A DEEP UPPER-LEVEL TROUGH
POSITIONED SOUTHEAST OF MADAGASCAR. CONSEQUENTLY, DVORAK ESTIMATES
HAVE INCREASED TO 65 (PGTW/FMEE) TO 77 KNOTS (KNES). THE CURRENT
INTENSITY WAS ASSESSED AT 65 KNOTS BASED ON THE WEAK EYE IN VISIBLE
IMAGERY AND THE SIGNATURE IN THE 100919Z AMSU IMAGE. THERE IS HIGH
CONFIDENCE IN THE CURRENT POSITION BASED ON THE EYE. TC 12S IS
CURRENTLY TRACKING WEST-SOUTHWESTWARD (WSW) ALONG THE NORTHWESTERN
PERIPHERY OF THE DEEP SUBTROPICAL RIDGE (STR) AS A MIDLATITUDE
SHORTWAVE TROUGH PROPAGATES SOUTH OF THE SYSTEM. THIS WSW TRACK IS
EXPECTED TO BE SHORT-LIVED AS THE TROUGH MOVES EAST AND A STR BUILDS
INTO SOUTHERN MADAGASCAR PROVIDING A WESTWARD STEERING INFLUENCE.
THE AVAILABLE DYNAMIC GUIDANCE IS IN EXCEPTIONALLY TIGHT AGREEMENT
AND SUPPORTS THE JTWC TRACK, WHICH IS POSITIONED VERY CLOSE TO THE
MODEL CONSENSUS AS WELL AS THE ECMWF MODEL. DUE TO THE FAVORABLE
ENVIRONMENT, TC 12S IS FORECAST TO STRENGHTHEN TO A PEAK OF 110
KNOTS WITHIN THE NEXT 36 HOURS. THE SYSTEM IS EXPECTED TO WEAKEN
SIGNIFICANTLY AS IT TRACKS ACROSS MADAGASCAR; HOWEVER, RE-
DEVELOPMENT IS EXPECTED IN THE MOZAMBIQUE CHANNEL AFTER TAU 120.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 101200Z IS 15 FEET. NEXT WARNINGS
AT 110300Z AND 111500Z.//
=========================================================================
WTXS31 PGTW 20120210 21:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 004//
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 004
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
101800Z --- NEAR 16.0S 61.0E
MOVEMENT PAST SIX HOURS - 235 DEGREES AT 07 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
105 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
REPEAT POSIT: 16.0S 61.0E
---
FORECASTS:
12 HRS, VALID AT:
110600Z --- 16.4S 59.5E
MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
105 NM SOUTHEAST QUADRANT
115 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 260 DEG/ 08 KTS
---
24 HRS, VALID AT:
111800Z --- 16.7S 57.9E
MAX SUSTAINED WINDS - 130 KT, GUSTS 160 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
115 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 265 DEG/ 07 KTS
---
36 HRS, VALID AT:
120600Z --- 16.8S 56.5E
MAX SUSTAINED WINDS - 135 KT, GUSTS 165 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 075 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
130 NM SOUTHWEST QUADRANT
115 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 265 DEG/ 09 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
121800Z --- 16.9S 54.6E
MAX SUSTAINED WINDS - 130 KT, GUSTS 160 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT
125 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
115 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 260 DEG/ 10 KTS
---
72 HRS, VALID AT:
131800Z --- 17.6S 50.3E
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
115 NM SOUTHEAST QUADRANT
115 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 250 DEG/ 11 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
141800Z --- 18.9S 46.0E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 230 DEG/ 15 KTS
---
120 HRS, VALID AT:
151800Z --- 22.5S 41.1E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
102100Z POSITION NEAR 16.1S 60.6E.
TROPICAL CYCLONE 9TC 12S (GIOVANNA), LOCATED APPROXIMATELY 432 NM
NORTHEAST OF LA REUNION, HAS TRACKED SOUTHWESTWARD AT 07 KNOTS OVER
THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY SHOWS THE
SYSTEM HAS RAPIDLY DEEPENED AND CONSOLIDATED AROUND A PIN-HOLE EYE
WHILE MAINTAINING A HIGHLY-SYMMETRICAL AND COMPACT BANDING. WATER
VAPOR ANIMATION DISPLAYS EXCELLENT RADIAL OUTFLOW WITH A VERY
EFFICIENT POLEWARD CHANNEL. THE INITIAL POSITION IS PLACED OVER THE
EYE FEATURE WITH HIGH CONFIDENCE AND THE INITIAL INTENSITY IS
SUPPORTED BY DVORAK ESTIMATES FROM FMEE (115 KTS), PGTW (115 KTS)
AND KNES (110 KTS). UPPER LEVEL ANALYSIS INDICATES TC 12S IS IN A
VERY FAVORABLE ENVIRONMENT OF LOW VERTICAL WIND SHEAR IN A DIFFLUENT
ZONE UNDER A RIDGE AXIS. IT IS EXPECTED TO CONTINUE TRACKING ALONG
THE NORTHWEST PERIPHERY OF A DEEP-LAYERED SUBTROPICAL RIDGE (STR) TO
THE SOUTHEAST. AFTER TAU 48, AN EXTENSION OF A SECONDARY STR
CURRENTLY ANCHORED OVER MOZAMBIQUE WILL ASSUME STEERING. THE
TRANSITION WILL BE SEAMLESS AND WILL MERELY CAUSE A SLIGHT
FLATTENING OF THE FORECAST TRACK. GIOVANNA WILL CONTINUE TO
INTENSIFY OVER THE NEXT 48 HOURS PEAKING AT 135 KNOTS BEFORE MAKING
LANDFALL IN MADAGASCAR AND EXITING INTO THE MOZAMBIQUE CHANNEL AFTER
TAU 96. THE AVAILABLE NUMERICAL GUIDANCE IS IN VERY TIGHT AGREEMENT
WITH THIS TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 101800Z
IS 25 FEET. NEXT WARNINGS AT 110300Z, 111500Z AND 120300Z.//
=========================================================================
WTXS31 PGTW 20120211 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 005//
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 005
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
110000Z --- NEAR 16.7S 60.1E
MOVEMENT PAST SIX HOURS - 230 DEGREES AT 11 KTS
POSITION ACCURATE TO WITHIN 025 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
REPEAT POSIT: 16.7S 60.1E
---
FORECASTS:
12 HRS, VALID AT:
111200Z --- 17.5S 58.8E
MAX SUSTAINED WINDS - 125 KT, GUSTS 150 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
105 NM SOUTHEAST QUADRANT
115 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 265 DEG/ 07 KTS
---
24 HRS, VALID AT:
120000Z --- 17.6S 57.4E
MAX SUSTAINED WINDS - 130 KT, GUSTS 160 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
115 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 270 DEG/ 09 KTS
---
36 HRS, VALID AT:
121200Z --- 17.6S 55.6E
MAX SUSTAINED WINDS - 135 KT, GUSTS 165 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 075 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
130 NM SOUTHWEST QUADRANT
115 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 260 DEG/ 12 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
130000Z --- 17.9S 53.2E
MAX SUSTAINED WINDS - 130 KT, GUSTS 160 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT
125 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
115 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 255 DEG/ 11 KTS
---
72 HRS, VALID AT:
140000Z --- 18.8S 48.7E
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 96 HR POSIT: 245 DEG/ 13 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
150000Z --- 20.8S 43.7E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 245 DEG/ 12 KTS
---
120 HRS, VALID AT:
160000Z --- 22.7S 38.9E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
110300Z POSITION NEAR 16.9S 59.8E.
TROPICAL CYCLONE (TC) 12S (GIOVANNA), LOCATED APPROXIMATELY 365 NM
NORTHEAST OF LA REUNION, HAS TRACKED SOUTHWESTWARD AT 11 KNOTS OVER
THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY SHOWS THE
SYSTEM HAS MAINTAINED DEEP, HIGHLY-SYMMETRICAL AND VERY COMPACT
CONVECTIVE BANDING AROUND A 15-NM DIAMETER EYE. RECENT WATER VAPOR
SATELLITE ANIMATION DISPLAYS EXCELLENT RADIAL OUTFLOW WITH A VERY
EFFICIENT POLEWARD CHANNEL. THE INITIAL POSITION IS PLACED OVER THE
EYE FEATURE WITH HIGH CONFIDENCE AND THE INITIAL INTENSITY IS
SUPPORTED BY DVORAK ESTIMATES FROM FMEE, PGTW AND KNES. UPPER LEVEL
ANALYSIS INDICATES TC 12S IS IN A VERY FAVORABLE ENVIRONMENT OF LOW
VERTICAL WIND SHEAR IN A DIFFLUENT ZONE UNDER A RIDGE AXIS. IT IS
EXPECTED TO CONTINUE TRACKING ALONG THE NORTHWEST PERIPHERY OF A
DEEP-LAYERED SUBTROPICAL RIDGE (STR) TO THE SOUTHEAST. AFTER TAU 12,
AN EXTENSION OF A SECONDARY STR CURRENTLY ANCHORED OVER MOZAMBIQUE
CHANNEL WILL ASSUME STEERING. THE TRANSITION WILL CAUSE A SLIGHTLY
MORE WESTWARD DIRECTION IN THE FORECAST TRACK. TC GIOVANNA WILL
CONTINUE TO INTENSIFY OVER THE NEXT 48 HOURS PEAKING AT 135 KNOTS
BEFORE MAKING LANDFALL IN MADAGASCAR AND EXITING INTO THE MOZAMBIQUE
CHANNEL JUST BEFORE TAU 96. THE AVAILABLE NUMERICAL GUIDANCE IS IN
VERY TIGHT AGREEMENT WITH THIS TRACK FORECAST WITH WBAR AS THE SOLE
LEFT OUTLIER AFTER TAU 36. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
110000Z IS 26 FEET. NEXT WARNINGS AT 111500Z AND 120300Z.//
=========================================================================
WTXS31 PGTW 20120211 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 006//
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 006
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
111200Z --- NEAR 17.2S 59.0E
MOVEMENT PAST SIX HOURS - 240 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
REPEAT POSIT: 17.2S 59.0E
---
FORECASTS:
12 HRS, VALID AT:
120000Z --- 17.4S 57.7E
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 265 DEG/ 08 KTS
---
24 HRS, VALID AT:
121200Z --- 17.5S 56.0E
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
115 NM SOUTHEAST QUADRANT
115 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 260 DEG/ 11 KTS
---
36 HRS, VALID AT:
130000Z --- 17.8S 53.8E
MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 260 DEG/ 12 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
131200Z --- 18.1S 51.4E
MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 260 DEG/ 14 KTS
---
72 HRS, VALID AT:
141200Z --- 19.2S 45.7E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 96 HR POSIT: 245 DEG/ 13 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
151200Z --- 21.4S 40.8E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 240 DEG/ 08 KTS
---
120 HRS, VALID AT:
161200Z --- 23.0S 38.0E
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
111500Z POSITION NEAR 17.2S 58.7E.
TROPICAL CYCLONE (TC) 12S (GIOVANNA), LOCATED APPROXIMATELY 290 NM
NORTHEAST OF LA REUNION, HAS TRACKED WEST-SOUTHWESTWARD AT 04 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
(MSI) SHOWS THAT THE PREVIOUS PINHOLE-SIZED EYE HAS NOW BECOME A
LARGER, APPROXIMATELY 35 NM WIDE EYE. BD ENHANCED INFRARED SATELLITE
IMAGERY FROM THE PAST SIX HOURS SHOWS THAT THE COLDEST CLOUD TOPS
ARE NOW FOUND FARTHER AWAY FROM THE EYE. COMPARISON OF THE 110347Z
TRMM 85 GHZ TO THE 111119Z AMSU-B 89 GHZ IMAGE CLEARLY SHOWS THAT TC
12S HAS UNDERGONE, AND COMPLETED, AN EYEWALL REPLACEMENT CYCLE
(ERC). THE TRMM IMAGE SHOWS DEEP CONVECTION ENCIRCLING THE SMALLER
EYEWALL CONVECTION AND THE AMSU-B IMAGE INDICATES THAT THE DEEP
CONVECTION IS NOW CONTAINED TO THAT OUTER RING OF CONVECTION, WHICH
IS NOW THE NEW, LARGER, EYEWALL. IT SEEMS THAT SHORTLY AFTER TC
GIOVANNA UNDERWENT RAPID INTENSIFICATION THE OUTER RING OF DEEP
CONVECTION BEGAN TO FORM. THE ERC TOOK APPROXIMATELY 10 HOURS FROM
ANALYSIS OF PAST MICROWAVE IMAGES. THE CURRENT POSITION IS BASED ON
THE VISIBLE EYE IN MSI WITH HIGH CONFIDENCE. THE CURRENT INTENSITY
IS BASED ON DVORAK ESTIMATES OF 102 KNOTS FROM PGTW, KNES, AND FMEE.
UPPER-LEVEL ANALYSIS INDICATES THAT TC 12S IS UNDER A SELF-INDUCED
MESO-ANTICYCLONE PROVIDING WEAK VERTICAL WIND SHEAR (VWS) AND GOOD
DIVERGENCE ALOFT. TC 12S IS CURRENTLY TRACKING UNDER THE INFLUENCE
OF THE NORTHWESTERN PERIPHERY OF A DEEP-LAYERED SUBTROPICAL RIDGE
(STR) CENTERED TO THE SOUTHEAST. ADDITIONALLY, A MID- TO UPPER-LEVEL
TROUGH IS PROPAGATING TO THE SOUTHEAST AND MOMENTARILY CREATING A
SLIGHT WEAKNESS IN THE WESTERN EXTENT OF THE STR. HOWEVER, A NEW STR
IS BUILDING IN SOUTH-SOUTHEAST OF MADAGASCAR AND WILL BECOME THE
STEERING INFLUENCE AFTER ABOUT 18-24 HOURS. TC GIOVANNA WILL TRACK
GENERALLY WESTWARDS AND MAKE LANDFALL OVER MADAGASCAR IN
APPROXIMATELY THE NEXT 2.5 DAYS. INTENSITY HAS BEEN LOWERED DUE TO
THE RECENT ERC BUT WILL GRADUALLY INCREASE UNDER FAVORABLE
ENVIRONMENTAL CONDITIONS. BY TAU 72, THE LOW LEVEL CIRCULATION
CENTER (LLCC) WILL INTERACT WITH THE VERY RUGGED TOPOGRAPHY THAT
RESIDES IN CENTRAL MADAGASCAR. AFTER A PERIOD OF WEAKENING DUE TO
THE TOPOGRAPHYS FRICTIONAL FORCES, TC 12S WILL EMERGE OVER THE WARM
WATERS OF THE MOZAMBIQUE CHANNEL AND BEGIN TO RE-INTENSIFY. MODEL
GUIDANCE REMAINS IN EXCELLENT AGREEMENT OUT TILL TAU 72. AFTER THE
SYSTEM EMERGES OVER THE CHANNEL THE GUIDANCE BEGINS TO SPREAD DUE TO
DIFFERENT INITIAL POSITIONS AT THIS TIME. LEE-SIDE JUMPS IN THE LLCC
HAVE BEEN NOTED FOR THIS REGION BUT THIS FORECAST FAVORS THE MAIN
PACKING OF THE OBJECTIVE AIDS (NOGAPS, GFS, ECMWF) DURING THIS
TRANSITION. THE OFFICIAL FORECAST LAYS ON THE MODEL CONSENSUS DURING
THE FIRST 48 HOURS, AFTER WHICH, THEN FAVORS THE PREVIOUSLY
MENTIONED MAIN GROUPING. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 111200Z
IS 22 FEET. NEXT WARNINGS AT 120300Z AND 121500Z.//
=========================================================================
WTXS31 PGTW 20120212 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 007//
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 007
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
120000Z --- NEAR 17.5S 57.9E
MOVEMENT PAST SIX HOURS - 260 DEGREES AT 05 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
REPEAT POSIT: 17.5S 57.9E
---
FORECASTS:
12 HRS, VALID AT:
121200Z --- 17.6S 56.3E
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 265 DEG/ 11 KTS
---
24 HRS, VALID AT:
130000Z --- 17.7S 54.0E
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
115 NM SOUTHEAST QUADRANT
115 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 260 DEG/ 12 KTS
---
36 HRS, VALID AT:
131200Z --- 18.0S 51.5E
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 265 DEG/ 13 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
140000Z --- 18.3S 48.8E
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 72 HR POSIT: 245 DEG/ 14 KTS
---
72 HRS, VALID AT:
150000Z --- 20.7S 43.5E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 250 DEG/ 10 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
160000Z --- 22.1S 39.5E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 255 DEG/ 06 KTS
---
120 HRS, VALID AT:
170000Z --- 22.7S 37.1E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
120300Z POSITION NEAR 17.5S 57.5E.
TROPICAL CYCLONE (TC) 12S (GIOVANNA), LOCATED APPROXIMATELY 260 NM
NORTH-NORTHEAST OF LA REUNION, HAD TRACKED WEST-SOUTHWESTWARD AT 05
KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY
SHOWS THE SYSTEM HAS MAINTAINED DEEP CONVECTIVE BANDING AROUND A
WELL-DEFINED, ALBEIT CLOUD-FILLED EYE. RECENT WATER VAPOR SATELLITE
ANIMATION SHOWS EXCELLENT RADIAL OUTFLOW ESPECIALLY ON THE POLEWARD
SIDE. THE INITIAL POSITION IS PLACED OVER THE MICROWAVE EYE IN THE
112203Z AMSU-B IMAGE. THE INITIAL INTENSITY IS SUPPORTED BY DVORAK
ESTIMATE OF 102 KNOTS FROM PGTW. UPPER LEVEL ANALYSIS INDICATES TC
12S REMAINS IN A VERY FAVORABLE ENVIRONMENT WITH LOW VERTICAL WIND
SHEAR IN A DIFFLUENT ZONE JUST TO THE SOUTHWEST OF A RIDGE AXIS.
A SUBTROPICAL RIDGE EXTENDED WEST-EAST OVER SOUTHERN MADAGASCAR HAS
ASSUMED STEERING OF THE SYSTEM, ACCOUNTING FOR A FLATTER WESTWARD
MOVEMENT. TC GIOVANNA WILL CONTINUE TO INTENSIFY OVER THE NEXT 24
HOURS, PEAKING AT 110 KNOTS BEFORE MAKING LANDFALL IN MADAGASCAR AND
EXITING INTO THE MOZAMBIQUE CHANNEL JUST BEFORE TAU 72. THE
AVAILABLE NUMERICAL GUIDANCE IS IN VERY TIGHT AGREEMENT WITH THIS
TRACK FORECAST WITH WBAR AS THE SOLE LEFT OUTLIER. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 120000Z IS 24 FEET. NEXT WARNINGS AT
121500Z AND 130300Z.//
=========================================================================
WTXS31 PGTW 20120212 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 008//
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 008
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
121200Z --- NEAR 17.7S 56.6E
MOVEMENT PAST SIX HOURS - 265 DEGREES AT 10 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 110 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT
200 NM SOUTHEAST QUADRANT
190 NM SOUTHWEST QUADRANT
170 NM NORTHWEST QUADRANT
REPEAT POSIT: 17.7S 56.6E
---
FORECASTS:
12 HRS, VALID AT:
130000Z --- 17.9S 54.2E
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 110 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT
200 NM SOUTHEAST QUADRANT
190 NM SOUTHWEST QUADRANT
170 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 260 DEG/ 12 KTS
---
24 HRS, VALID AT:
131200Z --- 18.2S 51.8E
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 110 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT
200 NM SOUTHEAST QUADRANT
190 NM SOUTHWEST QUADRANT
170 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 260 DEG/ 12 KTS
---
36 HRS, VALID AT:
140000Z --- 18.6S 49.3E
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 100 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT
180 NM SOUTHEAST QUADRANT
145 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 250 DEG/ 13 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
141200Z --- 19.4S 46.7E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 72 HR POSIT: 240 DEG/ 13 KTS
---
72 HRS, VALID AT:
151200Z --- 22.0S 41.9E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 245 DEG/ 08 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
161200Z --- 23.2S 38.9E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 280 DEG/ 09 KTS
---
120 HRS, VALID AT:
171200Z --- 22.5S 35.1E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
121500Z POSITION NEAR 17.7S 56.0E.
TROPICAL CYCLONE (TC) 12S (GIOVANNA), LOCATED APPROXIMATELY 200 NM
NORTH-NORTHEAST OF LA REUNION, HAD TRACKED WESTWARD AT 10
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS THAT TC 12S IS STRUGGLING TO MAINTAIN A CLOUD-FREE
EYE. A 121108Z AMSU-B IMAGE INDICATES AN APPROXIMATELY 35 NM WIDE
EYE. COMPARISON OF THIS AMSU-B IMAGE TO AMSU-B IMAGES IN THE PAST 6-
12 HOURS REVEALS A WEAKENING IN THE DEEP CENTRAL CONVECTION
SURROUNDING THE LOW-LEVEL CIRCULATION CENTER (LLCC). THE CURRENT
POSITION IS BASED ON AGREEABLE PGTW, KNES, FMEE, AND FIMP CENTER
FIXES ALONG WITH THE AMSU-B IMAGE WITH HIGH CONFIDENCE. THE CURRENT
INTENSITY IS BASED ON DVORAK ESTIMATES OF 90-102 KNOTS FROM THESE
REPORTING AGENCIES. UPPER-LEVEL ANALYSIS CONTINUES TO SHOW A SELF-
INDUCED MESO-ANTICYCLONE OVER THE LLCC WHICH IS PRODUCING EXCELLENT
DIVERGENCE ALOFT AND WEAK VERTICAL WIND SHEAR (VWS). ANIMATED WATER
VAPOR IMAGERY ALSO CONTINUES TO SHOW EXCELLENT RADIAL OUTFLOW. TC
GIOVANNA'S TRACK SPEED HAD ACCELERATED OVER THE PAST SIX HOURS AS A
DEEP-LAYERED SUBTROPICAL RIDGE (STR) BUILDS IN FROM THE SOUTH. THE
SYSTEM WILL TRACK WESTWARDS ALONG THE NORTHERN PERIPHERY OF THIS STR
DURING THE NEXT TWO DAYS. DURING THIS TIME TC 12S SHOULD SLIGHTLY
INTENSIFY AS IT MAKES LANDFALL OVER CENTRAL MADAGASCAR JUST AFTER
TAU 36. DURING TAU 48 THE LLCC WILL WEAKEN SIGNIFICANTLY DUE TO THE
FRICTIONAL FORCES OF TOPOGRAPHIC INTERACTION. BY TAU 72 THE SYSTEM
SHOULD EMERGE OVER THE WARM WATERS OF THE MOZAMBIQUE CHANNEL AND
TRACK SOUTHWESTWARDS ALONG THE WESTERN PERIPHERY OF THE STR. BY TAU
96, THE LLCC MAY HEAD TOWARDS A SLIGHT COL REGION IN BETWEEN THE STR
TO THE EAST AND A BUILDING RIDGE OVER SOUTHERN AFRICA. BY TAU 120
THE NEW STEERING INFLUENCE OF THE STR OVER SOUTHERN AFRICA MAY
DEFLECT TC 12S ON A MORE WEST-NORTHWESTWARDS TRACK INTO SOUTHERN
MOZAMBIQUE WHERE THE SYSTEM WILL BEGIN TO DISSIPATE OVERLAND. DURING
ITS TRANSIT OVER THE MOZAMBIQUE CHANNEL THE SYSTEM SHOULD ONLY
SLIGHTLY RE-INTENSIFY DUE TO THE UNFAVORABLE INFLUENCES OF VWS AND
LIMITED TIME OVER WATER. NUMERICAL MODEL GUIDANCE IS IN TIGHT
AGREEMENT UNTIL THE LLCC TRACKS OVER MADAGASCAR AND EMERGES OVER THE
CHANNEL AND IS SPLIT INTO TWO MAIN GROUPINGS. THE ECMWF, NOGAPS, AND
GFS LIE RIGHT OF CONSENSUS AND THE GFDN AND EGRR LIE TO THE LEFT.
THIS FORECAST FAVORS THE FIRST GROUPING TO THE RIGHT OF CONSENSUS
BASED ON MORE MEMBERS AND PAST MODEL PERFORMANCE. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 121200Z IS 26 FEET. NEXT WARNINGS AT
130300Z AND 131500Z.//
=========================================================================
WTXS31 PGTW 20120213 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 009//
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 009
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
130000Z --- NEAR 18.2S 54.1E
MOVEMENT PAST SIX HOURS - 260 DEGREES AT 14 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 125 KT, GUSTS 150 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 115 NM NORTHEAST QUADRANT
125 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
115 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 195 NM NORTHEAST QUADRANT
205 NM SOUTHEAST QUADRANT
220 NM SOUTHWEST QUADRANT
210 NM NORTHWEST QUADRANT
REPEAT POSIT: 18.2S 54.1E
---
FORECASTS:
12 HRS, VALID AT:
131200Z --- 18.5S 51.3E
MAX SUSTAINED WINDS - 130 KT, GUSTS 160 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 115 NM NORTHEAST QUADRANT
125 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
115 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 195 NM NORTHEAST QUADRANT
205 NM SOUTHEAST QUADRANT
220 NM SOUTHWEST QUADRANT
210 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 260 DEG/ 12 KTS
---
24 HRS, VALID AT:
140000Z --- 18.8S 48.8E
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 36 HR POSIT: 250 DEG/ 13 KTS
---
36 HRS, VALID AT:
141200Z --- 19.7S 46.2E
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 48 HR POSIT: 250 DEG/ 13 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
150000Z --- 20.6S 43.5E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 235 DEG/ 10 KTS
---
72 HRS, VALID AT:
160000Z --- 22.8S 39.7E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 265 DEG/ 06 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
170000Z --- 23.0S 37.0E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 120 HR POSIT: 270 DEG/ 06 KTS
---
120 HRS, VALID AT:
180000Z --- 22.9S 34.3E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
130300Z POSITION NEAR 18.3S 53.4E.
TROPICAL CYCLONE (TC) 12S (GIOVANNA), LOCATED APPROXIMATELY 400 NM
EAST OF ANTANANARIVO, MADAGASCAR, HAD TRACKED WEST-SOUTHWESTWARD AT
14 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE
IMAGERY SHOWS THE SYSTEM HAS REINTENSIFIED CONCIDENT WITH THE
EMERGENCE OF A HIGHLY SYMMETRICAL 40-NM DIAMETER EYE. A 130000Z SSMI
MICROWAVE IMAGE SHOWS THE EYE IS ENVELOPED BY A CONTINUOUS RING OF
ULTRA-DEEP CONVECTION, WHICH IS IN TURN SURROUNDED BY A CONCENTRIC
RING OF SHALLOW REFLECTIVITIES, CHARACTERISTIC OF INTENSE ANNULAR
CYCLONES. THE INITIAL POSITION WAS PLACED WITH HIGH CONFIDENCE OVER
THE EYE FEATURE AND THE INITIAL INTENSITY WAS BASED ON DVORAK
ESTIMATES FROM PGTW AND FMEE. UPPER LEVEL ANALYSIS INDICATES THE
CYCLONE HAS FORMED ITS OWN MESOSCALE ANTICYCLONE THAT IS PROVIDING
EXCELLENT RADIAL OUTFLOW. TC 12S IS EXPECTED TO CONTINUE TRACKING
ALONG THE NORTHERN PERIPHERY OF A SUBTROPICAL RIDGE EXTENSION TO THE
SOUTH. IT WILL MAKE LANDFALL OVER THE CENTRAL EASTERN COAST OF
MADAGASCAR SHORTLY BEFORE TAU 24, THEN EXIT INTO THE MOZAMBIQUE
CHANNEL BY TAU 48 BEFORE MAKING A SECONDARY AND FINAL LANDFALL INTO
SOUTHERN MOZAMBIQUE. THE AVAILABLE NUMERICAL GUIDANCE IS IN CLOSE
AGREEMENT WITH THE EXCEPTION OF GFDN THAT BRINGS THE VORTEX POLEWARD
AFTER TAU 72. THIS TRACK FORECAST IS IN LINE WITH CONSENSUS. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 130000Z IS 28 FEET. NEXT WARNINGS AT
131500Z AND 140300Z.//
=========================================================================
WTXS31 PGTW 20120213 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 010//
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 010
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
131200Z --- NEAR 18.7S 51.5E
MOVEMENT PAST SIX HOURS - 250 DEGREES AT 12 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 125 KT, GUSTS 150 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 115 NM NORTHEAST QUADRANT
125 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
115 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 195 NM NORTHEAST QUADRANT
220 NM SOUTHEAST QUADRANT
220 NM SOUTHWEST QUADRANT
195 NM NORTHWEST QUADRANT
REPEAT POSIT: 18.7S 51.5E
---
FORECASTS:
12 HRS, VALID AT:
140000Z --- 19.0S 48.7E
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 255 DEG/ 14 KTS
---
24 HRS, VALID AT:
141200Z --- 19.8S 45.9E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 36 HR POSIT: 240 DEG/ 14 KTS
---
36 HRS, VALID AT:
150000Z --- 21.2S 43.3E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 240 DEG/ 11 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
151200Z --- 22.3S 41.3E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 240 DEG/ 07 KTS
---
72 HRS, VALID AT:
161200Z --- 23.6S 38.8E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 260 DEG/ 03 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
171200Z --- 23.8S 37.3E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 120 HR POSIT: 265 DEG/ 05 KTS
---
120 HRS, VALID AT:
181200Z --- 23.9S 35.0E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
131500Z POSITION NEAR 18.8S 50.8E.
TROPICAL CYCLONE (TC) 12S (GIOVANNA), LOCATED APPROXIMATELY 250 NM
EAST OF ANTANANARIVO, MADAGASCAR, HAD TRACKED WEST-SOUTHWESTWARD AT
12 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) SHOWS AN INTENSE TC WITH AN APPROXIMATELY 30 NM WIDE
EYE AND OUTER FEEDER BANDS CURRENTLY EFFECTING EASTERN MADAGASCAR. A
131232Z SSMI 85 GHZ IMAGE SHOWS AND OUTER RING OF DEEP CONVECTION
SURROUNDING THE INNER EYEWALL CONVECTION. TC 12S IS CLEARLY
UNDERGOING ANOTHER EYEWALL REPLACEMENT CYCLE (ERC) BUT IS ALSO 120
NM AWAY FROM LANDFALL. THE ERC MAY NOT HAVE ENOUGH TIME TO COMPLETE
THE PROCESS. HOWEVER, IF IT DOES, THAN INTENSITIES WOULD BE SLIGHTLY
LOWER AS TC GIOVANNA MAKES LANDFALL, BUT THE RADIUS OF MAXIMUM WINDS
WOULD ALSO INCREASE. THE CURRENT POSITION IS BASED ON THE EYE
FEATURE IN MSI WITH HIGH CONFIDENCE. THE CURRENT INTENSITY IS BASED
ON DVORAK ESTIMATES RANGING FROM 115-127 KNOTS FROM PGTW, KNES,
FMEE, AND FIMP. UPPER-LEVEL ANALYSIS INDICATES THAT TC 12S HAS
MAINTAINED ITS SELF-INDUCED MESO-ANTICYCLONE PROVIDING WEAK VERTICAL
WIND SHEAR (VWS) AND EXCELLENT DIVERGENCE ALOFT. ANIMATED WATER
VAPOR IMAGERY ALSO CONTINUES TO SHOW EXCELLENT RADIAL OUTFLOW. TC
GIOVANNA IS EXPECTED TO CONTINUE TRACKING WESTWARD ALONG THE
NORTHERN PERIPHERY OF A SUBTROPICAL RIDGE EXTENSION LOCATED TO THE
SOUTH. IT WILL MAKE LANDFALL OVER THE CENTRAL EASTERN COAST OF
MADAGASCAR SHORTLY BEFORE TAU 12, THEN WEAKEN DUE TO FRICTIONAL AND
TOPOGRAPHIC DRAG, AND EXIT INTO THE MOZAMBIQUE CHANNEL BY TAU 36
BEFORE MAKING A SECONDARY AND FINAL LANDFALL INTO SOUTHERN
MOZAMBIQUE BY TAU 120. TC 12S SHOULD BRIEFLY RE-INTENSIFY WHEN OVER
THE MOZAMBIQUE CHANNEL BUT BEGIN TO WEAKEN BY TAU 96 DUE TO LIMITED
OCEAN HEAT CONTENT AN INCREASINGLY UNFAVORABLE VWS. THE AVAILABLE
NUMERICAL GUIDANCE IS IN CLOSE AGREEMENT WITH THE EXCEPTION OF THE
GFDN AND ECMWF WHICH BRING THE VORTEX POLEWARD AFTER TAU 72. THIS
TRACK FORECAST IS IN LINE WITH CONSENSUS. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 131200Z IS 28 FEET. NEXT WARNINGS AT 140300Z AND 141500Z.//
=========================================================================
WTXS31 PGTW 20120214 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 011//
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 011
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
140000Z --- NEAR 19.1S 48.7E
MOVEMENT PAST SIX HOURS - 270 DEGREES AT 15 KTS
POSITION ACCURATE TO WITHIN 030 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 19.1S 48.7E
---
FORECASTS:
12 HRS, VALID AT:
141200Z --- 19.8S 45.7E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 245 DEG/ 13 KTS
---
24 HRS, VALID AT:
150000Z --- 20.8S 43.2E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 235 DEG/ 11 KTS
---
36 HRS, VALID AT:
151200Z --- 22.1S 41.3E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 235 DEG/ 07 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
160000Z --- 22.9S 40.0E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 255 DEG/ 05 KTS
---
72 HRS, VALID AT:
170000Z --- 23.4S 37.9E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 270 DEG/ 04 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
180000Z --- 23.4S 36.1E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 275 DEG/ 05 KTS
---
120 HRS, VALID AT:
190000Z --- 23.3S 34.1E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
140300Z POSITION NEAR 19.3S 47.9E.
TROPICAL CYCLONE (TC) 12S (GIOVANNA), LOCATED APPROXIMATELY 95 NM
EAST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED WESTWARD AT 15 KNOTS
OVER THE PAST SIX HOURS. ANIMATED INFRARED (IR) SATELLITE IMAGERY
SHOWS TC 12S HAS MOVED OVER LAND AT 132200Z. THE PROMINENT EYE
FEATURE HAS BEEN LOST AS THE SYSTEM HAS TRACKED OVER MADAGASCAR FOR
THE PAST TWO HOURS. THE CURRENT POSITION IS BASED ON FIXES FROM PGTW
AND KNES. THE CURRENT INTENSITY IS BASED PREDOMINANTLY ON THE
STRUCTURAL APPEARANCE AND OBSERVED DEGRADATION OF THE SYSTEM FROM
THE PREVIOUS DVORAK INTENSITY FIXES BY JTWC AND KNES. TC 12S IS
TRACKING ALONG THE NORTHERN PERIPHERY OF A SUBTROPICAL RIDGE (STR)
AND IS FORECAST TO SHIFT TO A SOUTHWESTWARD TRACK, NEAR TAU 24, AS A
MID-LATITUDE TROUGH WEAKENS THE WESTERN HALF OF THE STR. THE
TRANSITORY TROUGH WILL MOVE TO THE EAST ALLOWING A STR OVER SOUTHERN
AFRICA TO BUILD EASTWARD, BECOMING THE DOMINANT STEERING INFLUENCE
BEYOND TAU 48. THE STR WILL CAUSE TC 12S TO TRACK WESTWARD INTO
MOZAMBIQUE. AS TC 12S CROSSES OVER MADAGASCAR, THE INTENSITY IS
EXPECTED TO RAPIDLY WEAKEN THROUGH TAU 24 DUE TO FRICTIONAL LAND
EFFECTS. AFTER RE-EMERGING IN THE MOZAMBIQUE CHANNEL, TC 12S WILL
BEGIN TO RECONSOLIDATE AND START STRENGTHENING AS THE OVERALL
ENVIRONMENT REMAINS FAVORABLE WITH SEA SURFACE TEMPERATURES NEAR 29
DEGREES CELSIUS, LOW VERTICAL WIND SHEAR, AND UPPER LEVEL OUTFLOW
SUPPORTING THE LOW LEVEL DEVELOPMENT. BETWEEN TAU 96 AND TAU 120 TC
12S IS EXPECTED TO MAKE LANDFALL IN MOZAMBIQUE, AND BEGIN
DISSIPATING. MODEL GUIDANCE IS IN VERY GOOD AGREEMENT THROUGH TAU
48, HOWEVER SPREADS CONSIDERABLY BEYOND. THIS FORECAST IS BASED ON
CONSENSUS THROUGH TAU 48, BUT PREFERS THE NGPS AND GFS SOLUTIONS
BEYOND TAU 48. NEXT WARNINGS AT 141500Z AND 150300Z.//
=========================================================================
WTXS31 PGTW 20120214 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 012//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 012
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
141200Z --- NEAR 19.3S 45.3E
MOVEMENT PAST SIX HOURS - 265 DEGREES AT 14 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 19.3S 45.3E
---
FORECASTS:
12 HRS, VALID AT:
150000Z --- 20.5S 42.9E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 235 DEG/ 10 KTS
---
24 HRS, VALID AT:
151200Z --- 21.7S 41.1E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 230 DEG/ 06 KTS
---
36 HRS, VALID AT:
160000Z --- 22.5S 40.0E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 235 DEG/ 04 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
161200Z --- 23.0S 39.2E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 235 DEG/ 03 KTS
---
72 HRS, VALID AT:
171200Z --- 23.7S 38.0E
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 205 DEG/ 03 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
181200Z --- 24.7S 37.5E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 115 DEG/ 04 KTS
---
120 HRS, VALID AT:
191200Z --- 25.3S 39.0E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
141500Z POSITION NEAR 19.6S 44.7E.
TROPICAL CYCLONE (TC) 12S (GIOVANNA), LOCATED APPROXIMATELY 100 NM
WEST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED WESTWARD AT 14 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
REVEALS THAT THE SYSTEM HAS TRACKED VERY QUICKLY OVER THE ISLAND,
WITH THE LOW LEVEL CIRCULATION CENTER (LLCC) PASSING JUST SOUTH OF
ANTANANARIVO AT APPROXIMATELY 140430Z. AS EXPECTED, THE CONVECTION
HAS STRUGGLED OVER THE RUGGED TERRAIN OF CENTRAL MADAGASCAR, AND LOW-
TO MID- LEVEL CLOUDS ARE NOW EXPOSED TO THE SOUTH OF THE LLCC. THE
MAXIMUM WIND SPEED REPORTED IN THE CAPITOL CITY WAS 32 KNOTS (10-MIN
AVERAGE) GUSTING TO 48 KNOTS. DESPITE THE DISRUPTION TO THE CENTRAL
CONVECTION, THE FAST TRANSLATION SPEED SHOULD ALLOW THE SYSTEM TO RE-
EMERGE IN THE MOZAMBIQUE CHANNEL AND QUICKLY REORGANIZE. THE CURRENT
POSITION IS BASED ON ANIMATED MULTISPECTRAL SATELLITE IMAGERY AND IS
IN LINE WITH FIXES FROM BOTH PGTW AND KNES. UPPER LEVEL ANALYSIS
INDICATES TC 12S SHOULD EMERGE OVER THE MOZAMBIQUE CHANNEL
APPROXIMATELY THREE DEGREES EQUATORWARD OF THE SUBTROPICAL RIDGE
(STR) AXIS, IN AN AREA WITH 15-20 KNOTS OF VERTICAL WIND SHEAR. THE
SSTS IN THE CHANNEL ARE CURRENTLY FAVORABLE FOR REDEVELOPMENT. TC
12S IS CURRENTLY TRACKING ALONG THE NORTHERN PERIPHERY OF A DEEP
LAYER STR TO THE EAST. WITH THE EXCEPTION OF THE NOGAPS MODEL, THE
REST OF THE NUMERICAL MODEL GUIDANCE IS NOW INDICATING A SHIFT IN
THE FORECAST TRACK. THE ECMWF, GFS, AND GFDN MODELS NOW DEPICT THE
SYSTEM TRACKING TOWARDS A WEAKNESS IN THE STR AS A TROUGH MOVES
THROUGH. THE STEERING RIDGE IS FORECAST TO INTENSIFY AND CONTINUE
TRACKING TC 12S AROUND ITS WESTERN PERIPHERY, RESULTING IN A CURVE
TO THE SOUTHEAST AROUND TAU 96. PREVIOUSLY, THE MODEL GUIDANCE
CALLED FOR A STR OVER AFRICA TO TAKEOVER STEERING, CAUSING THE
SYSTEM TO MAKE LANDFALL OVER MOZAMBIQUE. THE FORECAST TRACK IS
SLIGHTLY FASTER THAN CONSENSUS, GIVING WEIGHT TO THE ECMWF MODEL
WHICH HAS BEEN FORECASTING THIS MOTION FOR THE LAST THREE CYCLES.
NEXT WARNINGS AT 150300Z AND 151500Z. REFER TO TROPICAL CYCLONE 13S
(THIRTEEN) WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.
=========================================================================
WTXS31 PGTW 20120215 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 013//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 013
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
150000Z --- NEAR 20.5S 42.9E
MOVEMENT PAST SIX HOURS - 240 DEGREES AT 13 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
REPEAT POSIT: 20.5S 42.9E
---
FORECASTS:
12 HRS, VALID AT:
151200Z --- 21.8S 41.1E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 235 DEG/ 07 KTS
---
24 HRS, VALID AT:
160000Z --- 22.6S 39.9E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 240 DEG/ 05 KTS
---
36 HRS, VALID AT:
161200Z --- 23.1S 39.0E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 245 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
170000Z --- 23.6S 37.8E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 245 DEG/ 03 KTS
---
72 HRS, VALID AT:
180000Z --- 24.1S 36.6E
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 215 DEG/ 02 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
190000Z --- 24.7S 36.1E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 140 DEG/ 02 KTS
---
120 HRS, VALID AT:
200000Z --- 25.4S 36.7E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
150300Z POSITION NEAR 20.8S 42.4E.
TROPICAL CYCLONE (TC) 12S (GIOVANNA), LOCATED APPROXIMATELY 250 NM
WEST-SOUTHWEST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED WEST-
SOUTHWESTWARD AT 13 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED
SATELLITE IMAGERY SHOWS THE LOW LEVEL CIRCULATION CENTER (LLCC) HAS
MOVED BACK OVER WATER INTO THE MOZAMBIQUE CHANNEL, AND HAS
RECONSOLIDATED QUICKLY WITH DEEP CENTRAL CONVECTION RAPIDLY BUILDING
OVER THE LLCC. THE CURRENT POSITION IS BASED ON ANIMATED INFRARED
SATELLITE IMAGERY. UPPER LEVEL ANALYSIS INDICATES TC 12S REMAINS
EQUATORWARD OF A SUBTROPICAL RIDGE (STR) AXIS, WITH MODERATE
VERTICAL WIND SHEAR (VWS) (15-20 KNOTS) AND GOOD RADIAL EQUATORWARD
OUTFLOW. SEA SURFACE TEMPERATURES (SST) IN THE MOZAMBIQUE CHANNEL
ARE VERY FAVORABLE FOR REDEVELOPMENT, RANGING FROM 29 TO 31 DEGREES
CELSIUS NEAR THE WESTERN COAST OF MADAGASCAR, AND REMAIN ABOVE 28
DEGREES CELSIUS NORTH OF 24 DEGREES SOUTH. INTENSITY IS EXPECTED TO
INCREASE AS TC 12S REMAINS IN FAVORABLE SSTS AND MOVES TOWARDS THE
UPPER LEVEL STR AXIS THROUGH TAU 72. IN THE EXTENDED TAUS DECREASING
SSTS AND INCREASING VWS WILL SLOWLY WEAKEN TC GIOVANNA. TC 12S IS
TRACKING ALONG THE NORTHWESTERN PERIPHERY OF A DEEP LAYER STR,
LOCATED TO THE SOUTHEAST, BUT WILL SHIFT TO A SOUTHEASTERN TRACK AS
A MID-LATITUDE TROUGH WEAKENS THE WESTERN PERIPHERY OF THE STR
CREATING A BREAK IN THE STEERING RIDGE. THIS WEAKNESS WILL ALLOW TC
12S TO MOVE SOUTH OF THE STR AXIS, AND START TRACKING ALONG THE
SOUTHWESTERN QUADRANT. MODEL GUIDANCE HAS CONTINUED TO HAVE
DIFFICULTY WITH THE SYSTEMS TRACK IN LATER TAUS (72 TO 120), WITH
SEVERAL AIDS SHIFTING BACK TO A MORE WESTWARD TRACK FROM THE 141200Z
FORECAST. NPGS, GFDN, WBAR AND EGRR HAVE SHIFTED BACK TO A WESTWARD
TRACK INTO MOZAMBIQUE. THIS FORECAST PREFERS THE GFS AND ECMF
SOLUTION WITH A SLOWING AROUND TAU 72, WITH A SOUTHEASTERN HOOK
BETWEEN TAU 96 AND 120. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 150000Z
IS 14 FEET. NEXT WARNINGS AT 151500Z AND 160300Z. REFER TO TROPICAL
CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY
UPDATES.//
=========================================================================
WTXS31 PGTW 20120215 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 014//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 014
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
151200Z --- NEAR 23.4S 41.5E
MOVEMENT PAST SIX HOURS - 215 DEGREES AT 12 KTS
POSITION ACCURATE TO WITHIN 025 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
REPEAT POSIT: 23.4S 41.5E
---
FORECASTS:
12 HRS, VALID AT:
160000Z --- 24.4S 40.7E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 230 DEG/ 03 KTS
---
24 HRS, VALID AT:
161200Z --- 24.8S 40.2E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 250 DEG/ 03 KTS
---
36 HRS, VALID AT:
170000Z --- 25.0S 39.6E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 260 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
171200Z --- 25.1S 39.0E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 270 DEG/ 01 KTS
---
72 HRS, VALID AT:
181200Z --- 25.1S 38.4E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 280 DEG/ 02 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
191200Z --- 25.0S 37.7E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 260 DEG/ 02 KTS
---
120 HRS, VALID AT:
201200Z --- 25.1S 37.0E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
151500Z POSITION NEAR 23.7S 41.3E.
TROPICAL CYCLONE (TC) 12S (GIOVANNA), LOCATED APPROXIMATELY 405 NM
SOUTHWEST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED SOUTHWESTWARD AT
12 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) REVEALS THE LOW LEVEL CIRCULATION CENTER (LLCC) BECAME
DISPLACED FROM THE DEEP CONVECTION WHILE CROSSING MADAGASCAR DUE TO
THE LEE-SIDE JUMP PHENOMENON. THE LLCC IS NOW PARTIALLY EXPOSED,
WITH THE DEEPEST CONVECTION BUILDING ALONG THE NORTHERN SEMICIRCLE.
NOW THAT TC 12S IS TRACKING OVER THE OPEN WATER OF THE MOZAMBIQUE
CHANNEL, THE TIGHTLY CURVED SPIRAL BANDING IS CONSOLIDATING AND THE
SYSTEM IS REGENERATING. A 150626Z AMSU-B LOW LEVEL COLOR COMPOSITE
SUPPORTS THIS ASSESSMENT. THE CURRENT POSITION IS BASED ON THE
EXPOSED LLCC IN THE MSI WITH EXCELLENT CONFIDENCE. UPPER LEVEL
ANALYSIS INDICATES TC 12S IS NOW APPROXIMATELY TWO DEGREES
EQUATORWARD OF THE SUBTROPICAL RIDGE (STR) AXIS, WITH FAVORABLY LOW
VERTICAL WIND SHEAR (VWS), WHICH SHOULD PERSIST FOR THE NEXT SEVERAL
DAYS. ADDITIONALLY, TC 12S IS BENEFITTING FROM VIGOROUS EQUATORWARD
OUTFLOW OVER THE AFRICAN CONTINENT AS WELL AS AN IMPROVING POLEWARD
CHANNEL. SEA SURFACE TEMPERATURES ARE A FAVORABLE 29-30 DEGREES
CELSIUS. GIVEN THE ENVIRONMENTAL CONDITIONS, THE INTENSITY IS
EXPECTED TO STEADILY INCREASE OVER THE NEXT 72 HOURS TO A PEAK OF 65
KNOTS, AFTER WHICH VWS VALUES SHOULD CAUSE THE SYSTEM TO SLOWLY
WEAKEN. TC 12S IS CURRENTLY TRACKING ALONG THE WESTERN PERIPHERY OF
A DEEP LAYER STR LOCATED TO THE EAST. THERE IS CONSIDERABLE
DISAGREEMENT IN THE NUMERICAL MODEL GUIDANCE, WITH NO CLEAR
GROUPINGS. THIS MAY BE IN PART TO THE LEE-SIDE JUMP AND POOR
PLACEMENT OF THE LLCC WITHIN THE MODEL INITIALIZATIONS. THE OTHER
FACTOR IS DEPTH AT WHICH TC 12S WILL BE STEERED. THE MODELS WHICH
BUILD THE SYSTEM TO 60-65 KNOTS FOLLOW THE DEEP LAYER STEERING,
WHICH WOULD CONTINUE THE SOUTHWESTWARD MOTION ALONG A WEAKNESS IN
THE STR, UNTIL FINALLY TURNING THE SYSTEM BACK TO THE SOUTHEAST
AROUND TAU 96. MODELS THAT INDICATE WEAK DEVELOPMENT ARE TRACKING
MORE WESTWARD OR EVEN EQUATORWARD. GIVEN THE FAVORABLE ENVIRONMENTAL
CONDITIONS NOTED AND THE PERSISTENCE OF THE ECMWF MODEL OVER SEVERAL
DAYS TO INDICATE A SOUTHEASTWARD TURN, THE FORECAST IS BIASED
TOWARDS THAT SOLUTION VERSUS THE CONSENSUS, WHICH INDICATES
EQUATORWARD MOTION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 151200Z IS 15
FEET. NEXT WARNINGS AT 160300Z AND 161500Z. REFER TO TROPICAL
CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY
UPDATES.//
=========================================================================
WTXS31 PGTW 20120216 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 015//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 015
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
160000Z --- NEAR 24.4S 40.8E
MOVEMENT PAST SIX HOURS - 210 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
REPEAT POSIT: 24.4S 40.8E
---
FORECASTS:
12 HRS, VALID AT:
161200Z --- 24.7S 40.6E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 250 DEG/ 01 KTS
---
24 HRS, VALID AT:
170000Z --- 24.8S 40.3E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 270 DEG/ 03 KTS
---
36 HRS, VALID AT:
171200Z --- 24.8S 39.7E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 280 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
180000Z --- 24.7S 39.0E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 295 DEG/ 02 KTS
---
72 HRS, VALID AT:
190000Z --- 24.4S 38.3E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 310 DEG/ 02 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
200000Z --- 24.0S 37.8E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 310 DEG/ 03 KTS
---
120 HRS, VALID AT:
210000Z --- 23.3S 36.9E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
160300Z POSITION NEAR 24.5S 40.7E.
TROPICAL CYCLONE 12S (GIOVANNA), LOCATED APPROXIMATELY 450 NM EAST
OF MAPUTO, MOZAMBIQUE, HAD TRACKED SOUTH-SOUTHWESTWARD AT 04 KNOTS
OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY SHOWS
THE SYSTEM HAS MAINTAINED CENTRAL CONVECTION AS IT SLOWED ON ITS
FORWARD MOTION IN RESPONSE TO AN APPROACHING MID-LATITUDE TROUGH
FROM THE SOUTHWEST. THE INITIAL POSITION WAS BASED ON THE ABOVE
ANIMATION WITH POOR CONFIDENCE AND THE INITIAL INTENSITY WAS BASED
ON DVORAK ESTIMATES FROM PGTW AND KNES. UPPER LEVEL ANALYSIS
INDICATES THE SYSTEM IS APPROACHING A BREAK IN THE RIDGE IN AN AREA
OF LOW (05-10 KNOT) VERTICAL WIND SHEAR. TC 12S IS TRACKING ALONG
THE WESTERN PERIPHERY OF A DEEP-LAYERED SUBTROPICAL RIDGE (STR) TO
THE EAST. IT IS EXPECTED TO TRACK VERY SLOWLY WESTWARD AFTER TAU 24
AND LINGER IN THE COL BEFORE A SECONDARY STR, CURRENTLY ANCHORED
OVER NORTHERN SOUTH AFRICA, EXTENDS EASTWARD AND ASSUMES STEERING
TOWARD THE LATER TAUS. THIS WILL CAUSE AN EVENTUAL WEST-NORTHWEST-
WARD PROJECTION OF THE STORM MOTION. THE SYSTEM WILL SLIGHTLY
INTENSIFY OVER THE NEXT 24 HOURS AS VWS REMAINS LOW. BEYOND TAU 24,
IT WILL GRADUALLY WEAKEN DUE TO INCREASING VWS. THE MAJORITY OF THE
AVAILABLE NUMERICAL GUIDANCE RESEMBLES THIS TRACK FORECAST. ON THE
OTHER HAND, GFS DEPICTS AN EASTWARD RETROGRADATION OF THE TRACK AND
ECMWF PREDICTS AN EARLY RECURVATURE INTO THE WESTERLIES. THIS TRACK
FORECAST IS JUST TO THE LEFT OF BUT MUCH SLOWER THAN CONSENSUS.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 160000Z IS 18 FEET. NEXT WARNINGS
AT 161500Z AND 170300Z. REFER TO TROPICAL CYCLONE 13S (THIRTEEN)
WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.//
=========================================================================
WTXS31 PGTW 20120216 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 016//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 016
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
161200Z --- NEAR 24.9S 41.6E
MOVEMENT PAST SIX HOURS - 120 DEGREES AT 08 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
REPEAT POSIT: 24.9S 41.6E
---
FORECASTS:
12 HRS, VALID AT:
170000Z --- 25.4S 42.4E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 120 DEG/ 03 KTS
---
24 HRS, VALID AT:
171200Z --- 25.7S 43.0E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 090 DEG/ 02 KTS
---
36 HRS, VALID AT:
180000Z --- 25.7S 43.5E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 065 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
181200Z --- 25.2S 44.6E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 72 HR POSIT: 065 DEG/ 01 KTS
---
72 HRS, VALID AT:
191200Z --- 25.0S 45.1E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
161500Z POSITION NEAR 25.0S 41.8E.
TROPICAL CYCLONE (TC) 12S ()GIOVANNA), LOCATED APPROXIMATELY 450 NM
SOUTHWEST OF ANTANANARIVO, MADAGASCAR, HAD TRACKED AND RECURVED EAST-
SOUTHEASTWARD AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY SHOWS THE LOW LEVEL CIRCULATION
CENTER HAS BECOME PARTIALLY EXPOSED AS THE MAIN CONVECTION DECOUPLED
TO THE SOUTHEAST. WATER VAPOR SATELLITE IMAGERY OUTLINES A MID-
LATITUDE TROUGH DIGGING IN DEEP INTO THE MOZAMBIQUE CHANNEL. THIS
DEVELOPMENT HAS TRIGGERED THE RECURVATURE OF TC 12S. THE INITIAL
POSITION WAS BASED ON A 161136Z AMSU-B MICROWAVE IMAGE WITH GOOD
CONFIDENCE. THE INITIAL INTENSITY WAS BASED ON CONGRUENT DVORAK
ESTIMATES FROM PGTW, KNES, AND FMEE. UPPER LEVEL ANALYSIS INDICATES
THE CYCLONE HAS SHIFTED INTO THE POLEWARD SIDE OF THE RIDGE IN A
ZONE OF MODERATE (15-20 KNOT) VERTICAL WIND SHEAR (VWS), ALBEIT WITH
INCREASED SPEED DIVERGENCE RESULTING IN IMPROVED POLEWARD OUTFLOW.
TC 12S HAS ROUNDED THE WESTERN EDGE OF THE SUBTROPICAL RIDGE TO THE
EAST AND IS EXPECTED TO EVENTUALLY TURN INLAND INTO MADAGASCAR IN
RESPONSE TO THE AFOREMENTIONED MID-LATITUDE TROUGH. THE INCREASED
VWS, DESPITE THE IMPROVED OUTFLOW, WILL PROGRESSIVELY ERODE AND
WEAKEN THE SYSTEM. THE HIGH VWS, COUPLED WITH TOPOGRAPHIC EFFECTS,
WILL ULTIMATELY DISSIPATE THE CYCLONE INLAND BY END OF FORECAST. THE
AVAILABLE NUMERICAL GUIDANCE ARE WIDELY SPLIT WITH THE MAJORITY OF
THE MODELS DEPICTING A COUNTER-CLOCKWISE LOOP OR RETROGRADATION BACK
INTO THE MOZAMBIQUE CHANNEL. GFS, WBAR, AND ECMWF CONTINUE WITH A
RECURVATURE IN VARYING DEGREES. THIS TRACK FORECAST IS BIASED TOWARD
THE LATTER SOLUTION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 161200Z IS
13 FEET. NEXT WARNINGS AT 170300Z AND 171500Z. REFER TO TROPICAL
CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY
UPDATES.//
=========================================================================
WTXS31 PGTW 20120217 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 017//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 017
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
170000Z --- NEAR 25.5S 42.6E
MOVEMENT PAST SIX HOURS - 115 DEGREES AT 05 KTS
POSITION ACCURATE TO WITHIN 050 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
REPEAT POSIT: 25.5S 42.6E
---
FORECASTS:
12 HRS, VALID AT:
171200Z --- 25.7S 42.9E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 090 DEG/ 02 KTS
---
24 HRS, VALID AT:
180000Z --- 25.7S 43.3E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 090 DEG/ 02 KTS
---
36 HRS, VALID AT:
181200Z --- 25.7S 43.7E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 075 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
190000Z --- 25.5S 44.4E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 065 DEG/ 04 KTS
---
72 HRS, VALID AT:
200000Z --- 24.9S 45.9E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
170300Z POSITION NEAR 25.6S 42.7E.
TROPICAL CYCLONE 12S (GIOVANNA), LOCATED APPROXIMATELY 465 NM SOUTH-
SOUTHWEST OF ANTANANARIVO, MADAGASCAR, HAD TRACKED EAST-
SOUTHEASTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED
SATELLITE IMAGERY INDICATES THAT THE SYSTEM HAS WEAKENED SLIGHTLY
OVER THE PAST 12 HOURS WITH SIGNIFICANT WARMING OF CONVECTIVE CLOUD
TOPS AND FRAGMENTED CONVECTIVE BANDING. A 162254Z AMSU IMAGE DEPICTS
A WELL-DEFINED BUT BROAD LOW-LEVEL CIRCULATION CENTER (LLCC) WITH
DEEP CONVECTION CONFINED TO THE SOUTH SEMI-CIRCLE. A 161832Z ASCAT
IMAGE SHOWED 40-45 KNOT WINDS OVER THE SOUTH SEMI-CIRCLE. THERE IS
FAIR CONFIDENCE IN THE CURRENT POSITION DUE TO THE BROAD BUT DEFINED
NATURE OF THE LLCC. THE CURRENT INTENSITY IS HEDGED A LITTLE HIGHER
THAN THE ASCAT HAD INDICATED BASED ON AN AVERAGE OF DVORAK CURRENT
INTENSITY ESTIMATES RANGING FROM 45 TO 55 KNOTS. TC 12S IS TRACKING
SLOWLY ALONG THE SOUTHWEST PERIPHERY OF A WEAK EXTENSION OF THE
SUBTROPICAL RIDGE, BUILT OVER NORTHERN MADAGASCAR, AND IS EXPECTED
TO CONTINUE TRACKING EASTWARD THROUGH THE FORECAST PERIOD. DYNAMIC
MODEL GUIDANCE, WHICH HAD BEEN IN VERY POOR AGREEMENT, HAS NOW
SHIFTED TO AN EASTWARD TRACK AND, WITH THE EXCEPTION OF GFDN, IS IN
FAIR AGREEMENT. THE JTWC FORECAST FAVORS THE ECMWF TRACKER, WHICH
HAS EXCELLED THUS FAR AND IS POSITIONED CLOSE TO THE MODEL CONSENSUS
AS WELL. TC 12S IS FORECAST TO INTENSIFY SLIGHTLY BUT UPPER-LEVEL
CONVERGENCE ASSOCIATED WITH A DEEP SHORT-WAVE TROUGH MAY HAMPER ANY
DEVELOPMENT. ADDITIONALLY, LAND INTERACTION WILL SOON HINDER
DEVELOPMENT AND EVENTUALLY LEAD TO DISSIPATION BY TAU 72. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 170000Z IS 15 FEET. NEXT WARNINGS AT
171500Z AND 180300Z. REFER TO TROPICAL CYCLONE 13S (THIRTEEN)
WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.//
=========================================================================
WTXS31 PGTW 20120217 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 018//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 018
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
171200Z --- NEAR 25.8S 43.1E
MOVEMENT PAST SIX HOURS - 120 DEGREES AT 02 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
REPEAT POSIT: 25.8S 43.1E
---
FORECASTS:
12 HRS, VALID AT:
180000Z --- 25.9S 43.5E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 085 DEG/ 05 KTS
---
24 HRS, VALID AT:
181200Z --- 25.8S 44.5E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 065 DEG/ 06 KTS
---
36 HRS, VALID AT:
190000Z --- 25.3S 45.6E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 48 HR POSIT: 055 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
191200Z --- 24.6S 46.7E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
171500Z POSITION NEAR 25.8S 43.2E.
TROPICAL CYCLONE 12S (GIOVANNA), LOCATED APPROXIMATELY 445 NM SOUTH-
SOUTHWEST OF ANTANANARIVO, MADAGASCAR, HAD TRACKED EAST-
SOUTHEASTWARD AT 02 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY DEPICTS A WELL-DEFINED LOW-LEVEL
CIRCULATION CENTER (LLCC) WITH BUILDING CONVECTION SPIRALING INWARDS
AROUND THE EASTERN AND SOUTHERN QUADRANTS. A 171125Z AMSU-B 89 GHZ
IMAGE DEPICTS THE DEEP CONVECTION WRAPPING INTO THE SOUTHWESTERN
PORTION OF THE LLCC. THE CURRENT POSITION IS BASED ON THE AMSU-B
IMAGE WITH GOOD CONFIDENCE. THE CURRENT INTENSITY IS BASED ON THE
HIGHER SIDE OF DVORAK ESTIMATES RANGING FROM 45-55 KNOTS FROM
KNES/FMEE AND PGTW RESPECTIVELY, DUE TO THE CURRENT CONVECTIVE
SIGNATURE IN MICROWAVE DATA. UPPER-LEVEL ANALYSIS INDICATES THE
SYSTEM IS JUST TO THE SOUTHEAST OF A POINT-SOURCE OF DIFFLUENCE
UNDER WEAK (05-10 KNOT) WESTERLY VERTICAL WIND SHEAR (VWS). HOWEVER,
SPEED DIVERGENCE IS ENHANCED DOWNSTREAM OF THE LLCC DUE TO A
POLEWARD TAP INTO THE MID-LATITUDE WESTERLIES. ANIMATED WATER VAPOR
IMAGERY CLEARLY SHOWS THE CIRRUS BLOW-OFF QUICKLY STREAMING
POLEWARD. ADDITIONALLY, THE STR CAN BE SEEN BUILDING OUT OVER
SOUTHERN AFRICA. TC 12S IS CURRENTLY TRACKING SLOWLY ALONG THE
SOUTHWEST PERIPHERY OF A WEAK EXTENSION OF THE SUBTROPICAL RIDGE,
BUILT OVER NORTHERN MADAGASCAR. BY TAU 24, THE SYSTEM SHOULD COME
UNDER THE INFLUENCE OF THE SOUTHEASTERN PERIPHERY OF THE STR OVER
SOUTHERN AFRICA CAUSING IT TO TRACK OVER SOUTHERN MADAGASCAR BY TAU
48. TC 12S SHOULD DISSIPATE OVERLAND BY TAU 72 DUE TO LAND
INTERACTION. NUMERICAL MODEL GUIDANCE CONTINUES TO COLLECTIVELY SHOW
A GENERALLY EASTWARDS TRACK BUT SUCCESSIVE MODEL RUNS ARE HINTING
TOWARDS THE LLCC TRACKING SOUTH OF MADAGASCAR AND DISSIPATING
FURTHER OUT OVER THE SOUTHWESTERN INDIAN OCEAN. THE OFFICIAL
FORECAST FAVORS THE ECMWF, WHICH IS THE LEFT MOST OBJECTIVE AID AND
TAKES THE LLCC OVER SOUTHERN MADAGASCAR DUE TO THE EXPECTED
INFLUENCE OF THE STR TO THE WEST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
171200Z IS 15 FEET. NEXT WARNINGS AT 180300Z AND 181500Z.
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
FOR TWELVE-HOURLY UPDATES.//
=========================================================================
WTXS31 PGTW 20120218 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 019//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 019
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
180000Z --- NEAR 26.4S 43.1E
MOVEMENT PAST SIX HOURS - 140 DEGREES AT 03 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
REPEAT POSIT: 26.4S 43.1E
---
FORECASTS:
12 HRS, VALID AT:
181200Z --- 26.5S 44.5E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 085 DEG/ 09 KTS
---
24 HRS, VALID AT:
190000Z --- 26.3S 46.6E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 085 DEG/ 09 KTS
---
36 HRS, VALID AT:
191200Z --- 26.2S 48.6E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 48 HR POSIT: 080 DEG/ 08 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
200000Z --- 25.9S 50.4E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
180300Z POSITION NEAR 26.4S 43.5E.
TROPICAL CYCLONE 12S (GIOVANNA), LOCATED APPROXIMATELY 495 NM SOUTH-
SOUTHWEST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED SOUTHEASTWARD AT
03 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE
IMAGERY SHOWS A WELL DEFINED LOW LEVEL CIRCULATION CENTER (LLCC)
WITH GOOD POLEWARD OUTFLOW SUPPORTING THE CURRENT 55 KNOT INTENSITY.
OVER THE PAST 12 HOURS, TC 12S HAD SEEN A BRIEF PERIOD OF WEAKENING,
HOWEVER IN THE LAST SIX HOURS IMPROVING LOW LEVEL INFLOW AND
ENHANCED POLEWARD OUTFLOW HAS LED TO A BRIEF INTENSIFICATION OF THE
LLCC. TC 12S HAS BEEN TRACKING SLOWLY OVER THE PAST 12 HOURS AS THE
COMPETING STEERING INFLUENCES FROM THE SUBTROPICAL RIDGE (STR)
LOCATED OVER SOUTHERN AFRICA AND THE STR LOCATED OVER MADAGASCAR
HAVE REMAINED EQUALLY INFLUENTIAL. UPPER LEVEL ANALYSIS SHOWS THE
STRONG POLEWARD OUTFLOW PRESENT OVER THE PAST 48 HOURS IS BEGINNING
TO BE IMPINGED BY A WESTERLY JET OUT OF SOUTH AFRICA, AND WILL
FURTHER WEAKEN THE SYSTEM AS VERTICAL WIND SHEAR (VWS) INCREASES. TC
12S IS EXPECTED TO MAINTAIN A GENERALLY EASTWARD TRACK AS BOTH STRS
INTERACT, WITH THE STR OVER MADAGASCAR BEING SLIGHTLY MORE DOMINANT.
INTENSITY WILL DECREASE BASED ON MARGINAL LOW LEVEL SUPPORT AND
INCREASING VWS HAMPERING UPPER LEVEL OUTFLOW. MODEL AND INTENSITY
GUIDANCE ARE IN FAIR AGREEMENT WITH THIS FORECAST. THE OUTLIERS ARE
NGPS AND WBAR SHOWING TC 12S TRACKING INTO THE MID-LATITUDE FLOW
VICE A RECURVATURE TO THE NORTH AS DEPICTED BY EGRR, GFS, AND ECMF.
THIS FORECAST DISSIPATES TC 12S BY TAU 48, AND FAVORS THE GFS AND
ECMF SOLUTION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 180000Z IS 15
FEET. NEXT WARNINGS AT 181500Z AND 190300Z. REFER TO TROPICAL
CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY
UPDATES.//
=========================================================================
WTXS31 PGTW 20120218 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 020//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 020
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
181200Z --- NEAR 26.5S 44.6E
MOVEMENT PAST SIX HOURS - 095 DEGREES AT 09 KTS
POSITION ACCURATE TO WITHIN 030 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
REPEAT POSIT: 26.5S 44.6E
---
FORECASTS:
12 HRS, VALID AT:
190000Z --- 26.2S 46.6E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 075 DEG/ 10 KTS
---
24 HRS, VALID AT:
191200Z --- 25.7S 48.8E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 080 DEG/ 08 KTS
---
36 HRS, VALID AT:
200000Z --- 25.4S 50.5E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 070 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
201200Z --- 25.2S 51.1E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 025 DEG/ 02 KTS
---
72 HRS, VALID AT:
211200Z --- 24.5S 51.5E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 96 HR POSIT: 350 DEG/ 03 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
221200Z --- 23.3S 51.3E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
181500Z POSITION NEAR 26.4S 45.1E.
TROPICAL CYCLONE 12S (GIOVANNA), LOCATED APPROXIMATELY 475 NM SOUTH-
SOUTHWEST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED EASTWARD AT 09
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) REVEALS THAT TC 12S SHOWED SIGNS OF STRENGTHENING,
WITH A WELL DEVELOPED EYE; HOWEVER THE EYEWALL IS NOW WEAKENING AND
BECOMING OBSCURED BY CONVECTION ON THE POLEWARD SIDE OF THE LOW
LEVEL CIRCULATION CENTER (LLCC). THE CURRENT POSITION IS BASED ON
THE MSI AND AN 181114Z AMSU-B MICROWAVE SATELLITE IMAGE, AND IS IN
AGREEMENT WITH THE PGTW AND KNES FIXES. THE CURRENT INTENSITY IS
BASED ON THE INTENSIFICATION NOTED AND DVORAK ESTIMATES OF 65 KNOTS
FROM PGTW AND FMEE. UPPER LEVEL ANALYSIS INDICATES TC 12S IS JUST
SOUTH OF THE SUBTROPICAL RIDGE (STR) AXIS IN A REGION OF LOW
VERTICAL WIND SHEAR (VWS). ANIMATED SATELLITE WATER VAPOR IMAGERY
SHOWS THE SYSTEM HAS EXCELLENT POLEWARD OUTFLOW. ALTHOUGH A JET OVER
SOUTH AFRICA CAN BE DISCERNED, THIS FLOW IS SOUTH OF TC 12S, AND
IMPACTS OF THIS FEATURE ON THE VWS APPEAR TO BE MINIMAL. THE MAIN
IMPEDIMENT TO DEVELOPMENT IN THE SHORT TERM IS CONTINUED INTERACTION
WITH THE ISLAND OF MADAGASCAR TO THE NORTH. IN THE LONG TERM, THE
VWS WILL INCREASE AS TC 13S APPROACHES FROM THE NORTHEAST. TC 12S IS
CURRENTLY TRACKING ALONG THE SOUTHERN PERIPHERY OF THE STR LOCATED
OVER SOUTH AFRICA. THE SYSTEM IS FORECAST TO WEAKEN VERY GRADUALLY,
AND SHOULD MAKE A CURVE TO THE NORTH AFTER TAU 48. THERE IS A SPLIT
IN THE NUMERICAL MODELS WITH NOGAPS AND WBAR SUGGESTING A MORE
EASTWARD RUNNING TRACK UNDER THE INFLUENCE OF A STRONG ANTICYCLONE
TO THE EAST; HOWEVER THIS SOLUTION DOES NOT APPEAR TO TAKE INTO
ACCOUNT THE EXPECTED WEAKENING OF THIS ANTICYCLONE BY TC 13S. THE
FORECAST TRACK FAVORS THE MODELS WHICH CONTINUE TO STEER THE SYSTEM
AROUND THE ANTICYCLONE TO THE WEST, WITH DISSIPATION AROUND TAU 96.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 181200Z IS 15 FEET. NEXT WARNINGS
AT 190300Z AND 191500Z. REFER TO TROPICAL CYCLONE 13S (THIRTEEN)
WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.//
=========================================================================
WTXS31 PGTW 20120219 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 021//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 021
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
190000Z --- NEAR 26.1S 47.1E
MOVEMENT PAST SIX HOURS - 070 DEGREES AT 12 KTS
POSITION ACCURATE TO WITHIN 030 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
REPEAT POSIT: 26.1S 47.1E
---
FORECASTS:
12 HRS, VALID AT:
191200Z --- 25.5S 49.4E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 070 DEG/ 06 KTS
---
24 HRS, VALID AT:
200000Z --- 25.1S 50.6E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 065 DEG/ 06 KTS
---
36 HRS, VALID AT:
201200Z --- 24.6S 51.7E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 010 DEG/ 05 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
210000Z --- 23.7S 51.9E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 360 DEG/ 03 KTS
---
72 HRS, VALID AT:
220000Z --- 22.6S 51.9E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
190300Z POSITION NEAR 25.9S 47.7E.
TROPICAL CYCLONE 12S (GIOVANNA), LOCATED APPROXIMATELY 430 NM SOUTH
OF ANTANANARIVO, MADAGASCAR, HAS TRACKED EAST-NORTHEASTWARD AT 12
KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY
SHOWS DEEP CONVECTION HAS PERSISTED WITH THE SUPPORT OF A STRONG
POLEWARD OUTFLOW CHANNEL. THE EYE FEATURE HAS BROKEN DOWN OVER THE
PAST 12 HOURS, HOWEVER DVORAK ESTIMATES FROM PGTW AND KNES CONTINUE
TO SHOW AN INTENSE SYSTEM. TC 12S HAS SPED UP OVER THE PAST 12 HOURS
AND IS BEGINNING TO TURN SLIGHTLY NORTHWARD IN THAT LAST SIX HOURS.
UPPER LEVEL ANALYSIS INDICATES TC 12S REMAINS IN LOW TO MODERATE
VERTICAL WIND SHEAR (VWS) (10-15 KNOTS). THE MAIN IMPEDIMENT TO
DEVELOPMENT IN THE SHORT TERM IS CONTINUED INTERACTION WITH THE
ISLAND OF MADAGASCAR TO THE NORTH. IN THE LONG TERM, THE VWS WILL
INCREASE AS TC 13S APPROACHES FROM THE NORTHEAST. TC 12S IS
CURRENTLY TRACKING ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL
RIDGE (STR) LOCATED OVER SOUTH AFRICA. THE SYSTEM IS FORECAST TO
WEAKEN GRADUALLY, AND SHOULD MAKE A CURVE TO THE NORTH AFTER TAU 36.
NUMERICAL GUIDANCE HAS SPLIT RECENTLY WITH NGPS, GFS, WBAR, AND GFDN
SHOWING A TURN TO THE SOUTHEAST. ECMF AND EGRR REMAIN WITH A TURN
NORTHWARD. THIS FORECAST PREFERS THE ECMF SOLUTION, HOWEVER THERE IS
SOME CONCERN REGARDING THIS FORECAST AS TC 13S HAS NOT DEVELOPED AS
STRONGLY AS MODEL GUIDANCE SUGGESTS. THIS COULD PROVIDE AN ALTERNATE
SCENARIO WHERE TC 12S BEGINS TRACKING ALONG THE STR LOCATED TO THE
EAST DUE TO THE LACK OF MODIFICATION BY TC 13S AS EXPECTED. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 190000Z IS 15 FEET. NEXT WARNINGS AT
191500Z AND 200300Z. REFER TO TROPICAL CYCLONE 13S (THIRTEEN)
WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.//
=========================================================================
WTXS31 PGTW 20120219 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 022//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 022
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
191200Z --- NEAR 26.0S 50.5E
MOVEMENT PAST SIX HOURS - 095 DEGREES AT 14 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
REPEAT POSIT: 26.0S 50.5E
---
FORECASTS:
12 HRS, VALID AT:
200000Z --- 26.0S 52.4E
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
135 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 090 DEG/ 04 KTS
---
24 HRS, VALID AT:
201200Z --- 26.0S 53.4E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
135 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 105 DEG/ 04 KTS
---
36 HRS, VALID AT:
210000Z --- 26.2S 54.3E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
135 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 115 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
211200Z --- 26.7S 55.5E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
VECTOR TO 72 HR POSIT: 130 DEG/ 06 KTS
---
72 HRS, VALID AT:
221200Z --- 28.2S 57.7E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
191500Z POSITION NEAR 26.0S 51.0E.
TROPICAL CYCLONE 12S (GIOVANNA), LOCATED APPROXIMATELY 455 NM SOUTH-
SOUTHEAST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED EASTWARD AT 14
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS THAT TC 12S UNDERWENT ANOTHER PERIOD OF
INTENSIFICATION OVER THE PAST 12 HOURS, INCLUDING A GROWTH IN
HORIZONTAL EXTENT AND THE FORMATION OF A WELL-DEFINED EYE, WHICH HAS
RECENTLY COLLAPSED. THE CURRENT POSITION IS EXTRAPOLATED FROM A
190757 TRMM 85GHZ MICROWAVE SATELLITE IMAGE AND IS IN AGREEMENT WITH
PGTW AND KNES FIXES. THE CURRENT INTENSITY IS ASSESSED AT 85 KNOTS,
WHICH IS AN AVERAGE OF AGENCY FIXES RANGING FROM 77 TO 90 KNOTS.
UPPER LEVEL ANALYSIS INDICATES THE SYSTEM IS NOW POLEWARD OF THE
SUBTROPICAL RIDGE AXIS AND BEGINNING TO FEEL THE EFFECTS OF STRONG
VERTICAL WIND SHEAR (VWS) ASSOCIATED WITH THE MID-LATITUDE WESTERLY
FLOW. ANIMATED WATER VAPOR IMAGERY CLEARLY DEPICTS TC 12S BEING
STRETCHED TO THE SOUTHEAST IN RESPONSE TO A DEEP TROUGH APPROACHING
FROM THE WEST, WHICH IS ADDING TO THE VWS. THE SYSTEM HAD BEEN
TRACKING ALONG THE SOUTHERN PERIPHERY OF AN ANTICYCLONE TO THE WEST,
AND THE PREVIOUS FORECAST HAD CALLED FOR A NORTHWARD TURN IN THE MID-
RANGE TAUS. HOWEVER, THIS FORECAST, WHICH TRACKS THE SYSTEM EASTWARD
AND THEN TURNS INTO THE WESTERLIES, MARKS A CHANGE IN THE PREVAILING
PHILOSOPHY. TC 12S HAS MOVED RAPIDLY EASTWARD, AND THE APPROACHING
UPPER-LEVEL TROUGH SHOULD FORCE THE STORM IN A EAST-SOUTHEASTWARD
DIRECTION, AFTER WHICH AN ANTICYCLONE TO THE EAST WILL BECOME THE
DOMINANT STEERING MECHANISM. AS TC 12S TRACKS MORE POLEWARD, VWS
WILL CONTINUE TO INCREASE AND HASTEN THE DISSIPATION. IN LIEU OF
THIS FORECAST CHANGE, THE SYSTEM IS NOW EXPECTED TO BEGIN EXTRA-
TROPICAL TRANSITION (ETT) AT TAU 48, AND SHOULD COMPLETE ETT BY TAU
72, BY WHICH TIME IT WILL BE FULLY EMBEDDED WITHIN THE BAROCLINIC
ZONE. THERE IS SIGNIFICANT DISAGREEMENT AMONG THE NUMERICAL MODEL
GUIDANCE REGARDING THE FORECAST TRACK. THE ECMWF MODEL STILL CALLS
FOR A NORTHWARD TURN, BUT A REVIEW OF LIMITED MODEL FIELDS INDICATES
THE MODEL ACTUALLY DISSIPATES THE SYSTEM BY TAU 48 AND BEGINS
TRACKING ANOTHER CIRCULATION. THE GFDN AND NOGAPS MODELS INDICATE AN
INITIAL BEND EQUATORWARD FOLLOWED BY A RECURVATURE. FINALLY, GFS AND
WBAR GENERALLY AGREE ON AN EAST-SOUTHEAST TRACK AND ETT. THE
FORECAST TRACK IS BIASED TOWARDS THE GFS SOLUTION. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 191200Z IS 20 FEET. NEXT WARNINGS AT
200300Z AND 201500Z. REFER TO TROPICAL CYCLONE 13S (THIRTEEN)
WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.
=========================================================================
WTXS31 PGTW 20120220 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 023//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 023
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
200000Z --- NEAR 26.2S 53.2E
MOVEMENT PAST SIX HOURS - 095 DEGREES AT 11 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT
135 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
115 NM NORTHWEST QUADRANT
REPEAT POSIT: 26.2S 53.2E
---
FORECASTS:
12 HRS, VALID AT:
201200Z --- 26.9S 55.2E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
135 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 135 DEG/ 10 KTS
---
24 HRS, VALID AT:
210000Z --- 28.3S 56.8E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
135 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 150 DEG/ 13 KTS
---
36 HRS, VALID AT:
211200Z --- 30.5S 58.4E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
135 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 150 DEG/ 15 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
220000Z --- 33.1S 60.3E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
200300Z POSITION NEAR 26.4S 53.7E.
TROPICAL CYCLONE 12S (GIOVANNA), LOCATED APPROXIMATELY 455 NM SOUTH-
SOUTHEAST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED EASTWARD AT 14
KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED (IR) SATELLITE
IMAGERY SHOWS THE ORGANIZATION OF THE BANDING CONVECTION OVER THE
LOW LEVEL CIRCULATION CENTER (LLCC) HAS STARTED TO BREAK DOWN AS TC
12S HAS MOVED SOUTH OF AN UPPER LEVEL SUBTROPICAL RIDGE (STR) AXIS
INTO HIGH VERTICAL WIND SHEAR (VWS) (30 KNOTS PLUS). THE EQUATORWARD
OUTFLOW CHANNEL HAS BEEN RAPIDLY WEAKENING, HOWEVER THE POLEWARD
OUTFLOW CHANNEL REMAINS VERY FAVORABLE WITH SUPPORT FROM A DEEP MID-
LATITUDE TROUGH AMPLIFYING THE WESTERLY OUTFLOW GRADIENT. THE
CURRENT POSITION IS BASED ON LOOPING IR IMAGERY AND FIXES FROM PGTW
AND KNES, BUT AS CENTRAL CONVECTION HAS LOST ORGANIZATION, THERE IS
ONLY MARGINAL CONFIDENCE IN THE POSITION. THE CURRENT INTENSITY IS
BASED ON DVORAK ESTIMATES FROM PGTW AND KNES INDICATING 65 KNOTS.
TC 12S IS CURRENTLY TRACKING ALONG THE LEADING EDGE OF A DEEP MID-
LATITUDE TROUGH AND THE SOUTHWESTERN PERIPHERY OF A DEEP STR
BUILDING TOWARDS MADAGASCAR. TC 12S IS EXPECTED TO CONTINUE TRACKING
ALONG THE SOUTHWESTERN PERIPHERY OF THE STR THROUGH TAU 48.
INTENSITIES WILL RAPIDLY DECREASE AS THE MID-LATITUDE TROUGH TRACKS
EASTWARD LEADING TO INCREASED VWS. ADDITIONALLY, TC 12S WILL TRACK
OVER DECREASING SEA SURFACE TEMPERATURES, WEAKENING THE LLCC. THE
SYSTEM IS EXPECTED TO START EXTRA-TROPICAL TRANSITION BY TAU 36 AND
SHOULD BE COMPLETE BY TAU 48. MODEL GUIDANCE IS IN FAIR AGREEMENT
WITH THE SOUTHEASTERN TRACK, HOWEVER THE MAJORITY SLOW THE SYSTEM
BETWEEN TAU 12 AND 36. THIS IS LIKELY DUE TO MODELS SHOWING TC 13S
AS A MORE INTENSE SYSTEM THAN CURRENTLY FORECAST, WHICH LEADS TO A
WEAKER STEERING RIDGE ALONG THE STRS WESTERN PERIPHERY. BASED ON THE
CURRENT INTENSITIES FOR TC 13S BEING LESS THAN MODEL GUIDANCE
SUGGESTS, THE TRACK SPEED FOR TC 12S HAS BEEN KEPT HIGHER THAN
CONSENSUS INDICATES. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 200000Z IS
20 FEET. NEXT WARNINGS AT 201500Z AND 210300Z. REFER TO TROPICAL
CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY
UPDATES.//
=========================================================================
WTXS31 PGTW 20120220 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 024//
REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 024
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
201200Z --- NEAR 25.0S 53.1E
MOVEMENT PAST SIX HOURS - 335 DEGREES AT 09 KTS
POSITION ACCURATE TO WITHIN 025 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
REPEAT POSIT: 25.0S 53.1E
---
FORECASTS:
12 HRS, VALID AT:
210000Z --- 23.6S 52.6E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 24 HR POSIT: 350 DEG/ 05 KTS
---
24 HRS, VALID AT:
211200Z --- 22.7S 52.4E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
201500Z POSITION NEAR 24.7S 53.0E.
TROPICAL CYCLONE 12S (GIOVANNA), LOCATED APPROXIMATELY 490 NM
SOUTHEAST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED NORTH-
NORTHWESTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) REVEALS THAT THE LOW LEVEL
CIRCULATION CENTER (LLCC) BECAME COMPLETELY EXPOSED OVER THE PAST 12
HOURS AS THE DEEP CONVECTION WAS STRONGLY SHEARED DOWN STREAM. AS A
RESULT OF THIS DE-COUPLING THE LLCC IS NOW BEING STEERED SLOWLY
EQUATORWARD UNDER THE INFLUENCE OF A LOW- TO MID-LEVEL ANTICYCLONE
LOCATED OVER EASTERN SOUTH AFRICA. THE CURRENT POSITION IS BASED ON
THE EXPOSED LLCC IN MSI WITH EXCELLENT CONFIDENCE. THE CURRENT
INTENSITY IS ASSESSED AT 45 KNOTS BASED ON THE DVORAK ESTIMATES FROM
PGTW AND KNES. ANIMATED WATER VAPOR IMAGERY DEPICTS THE QUICK DEMISE
OF TC 12S. UPPER LEVEL ANALYSIS INDICATES THE LLCC REMAINS SOUTH OF
THE SUBTROPICAL RIDGE AXIS AND IS UNDER 30-40 KNOTS OF VERTICAL WIND
SHEAR (VWS). DUE TO THE DE-COUPLING OF THE LLCC, THE FORECAST HAS
NOW CHANGED TO A NORTH-NORTHWESTERLY TRACK, WITH CONTINUED WEAKENING
OVER THE NEXT 24 HOURS DUE TO SUSTAINED HIGH VWS AND DRIER AIR. TC
12S IS FORECAST TO BE BELOW TROPICAL STORM STRENGTH BY TAU 24. THE
MAJORITY OF THE NUMERICAL MODEL GUIDANCE TRACKS THE SYSTEM EASTWARD
UNDER THE INFLUENCE OF AN ANTICYCLONE TO THE NORTH THAT IS BEING
SPUN UP BY TC 13S. THE ECMWF AND UKMO MODELS CORRECTLY PICKED UP ON
THE LLCC SEPARATION AND SUBSEQUENT NORTHWARD MOVEMENT. THEREFORE,
THE FORECAST IS HEAVILY BIASED TOWARDS THESE MODELS VICE CONSENSUS.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 201200Z IS 18 FEET. NEXT WARNINGS
AT 210300Z. REFER TO TROPICAL CYCLONE 13S (THIRTEEN) WARNINGS
(WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.
=========================================================================
WTXS31 PGTW 20120221 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 025//
REFER TO TROPICAL CYCLONE 13S (HILWA) WARNINGS (WTXS32 PGTW)
RMKS/
1. TROPICAL CYCLONE 12S (GIOVANNA) WARNING NR 025
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
210000Z --- NEAR 23.4S 52.6E
MOVEMENT PAST SIX HOURS - 345 DEGREES AT 07 KTS
POSITION ACCURATE TO WITHIN 045 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
REPEAT POSIT: 23.4S 52.6E
---
FORECASTS:
12 HRS, VALID AT:
211200Z --- 22.1S 51.6E
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
210300Z POSITION NEAR 23.1S 52.3E.
TROPICAL CYCLONE 12S (GIOVANNA), LOCATED APPROXIMATELY 410 NM
SOUTHEAST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED NORTH-
NORTHWESTWARD AT 07 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED
(IR) SATELLITE IMAGERY DEPICTS A FULLY-EXPOSED, DEFINED LOW-LEVEL
CIRCULATION CENTER WITH ISOLATED, DEEP CONVECTION SHEARED 200NM TO
THE SOUTHEAST DUE TO STRONG (30-40 KNOTS) NORTHWESTERLY VERTICAL
WIND SHEAR. THERE IS HIGH CONFIDENCE IN THE CURRENT POSITION BASED
ON THE IR IMAGERY AND A 202327Z TRMM 37 GHZ IMAGE. THE CURRENT
INTENSITY IS BASED ON A DVORAK CURRENT INTENSITY ESTIMATE OF 30
KNOTS FROM PGTW. TC 12S IS EXPECTED TO CONTINUE WEAKENING WHILE
TRACKING SLOWLY NORTH-NORTHWESTWARD. AVAILABLE MODEL GUIDANCE
SUPPORTS THIS TRACK. THIS IS THE FINAL WARNING ON THIS SYSTEM BY THE
JOINT TYPHOON WARNING CENTER. THE SYSTEM WILL BE CLOSELY MONITORED
FOR SIGNS OF REGENERATION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
210000Z IS 12 FEET. REFER TO TROPICAL CYCLONE 13S (HILWA) WARNINGS
(WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.//
Tropical cyclone tracks developed by Michael Bath using operational warnings and advisories.
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Document: tropical_cyclone_giovanna_jtwc_advisories.htm
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