Updated: 17 June 2020
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| Tropical Cyclones
[Index] | Tropical Cyclone HELLEN : JTWC Advisories |
| Season 2013-2014 Summaries (Operational Data): [AU] [SIO] [SPAC] [SH] | |
| ---> Tropical Cyclone HELLEN Track Map and Data |
WTXS21 PGTW 20140326 20:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
225 NM EITHER SIDE OF A LINE FROM 10.6S 39.3E TO 13.9S 45.8E
WITHIN THE NEXT 06 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 25 TO 30 KNOTS. METSAT
IMAGERY AT 262130Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 10.7S 39.8E. THE SYSTEM IS MOVING EASTWARD AT 04 KNOTS.
2. REMARKS:
THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 10.9S 40.7E IS NOW
LOCATED NEAR 10.7S 39.4E, APPROXIMATELY 600 NM NORTHWEST OF
ANTANANARIVO, MADAGASCAR. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS A CONSOLIDATING LOW-LEVEL CIRCULATION CENTER (LLCC)
WITH FORMATIVE BANDING WRAPPING INTO THE LLCC. THE LLCC IS OVER LAND
STRADDLING THE TANZANIA-MOZAMBIQUE BORDER AND APPEARS TO BE SLOWLY
APPROACHING THE COAST INTO THE MOZAMBIQUE CHANNEL. UPPER-LEVEL
ANALYSIS INDICATES THE SYSTEM IS IN A FAVORABLE ENVIRONMENT WITH LOW
(5 TO 10 KNOT) VERTICAL WIND SHEAR AND ENHANCED EASTWARD AND
POLEWARD OUTFLOW CHANNELS. ADDITIONALLY, WARM SEA SURFACE
TEMPERATURES IN THE CHANNEL ARE CONDUCIVE FOR FURTHER DEVELOPMENT.
THE DYNAMIC MODELS INDICATE AN EAST-SOUTHEASTWARD TO SOUTHEASTWARD
TRACK WITH RAPID DEVELOPMENT AFTER TAU 24. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1004 MB. SEE REF A (WTXS21 PGTW 262000) FOR
FURTHER DETAILS. IN VIEW OF THE CYCLONES IMMINENT EXIT INTO WARM
WATER AND GIVEN THE FAVORABLE ENVIRONMENTAL CONDITIONS, 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
272000Z. //
=========================================================================
WTXS21 PGTW 20140327 20:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT REISSUED//
REF/A/JOINT TYPHOON WRNCEN PEARL HARBOR HI/262000Z MAR 14//
AMPN/REF IS TROPICAL CYCLONE FORMATION ALERT (WTXS21 PGTW 262000)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
215 NM EITHER SIDE OF A LINE FROM 12.1S 39.7E TO 16.0S 45.5E
WITHIN THE NEXT 06 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 25 TO 30 KNOTS. METSAT
IMAGERY AT 271930Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 12.8S 40.7E. THE SYSTEM IS MOVING SOUTH-SOUTHWESTWARD AT 05
KNOTS.
2. REMARKS:
THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 12.5S 40.8E
IS NOW LOCATED NEAR 12.8S 40.7E, APPROXIMATELY 515 NM NORTHWEST OF
ANTANANARIVO, MADAGASCAR. ANIMATED SATELLITE IMAGERY SHOWS A
STEADILY CONSOLIDATING SYSTEM WITH FORMATIVE, ALBEIT FRAGMENTED AND
SHALLOW BANDING, WRAPPING INTO A WELL-DEFINED LOW LEVEL CIRCULATION
CENTER (LLCC). THE LLCC HAS MOVED OFFSHORE BUT IS SLOWLY DRIFTING
SOUTHWARD CLOSE TO THE MOZAMBIQUE COAST. UPPER-LEVEL ANALYSIS
INDICATES THE SYSTEM REMAINS IN A FAVORABLE ENVIRONMENT WITH LOW (05
TO 10 KNOT) VERTICAL WIND SHEAR AND STRONG EASTWARD AND POLEWARD
OUTFLOW CHANNELS. ADDITIONALLY, WARM SEA SURFACE TEMPERATURES IN THE
MOZAMBIQUE CHANNEL ARE CONDUCIVE FOR FURTHER DEVELOPMENT. HOWEVER,
THE CYCLONES PROXIMITY TO THE AFRICAN LANDMASS IS LIMITING THE
INFLUX OF MOISTURE NECESSARY FOR FURTHER INTENSIFICATION. IN THE
NEAR TERM, NUMERIC MODELS PREDICT SIGNIFICANT DEVELOPMENT FOLLOWING
A SLOW SOUTHEASTWARD PROGRESSION INTO THE CHANNEL. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1004 MB. IN VIEW OF THE CONTINUED
FAVORABLE ENVIRONMENT AND IN ANTICIPATION OF THE CYCLONE TRACKING
INTO OPEN WATER, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS HIGH. THIS
SUPERSEDES REF A.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
282000Z. //
=========================================================================
WTXS31 PGTW 20140328 21:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 21S (TWENTYONE) WARNING NR 001//
RMKS/
1. TROPICAL CYCLONE 21S (TWENTYONE) 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:
281800Z --- NEAR 12.8S 42.4E
MOVEMENT PAST SIX HOURS - 110 DEGREES AT 05 KTS
POSITION ACCURATE TO WITHIN 035 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: 12.8S 42.4E
---
FORECASTS:
12 HRS, VALID AT:
290600Z --- 13.5S 43.0E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 145 DEG/ 05 KTS
---
24 HRS, VALID AT:
291800Z --- 14.3S 43.6E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 140 DEG/ 04 KTS
---
36 HRS, VALID AT:
300600Z --- 14.9S 44.1E
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 - 065 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 135 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
301800Z --- 15.3S 44.5E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 230 DEG/ 01 KTS
---
72 HRS, VALID AT:
311800Z --- 15.6S 44.1E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 265 DEG/ 03 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
011800Z --- 15.7S 42.9E
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 120 HR POSIT: 265 DEG/ 03 KTS
---
120 HRS, VALID AT:
021800Z --- 15.8S 41.5E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
282100Z POSITION NEAR 13.0S 42.5E.
TROPICAL CYCLONE 21S (TWENTYONE), LOCATED APPROXIMATELY 462 NM
NORTHWEST OF ANTANANARIVO, MADAGASCAR HAS TRACKED EAST-
SOUTHEASTWARD AT 05 KNOTS OVER THE PAST SIX HOURS.
ANIMATED ENHANCED INFRARED SATELLITE IMAGERY (EIR) DEPICTS A
STEADILY CONSOLIDATING SYSTEM WITH DEEPENING CENTRAL CONVECTION
AND A FRAGMENTED BANDING FEATURE TO THE WEST OF THE LOW-LEVEL
CIRCULATION CENTER (LLCC). THE LLCC HAS CONTINUED MOVING FURTHER
OFFSHORE ALLOWING FOR THE RECENT DEVELOPMENT. A 281735Z SSMIS
IMAGE ALSO REVEALS MULTIPLE CURVED BANDS WRAPPING INTO THE SYSTEM
CENTER. THE INITIAL POSITION IS BASED ON THE 37 GHZ SSMIS IMAGE
AS WELL AS THE EIR WITH HIGH CONFIDENCE. THE INITIAL INTENSITY IS
ASSESSED AT 35 KNOTS BASED ON CONGRUENT DVORAK INTENSITY ESTIMATES
FROM PGTW, KNES, AND FMEE. UPPER-LEVEL ANALYSIS INDICATES THE SYSTEM
REMAINS IN A FAVORABLE ENVIRONMENT WITH LOW TO MODERATE (5-15 KNOT)
VERTICAL WIND SHEAR AND STRONG EASTWARD AND POLEWARD OUTFLOW
CHANNELS. ADDITIONALLY, WARM SEA SURFACE TEMPERATURES IN THE
MOZAMBIQUE CHANNEL ARE CONDUCIVE FOR FURTHER DEVELOPMENT. HOWEVER,
THE CYCLONES PROXIMITY TO THE AFRICAN LANDMASS MAY BE LIMITING THE
INFLUX OF MOISTURE NECESSARY FOR DEEP DEVELOPMENT. OVER THE PAST 48
HOURS A SERIES OF OUTFLOW BOUNDARIES HAVE BEEN OBSERVED IN
MULTISPECTRAL SATELLITE IMAGERY WHICH MAY BE AN INDICATOR OF THE
PRESENCE OF DRIER AIR IN THE MID-LEVELS. FOR THIS REASON THE SYSTEM
MAY STRUGGLE TO INTENSIFY OR MAINTAIN DEEPER DEVELOPMENT. TC 21S IS
FORECAST TO SLOWLY DRIFT TO THE SOUTHEAST IN A WEAK STEERING
ENVIRONMENT TOWARDS THE NORTHWEST COAST OF MADAGASCAR. AFTER THIS
AN ABRUPT TURN TO THE WEST IS ANTICIPATED DUE TO RIDGING BUILDING IN
TO THE EAST AND WEST OF THE CYCLONE. THE SYSTEM IS SUBSEQUENTLY
FORECAST TO WEAKEN DUE TO DEGRADING UPPER-LEVEL CONDITIONS AND
POTENTIAL LAND INTERACTION. DYNAMIC MODEL GUIDANCE IS IN FAIR
AGREEMENT INDICATING A MODERATE SPREAD IN TRACK SOLUTIONS
WITH THE EXCEPTION OF GFS, WHICH HAS CONSISTENTLY INDICATED A
SOUTHEAST TRACK OVER MADAGASCAR. DUE TO THE AMOUNT OF UNCERTAINTY
ASSOCIATED WITH THE WEAK STEERING ENVIRONMENT THE JTWC FORECAST
TRACK IS LAID CLOSE TO THE MULTI-MODEL CONSENSUS WITH LOW
CONFIDENCE. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 281800Z IS 10 FEET.
NEXT WARNINGS AT 290900Z AND 292100Z. THIS WARNING SUPERSEDES AND
CANCELS REF A, JOINT TYPHOON WRNCEN PEARL HARBOR HI 272000Z MAR
14 TROPICAL CYCLONE FORMATION ALERT (WTXS21 PGTW 272000).
=========================================================================
WTXS31 PGTW 20140329 09:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 21S (HELLEN) WARNING NR 002//
RMKS/
1. TROPICAL CYCLONE 21S (HELLEN) 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:
290600Z --- NEAR 13.0S 42.8E
MOVEMENT PAST SIX HOURS - 135 DEGREES AT 03 KTS
POSITION ACCURATE TO WITHIN 040 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 - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
REPEAT POSIT: 13.0S 42.8E
---
FORECASTS:
12 HRS, VALID AT:
291800Z --- 13.8S 43.5E
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 - 065 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 135 DEG/ 04 KTS
---
24 HRS, VALID AT:
300600Z --- 14.4S 44.1E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 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: 135 DEG/ 03 KTS
---
36 HRS, VALID AT:
301800Z --- 14.8S 44.5E
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
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 180 DEG/ 02 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
310600Z --- 15.1S 44.5E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 245 DEG/ 02 KTS
---
72 HRS, VALID AT:
010600Z --- 15.4S 43.8E
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 - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 255 DEG/ 03 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
020600Z --- 15.7S 42.5E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
290900Z POSITION NEAR 13.2S 43.0E.
TROPICAL CYCLONE 21S (HELLEN), LOCATED APPROXIMATELY 572 NM
NORTH-NORTHEASTWARD OF EUROPA ISLAND, HAS TRACKED SOUTHEASTWARD
AT 03 KNOTS OVER THE PAST SIX HOURS.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 290600Z IS 15 FEET. NEXT
WARNINGS AT 292100Z AND 300900Z.
=========================================================================
WTXS31 PGTW 20140329 21:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 21S (HELLEN) WARNING NR 003//
RMKS/
1. TROPICAL CYCLONE 21S (HELLEN) 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:
291800Z --- NEAR 13.4S 43.5E
MOVEMENT PAST SIX HOURS - 125 DEGREES AT 04 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 - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
REPEAT POSIT: 13.4S 43.5E
---
FORECASTS:
12 HRS, VALID AT:
300600Z --- 13.7S 44.0E
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 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 - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 130 DEG/ 03 KTS
---
24 HRS, VALID AT:
301800Z --- 14.1S 44.5E
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 - 065 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 155 DEG/ 02 KTS
---
36 HRS, VALID AT:
310600Z --- 14.5S 44.7E
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 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 - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 225 DEG/ 02 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
311800Z --- 14.8S 44.4E
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 - 065 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 240 DEG/ 04 KTS
---
72 HRS, VALID AT:
011800Z --- 15.5S 43.0E
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 - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 245 DEG/ 04 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
021800Z --- 16.2S 41.5E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 120 HR POSIT: 245 DEG/ 04 KTS
---
120 HRS, VALID AT:
031800Z --- 16.9S 39.8E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
292100Z POSITION NEAR 13.5S 43.6E.
TROPICAL CYCLONE (TC) 21S (HELLEN), LOCATED APPROXIMATELY 391 NM
NORTH-NORTHWEST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED
SOUTHEASTWARD AT 04 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED
INFRARED (EIR) SATELLITE IMAGERY DEPICTS A COMPACT SYSTEM AND
IMPROVED DEEP CENTRAL CONVECTION WITH TIGHTLY-CURVED BANDING
WRAPPING INTO A DEVELOPING LOW LEVEL CIRCULATION CENTER (LLCC). A
291723Z SSMIS MICROWAVE IMAGE ALSO REVEALS FORMATIVE BANDING TIGHTLY-
WRAPPED INTO A WELL-DEFINED LLCC. THE INITIAL POSITION IS BASED ON
THE SSMIS IMAGE AS WELL AS THE EIR LOOP WITH GOOD CONFIDENCE. THE
INITIAL INTENSITY OF 60 KNOTS IS BASED ON THE IMPROVING
STRUCTURE AND THE CONSENSUS OF DVORAK INTENSITY ESTIMATES RANGING
FROM 55 TO 65 KNOTS FROM PGTW, KNES AND FMEE. UPPER-LEVEL ANALYSIS
INDICATES THE SYSTEM IS LOCATED IN A FAVORABLE ENVIRONMENT WITH LOW
TO MODERATE (05 TO 15 KNOT) VERTICAL WIND SHEAR AND STRONG DUAL-
CHANNEL OUTFLOW, AS EVIDENT IN THE WATER VAPOR IMAGERY.
ADDITIONALLY, WARM SEA SURFACE TEMPERATURES IN THE MOZAMBIQUE
CHANNEL ARE CONDUCIVE FOR FURTHER DEVELOPMENT. THE FAVORABLE UPPER-
LEVEL ENVIRONMENT IS EXPECTED TO PERSIST THROUGH TAU 36, ALLOWING TC
21S TO RAPIDLY INTENSIFY AND LEADING TO A PEAK INTENSITY OF 95 KNOTS
BY TAU 36. TC HELLEN IS FORECAST TO CONTINUE SLOWLY DRIFTING
SOUTHEAST THROUGH TAU 36 ALONG A WEAK EXTENSION OF THE NEAR
EQUATORIAL RIDGE (NER) POSITIONED TO THE NORTHEAST. BY TAU 48, A
SUBTROPICAL RIDGE (STR) WILL BUILD IN FROM THE SOUTH, DOMINATING THE
STEERING ENVIRONMENT AND DRIVING TC 21S ON A WEST-SOUTHWESTWARD
TRACK. DYNAMIC MODEL GUIDANCE IS IN FAIR AGREEMENT WITH A TRACK TO
THE SOUTHEAST THROUGH TAU 36, BUT GREATLY DIVERGES AFTERWARDS DUE TO
A COMPETING ENVIRONMENT BETWEEN THE NER AND STR. DUE TO THE
UNCERTAINTY ASSOCIATED WITH THE WEAK STEERING ENVIRONMENT WHICH IS
CAUSING SLOW TRACK SPEEDS AND POSSIBLY QUASISTATIONARY AND ERRATIC
MOVEMENT IN THE NEAR TERM, THE JTWC FORECAST TRACK IS POSITIONED
CLOSE TO THE MULTI-MODEL CONSENSUS WITH LOW CONFIDENCE. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 291800Z IS 15 FEET. NEXT WARNINGS AT
300900Z AND 302100Z.//
=========================================================================
WTXS31 PGTW 20140330 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 21S (HELLEN) WARNING NR 004//
RMKS/
1. TROPICAL CYCLONE 21S (HELLEN) 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:
300000Z --- NEAR 14.1S 43.9E
MOVEMENT PAST SIX HOURS - 145 DEGREES AT 07 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 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 - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
REPEAT POSIT: 14.1S 43.9E
---
FORECASTS:
12 HRS, VALID AT:
301200Z --- 14.5S 44.3E
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 - 080 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT
115 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 130 DEG/ 02 KTS
---
24 HRS, VALID AT:
310000Z --- 14.8S 44.7E
MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
135 NM SOUTHEAST QUADRANT
130 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 130 DEG/ 02 KTS
---
36 HRS, VALID AT:
311200Z --- 15.1S 45.1E
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 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 - 075 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
105 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 215 DEG/ 02 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
010000Z --- 15.5S 44.8E
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
085 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 250 DEG/ 04 KTS
---
72 HRS, VALID AT:
020000Z --- 16.1S 43.1E
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 - 080 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 250 DEG/ 05 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
030000Z --- 16.8S 41.3E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 245 DEG/ 05 KTS
---
120 HRS, VALID AT:
040000Z --- 17.6S 39.5E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
300300Z POSITION NEAR 14.2S 44.0E.
TROPICAL CYCLONE (TC) 21S (HELLEN), LOCATED APPROXIMATELY 345 NM
NORTH-NORTHWEST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED SOUTHEASTWARD
AT 07 KNOTS OVER THE PAST SIX HOURS. MAXIMUM SIGNIFICANT WAVE HEIGHT
AT 300000Z IS 23 FEET. THE WARNING CYCLE HAS BEEN SHIFTED TO REFLECT
THE CURRENT INTENSITY OF 90 KNOTS DUE TO RAPID INTENSIFICATION OVER
THE PAST 6 HOURS. NEXT WARNINGS AT 301500Z AND 310300Z.//
=========================================================================
WTXS31 PGTW 20140330 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 21S (HELLEN) WARNING NR 005//
RMKS/
1. TROPICAL CYCLONE 21S (HELLEN) 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:
301200Z --- NEAR 14.7S 44.6E
MOVEMENT PAST SIX HOURS - 135 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 010 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
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
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
REPEAT POSIT: 14.7S 44.6E
---
FORECASTS:
12 HRS, VALID AT:
310000Z --- 15.3S 45.1E
MAX SUSTAINED WINDS - 140 KT, GUSTS 170 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 180 DEG/ 04 KTS
---
24 HRS, VALID AT:
311200Z --- 16.1S 45.1E
MAX SUSTAINED WINDS - 120 KT, GUSTS 145 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 - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT
115 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 235 DEG/ 04 KTS
---
36 HRS, VALID AT:
010000Z --- 16.5S 44.5E
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 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 - 100 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 245 DEG/ 04 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
011200Z --- 16.8S 43.8E
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 - 080 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 255 DEG/ 05 KTS
---
72 HRS, VALID AT:
021200Z --- 17.2S 41.9E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
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 - 075 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 265 DEG/ 05 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
031200Z --- 17.4S 39.8E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 275 DEG/ 06 KTS
---
120 HRS, VALID AT:
041200Z --- 17.2S 37.3E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
301500Z POSITION NEAR 14.9S 44.7E.
TROPICAL CYCLONE (TC) 21S (HELLEN), LOCATED APPROXIMATELY 290 NM
NORTH-NORTHWEST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED
SOUTHEASTWARD AT 04 KNOTS OVER THE PAST SIX HOURS. TC 21S HAS
RAPIDLY INTENSIFIED 80 KNOTS OVER THE PAST 24 HOURS, FROM 50 KNOTS
TO THE CURRENT INTENSITY OF 130 KNOTS, WHICH IS BASED ON DVORAK
INTENSITY ESTIMATES OF T6.5 (127 KNOTS) FROM ALL AGENCIES. ANIMATED
INFRARED SATELLITE IMAGERY DEPICTS AN 11-NM ROUND EYE SURROUNDED BY
A NEAR-SYMMETRIC, 130 NM DIAMETER EYEWALL. THE RAPID INTENSIFICATION
PHASE HAS BEEN FUELED BY EXCELLENT RADIAL OUTFLOW, EVIDENT IN
ANIMATED WATER VAPOR IMAGERY, AND FAVORABLE ENVIRONMENTAL
CONDITIONS. DESPITE WEAKENING OF OUTER CONVECTIVE BANDING DUE TO
LAND INTERACTION, A 301146Z SSMI IMAGE INDICATES THAT THE SYSTEM HAS
MAINTAINED AN INTENSE CORE OF CENTRAL CONVECTION. TC 21S IS TRACKING
SLOWLY SOUTHEASTWARD BUT IS FORECAST TO TURN SOUTHWARD BY TAU 24 AS
IT TRACKS ALONG THE WESTERN PERIPHERY OF THE SUBTROPICAL RIDGE
(STR). AFTER TAU 24, TC HELLEN WILL TURN WESTWARD AS THE STR BUILDS
TO THE SOUTH AND IS FORECAST TO MAKE LANDFALL OVER MOZAMBIQUE BY TAU
120. DYNAMIC GUIDANCE IS IN FAIR AGREEMENT WITH THE EXCEPTION OF
NAVGEM, WHICH ERRONEOUSLY DRIVES THE SYSTEM SOUTH-SOUTHWESTWARD INTO
THE STR. DESPITE THE GENERAL AGREEMENT ON THE FORECAST TRACK,
FORECAST CONFIDENCE REMAINS LOW DUE TO TIMING AND DEGREE OF THE
WESTWARD TURN WITH LAND INTERACTION FURTHER COMPLICATING THE SHORT-
TERM TRACK. TC 21S IS FORECAST TO CONTINUE INTENSIFYING TO A PEAK
INTENSITY OF 140 KNOTS BY TAU 12 (IN FACT, 1230Z IMAGERY SUPPORTS A
T7.0 WHICH EQUATES TO 140 KNOTS). NEAR TAU 12, THE SYSTEM CORE IS
EXPECTED TO BEGIN INTERACTING WITH LAND, WHICH SHOULD RESULT IN A
SHARP WEAKENING TREND THROUGH TAU 48. FURTHER WEAKENING IS EXPECTED
AS THE SYSTEM APPROACHES THE MOZAMBIQUE COAST AND ENCOUNTERS DRY AIR
ENTRAINMENT. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 301200Z IS 35 FEET.
NEXT WARNINGS AT 310300Z AND 311500Z.//
=========================================================================
WTXS31 PGTW 20140331 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 21S (HELLEN) WARNING NR 006//
RMKS/
1. TROPICAL CYCLONE 21S (HELLEN) 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:
310000Z --- NEAR 15.3S 45.4E
MOVEMENT PAST SIX HOURS - 130 DEGREES AT 05 KTS
POSITION ACCURATE TO WITHIN 030 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 - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
REPEAT POSIT: 15.3S 45.4E
---
FORECASTS:
12 HRS, VALID AT:
311200Z --- 15.8S 45.8E
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
105 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 210 DEG/ 03 KTS
---
24 HRS, VALID AT:
010000Z --- 16.3S 45.5E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 36 HR POSIT: 240 DEG/ 04 KTS
---
36 HRS, VALID AT:
011200Z --- 16.7S 44.7E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 48 HR POSIT: 250 DEG/ 05 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
020000Z --- 17.0S 43.7E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 260 DEG/ 05 KTS
---
72 HRS, VALID AT:
030000Z --- 17.3S 41.5E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 270 DEG/ 05 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
040000Z --- 17.3S 39.5E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 280 DEG/ 07 KTS
---
120 HRS, VALID AT:
050000Z --- 16.9S 36.6E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
310300Z POSITION NEAR 15.4S 45.5E.
TROPICAL CYCLONE 21S (HELLEN), LOCATED APPROXIMATELY 240 NM NORTH-
NORTHWEST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED SOUTHEASTWARD AT
05 KNOTS OVER THE PAST SIX HOURS. THE CURRENT POSITION IS BASED ON
RECENT SATELLITE FIXES FROM PGTW AND KNES. THE INTENSITY OF 125 KNOTS
IS CONSISTENT WITH DVORAK CURRENT INTENSITY ESTIMATES OF FROM THE
SAME REPORTING AGENCIES. TC 21S HAS BEGUN TO WEAKEN OVER THE PAST
SIX HOURS FOLLOWING A 24-HOUR PERIOD OF EXPLOSIVE DEEPENING. INTERACTION
WITH LAND AND ENTRAINMENT OF SLIGHTLY DRIER ENVIRONMENTAL AIR INTO
THE CIRCULATION CENTER APPEAR TO BE THE MAIN FACTORS DRIVING THE
RECENT WEAKENING TREND. TC 21S CONTINUES TO TRACK SOUTHEASTWARD ALONG
THE WESTERN PERIPHERY OF A SUBTROPICAL STEERING RIDGE TO THE EAST.
SLOW SOUTHEASTWARD MOTION IS EXPECTED TO PERSIST IN THE NEAR-TERM,
WITH THE CENTER OF TC 21S MAKING LANDFALL WEST OF MAHAJANGA IN ABOUT
12 HOURS. THEREAFTER, THE SYSTEM IS EXPECTED TO REMAIN INALND AND
TRACK OVER FAIRLY ROUGH TERRAIN FOR ABOUT 30 HOURS. CONSEQUENTLY,
POST-LANDFALL FORECAST INTENSITIES HAVE BEEN REDUCED SIGNIFICANTLY
FROM THE PREVIOUS WARNING. SHOULD THE CYCLONE TRACK EVEN FURTHER
INLAND THAN CURRENTLY FORECAST, IT MAY DISSIPATE BELOW WARNING
THRESHOLD CRITERIA (35 KNOTS) OVER NORTHWESTERN MADAGASCAR. ASSUMING
THE CYCLONE REMAINS INTACT, IT IS EXPECTED TO TURN WESTWARD UNDER THE
INFLUENCE OF A LOW T0 MID-LEVEL SUBTROPICAL RIDGE BUILDING
TO THE SOUTH AND TRACK WESTWARD OVER THE MOZAMBIQUE CHANNEL. LITTLE
INTENSITY CHANGE IS ANTIPATED AT THAT POINT AS MARGINAL UPPER LEVEL
CONDITIONS, PASSAGE OVER WARM WATER, AND DRY AIR ENTRAINMENT IMPACT
THE SYSTEM. NUMERICAL MODEL TRACK FORECAST GUIDANCE SUPPORTS SLOW
TRACK SPEEDS AND A GENERAL TURN TOWARD THE WEST OVER THE NEXT 24 HOURS,
FOLLOWED BY A WESTWARD TRACK ACROSS THE MOZAMBIQUE CHANNEL IF THE
CIRCULATION HOLDS TOGETHER. THE CURRENT FORECAST TRACK LIES CLOSE TO
THE MULTI-MODEL CONSENSUS, BUT CONFIDENCE IS LOW DUE TO POTENTIAL
DISSIPATION OVER LAND IN THE NEAR-TERM. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 310000Z IS 37 FEET. NEXT WARNINGS AT 311500Z AND 010300Z.//
=========================================================================
WTXS31 PGTW 20140331 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 21S (HELLEN) WARNING NR 007//
RMKS/
1. TROPICAL CYCLONE 21S (HELLEN) 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:
311200Z --- NEAR 16.2S 45.9E
MOVEMENT PAST SIX HOURS - 160 DEGREES AT 05 KTS
POSITION ACCURATE TO WITHIN 040 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
REPEAT POSIT: 16.2S 45.9E
---
FORECASTS:
12 HRS, VALID AT:
010000Z --- 16.7S 45.6E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 240 DEG/ 04 KTS
---
24 HRS, VALID AT:
011200Z --- 17.1S 44.9E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 36 HR POSIT: 240 DEG/ 04 KTS
---
36 HRS, VALID AT:
020000Z --- 17.5S 44.1E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 48 HR POSIT: 250 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
021200Z --- 17.9S 43.0E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 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 72 HR POSIT: 260 DEG/ 05 KTS
---
72 HRS, VALID AT:
031200Z --- 18.2S 41.1E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 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 96 HR POSIT: 275 DEG/ 06 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
041200Z --- 17.9S 38.4E
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: 290 DEG/ 07 KTS
---
120 HRS, VALID AT:
051200Z --- 16.9S 35.8E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
311500Z POSITION NEAR 16.3S 45.8E.
TROPICAL CYCLONE (TC) 21S (HELLEN), LOCATED APPROXIMATELY 180 NM
NORTH-NORTHWEST OF ANTANANARIVO, MADAGASCAR HAS TRACKED SOUTH-
SOUTHEASTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) INDICATES THAT TC 21S MADE
LANDFALL ABOUT 31/08Z AND HAS WEAKENED SIGNIFICANTLY. MSI CURRENTLY
SHOWS A PARTIALLY-EXPOSED YET TIGHTLY WRAPPED LOW-LEVEL CIRCULATION
CENTER (LLCC). A 311027Z NOAA-19 IMAGE INDICATES THAT THE BULK OF
THE DEEP CONVECTION IS CONFINED TO THE SOUTHERN SEMI-CIRCLE DUE TO
WEAK (10 TO 15 KNOTS) NORTHERLY VERTICAL WIND SHEAR. ADDITIONALLY,
ENTRAINMENT OF DRIER ENVIRONMENTAL AIR INTO THE CIRCULATION CENTER
APPEARS TO BE A FACTOR IN THE RECENT WEAKENING TREND. TC 21S IS
TRACKING ALONG THE WESTERN PERIPHERY OF THE SUBTROPICAL STEERING
RIDGE TO THE EAST. SLOW SOUTHWARD MOTION IS EXPECTED TO PERSIST IN
THE NEAR-TERM. THEREAFTER, THE SYSTEM IS EXPECTED TO REMAIN INLAND
AND TRACK OVER FAIRLY ROUGH TERRAIN FOR ABOUT 36 HOURS.
CONSEQUENTLY, TC 21S SHOULD CONTINUE TO RAPIDLY WEAKEN AND THERE IS
A POSSIBILITY THAT THE SYSTEM MAY DISSIPATE BELOW WARNING
THRESHOLD CRITERIA (35 KNOTS) OVER NORTHWESTERN MADAGASCAR.
ASSUMING THE CYCLONE REMAINS INTACT, IT IS EXPECTED TO TURN WESTWARD
UNDER THE INFLUENCE OF A LOW T0 MID-LEVEL SUBTROPICAL RIDGE BUILDING
TO THE SOUTH AND TRACK WESTWARD OVER THE MOZAMBIQUE CHANNEL BY TAU
36. LITTLE INTENSITY CHANGE IS ANTICIPATED OVER THE CHANNEL AS
MARGINAL UPPER LEVEL CONDITIONS, PASSAGE OVER WARM WATER, AND DRY
AIR ENTRAINMENT IMPACT THE SYSTEM. NUMERICAL MODEL TRACK FORECAST
GUIDANCE SUPPORTS SLOW TRACK SPEEDS AND A GENERAL TURN TOWARD THE
WEST OVER THE NEXT 24 HOURS, FOLLOWED BY A WESTWARD TRACK ACROSS THE
MOZAMBIQUE CHANNEL IF THE CIRCULATION HOLDS TOGETHER. THE CURRENT
FORECAST TRACK LIES CLOSE TO THE MULTI-MODEL CONSENSUS, BUT
CONFIDENCE IS LOW DUE TO POTENTIAL DISSIPATION OVER LAND IN THE NEAR-
TERM. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 311200Z IS 25 FEET. NEXT
WARNINGS AT 010300Z AND 011500Z.//
=========================================================================
WTXS31 PGTW 20140401 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 21S (HELLEN) WARNING NR 008//
RMKS/
1. TROPICAL CYCLONE 21S (HELLEN) 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:
010000Z --- NEAR 17.0S 46.1E
MOVEMENT PAST SIX HOURS - 160 DEGREES AT 05 KTS
POSITION ACCURATE TO WITHIN 060 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 LAND
REPEAT POSIT: 17.0S 46.1E
---
FORECASTS:
12 HRS, VALID AT:
011200Z --- 17.7S 45.7E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
010300Z POSITION NEAR 17.2S 46.0E.
TROPICAL CYCLONE (TC) 21S (HELLEN), LOCATED APPROXIMATELY 130 NM
NORTH-NORTHWEST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED SOUTH-
SOUTHEASTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED
SATELLITE IMAGERY (IR) REVEALS THAT TC HELLEN HAS RAPIDLY ERODED AS
THE LOW-LEVEL CIRCULATION CENTER (LLCC) HAS BECOME RAGGED AND THE
MAJORITY OF THE CONVECTION HAS SHEARED AWAY AND SHALLOWED. THE
SYSTEM IS EXPECTED TO STAY OVER MADAGASCAR FOR THE NEXT 36 TO 48
HOURS AND WILL DISSIPATE BELOW WARNING THRESHOLD IN THE NEXT 12
HOURS AS VERTICAL WIND SHEAR, DRY AIR, AND LAND INTERACTION CONTINUE
TO HAMPER THE SYSTEM. AFTER TAU 48, NUMERIC MODEL GUIDANCE IS
TRACKING TC 21S BACK OVER THE MOZAMBIQUE CHANNEL WITH A CHANCE OF
REGENERATION WHILE MOVING TOWARDS THE AFRICAN LANDMASS. THIS IS THE
FINAL WARNING ON THIS SYSTEM BY THE JOINT TYPHOON WRNCEN PEARL
HARBOR HI. THE SYSTEM WILL BE CLOSELY MONITORED FOR SIGNS OF
REGENERATION.//
Tropical cyclone tracks developed by Michael Bath using operational warnings and advisories.
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Document: tropical_cyclone_hellen_jtwc_advisories.htm
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