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Monthly Global Tropical Cyclone Summary January 1999
[Summaries and Track Data] [Prepared by Gary Padgett]
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Monthly Global Tropical Cyclone Summary January 1999 [Summaries and Track Data] [Prepared by Gary Padgett] |
MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY
JANUARY, 1999
(For general comments about the nature of these summaries, as well as
information on how to download the tabular cyclone track files, see
the Author's Note at the end of this summary.)
NOTE: I have been informed of another website where past editions of
the summaries and track files are archived. The owner of the site is
Michael Pitt, and the URL is:
http://www.qisfl.net/home/hurricanemike>
Thanks to Michael for archiving the summaries and for making me aware
of it.
***********************************************************************
1999 TROPICAL CYCLONE NAMES FOR THE NORTHWEST PACIFIC BASIN
Two lists of tropical cyclone names are used for the Northwest
Pacific basin, which is normally the most active of all the tropical
cyclone basins. The names most familiar to the international
community are the names assigned by JTWC (formerly located on the
island of Guam but now re-located to Pearl Harbor on the island of
Oahu in Hawaii). The Joint Typhoon Warning Center (joint between
the U. S. Air Force and Navy) was founded in 1959, but U. S. Navy
typhoon forecasters had been naming tropical cyclones in the Western
Pacific since at least 1945. For the most part, English feminine
names were used until 1979, when men's names were introduced and
alternated with women's names.
The other set of names are Filipino women's names, all ending with
the letters "ng", which are assigned by PAGASA for depressions and
storms which either form in or move into PAGASA's area of warning
responsibility. This practice dates back to 1963, and the names are
intended only for internal use within the Republic of the Philippines.
They are not attached to any international high seas warnings.
However, the winds of change are blowing. The year 1999 will be
the last year either of these lists of names are used. Beginning in
2000 a new truly international list of names will be introduced for
naming of tropical cyclones in this basin. Fourteen nations or
territories contributed 10 names each, and these will be allotted
to tropical cyclones as they reach tropical storm intensity by the
Japanese Meteorological Agency's Typhoon Warning Centre, which is the
WMO Regional Specialty Meteorological Centre (RSMC) for the region.
Names for 1999 are (an asterisk indicates name has already been
assigned since 1 Jan):
JTWC Names - Hilda *, Iris *, Jacob, Kate, Leo, Maggie, Neil, Olga,
Paul, Rachel, Sam, Tanya, Virgil, Wendy, York, Zia, Ann, Bart,
Cam, Dan, Eve, Frankie, Gloria, Herb, Ian, Joy, Kirk, Lisa, Marty,
Niki, Orson, Piper, Rick, Sally, Tom, Violet, Willie, Yates, Zane
PAGASA Names - Auring *, Bebeng *, Karing, Diding, Etang, Gening,
Helming, Ising, Luding, Mameng, Neneng, Oniang, Pepang, Rening,
Sendang, Trining, Ulding, Warling, Yayang, Ading, Barang, Krising,
Dadang, Erling, Goying
***********************************************************************
JANUARY HIGHLIGHTS
--> Vanuatu struck by damaging South Pacific cyclone
--> Southwest Indian Ocean season gets underway
***********************************************************************
ACTIVITY BY BASINS
ATLANTIC (ATL) - North Atlantic Ocean, Caribbean Sea, Gulf of Mexico
Activity for January: No tropical cyclones
***********************************************************************
NORTHEAST PACIFIC (NEP) - North Pacific Ocean East of Longitude 180
Activity for January: No tropical cyclones
***********************************************************************
NORTHWEST PACIFIC (NWP) - North Pacific Ocean West of Longitude 180
Activity for January: 1 tropical storm **
** - This based upon JTWC's classification--JMA and PAGASA did not
classify Hilda/Auring as a tropical storm.
NOTE: Most of the information on each cyclone's history presented in
the narrative will be based upon JTWC's advisories, and references to
winds should be understood as a 1-min avg MSW unless otherwise noted.
However, in the accompanying tracking document I have made comparisons
of coordinates with JMA (Japan) and the Philippines (PAGASA) when their
positions differed from JTWC's by usually 40-50 nm or more. Also, as
announced earlier in a separate posting, a column of 10-min avg MSW
is included--the values being obtained from either PAGASA's or JMA's
advisories. A special thanks to Michael V. Padua, owner of the Typhoon
'99 webpage, for sending me the PAGASA tracks.
In the title line for each storm I plan to reference all the cyclone
names/numbers I have available: JTWC's depression number and name (if
any), JMA's tropical storm numeric designator, and PAGASA's name for
systems forming in or passing through their area of responsibility.
Tropical Storm Hilda/Auring (TD-01W)
3 - 8 January
-------------------------------------
The first Northwest Pacific basin tropical cyclone of 1999 wasted
no time in making its appearance. As early as 1 Jan the Significant
Tropical Weather Outlooks issued by JTWC were mentioning a disturbance
in the extreme southern portion of the South China Sea west of Borneo.
JMA classified the LOW as a tropical depression at 1800 UTC on 3 Jan,
locating the ill-defined center about 350 nm southeast of Ho Chi Minh
City, Vietnam. The next bulletin, however, re-located the center
about 125 nm to the east. JTWC issued a Formation Alert for the
area at 0200 UTC on the 4th. The system was quite near the northwest
coast of Borneo and some mid-level dry air entrainment helped to
retard development of the depression. The first JTWC warning, issued
at 04/0600 UTC, estimated the center to be about 500 nm east-southeast
of Ho Chi Minh City. The initial intensity was set at 25 kts based
upon visible and infrared satellite imagery estimates and rawinsonde
data indicating 30 to 35-kt winds in the area from 600 to 1800 m.
The depression moved very slowly and erratically, generally drifting
very slowly northward and away from Borneo. The center was ill-defined
and difficult to track--a plot of the center positions from JTWC and
JMA look like randomly scattered dots. The tracking was made more
difficult by the presence of numerous weak low-level vortices embedded
within a broader circulation over the South China Sea. JTWC increased
the MSW to 30 kts at 0600 UTC on 5 Jan based upon a 0000 UTC ship
report of 30 kts northwest of the center.
A 06/0000 UTC report of 30-kt winds southwest of the center from
ship VSBZ as well as satellite intensity estimates of 30-35 kts were
the basis for upgrading the depression to Tropical Storm Hilda at
0600 UTC on the 6th. Hilda was at that time centered about 600 nm
southwest of Manila. The weak storm drifted slowly northward but
did not strengthen further. By 0000 UTC on 7 Jan the low-level
circulation had broadened considerably and resembled an elongated
trough. The deep convection was well northeast of the low-level
center and synoptic data from ships indicated winds of only 25 kts,
so Hilda was downgraded to a tropical depression and JTWC wrote the
final warning. JMA continued to track the residual depression on
through 08/0600 UTC as the weak system turned to a general easterly
direction toward the Philippine island of Palawan.
As would be expected with such an ill-defined system, there were
often significant discrepancies between JTWC's and JMA's positions.
PAGASA issued only three advisories on this system, naming it Auring.
Neither PAGASA nor JMA classified the depression as a tropical storm.
***********************************************************************
NORTH INDIAN OCEAN (NIO) - Bay of Bengal and Arabian Sea
Activity for January: No tropical cyclones
***********************************************************************
SOUTH INDIAN OCEAN (SIO) - South Indian Ocean West of Longitude 90E
Activity for January: 1 tropical disturbance
2 moderate tropical storms
1 severe tropical storm
The primary sources of information upon which the narrative is based
are the warnings issued by the TCWC on La Reunion Island, associated
with Meteo France, and which is the RSMC for the South Indian Ocean
basin. However, cyclones in this region are named by the sub-regional
centres on Mauritius and Madagascar with longitude 55E as the dividing
line between their respective areas. La Reunion only advises these
centres regarding the intensity of tropical systems. References to
sustained winds should be understood as meaning a 10-min averaging
period unless otherwise stated. In the accompanying track file
some position comparisons have been made with JTWC's positions, and
warnings from JTWC were used as a source of 1-min avg MSW estimates.
(A special thanks to Philippe Caroff of the La Reunion TCWC for
sending me an analyzed Best Track File for Alda, Birenda, and Chikita.
This information forms the basis for the tracking information given
for Alda and Birenda in the accompanying track file.)
Tropical Disturbance "A4"
4 - 6 January
-------------------------
A Tropical Weather Outlook issued by JTWC on 1 Jan mentioned an
area of convection near the coast of Mozambique. A large cyclonic
circulation was located near Zimbabwe and Mozambique with an upper-
level anticyclone over the area. The low-level circulation was
over land but drifting eastward toward the Mozambique Channel.
During subsequent days the area moved out over the warm waters of
the Channel, and the La Reunion TCWC initiated tropical disturbance
bulletins at 04/1200 UTC, placing the center about 225 nm northwest
of Tulear on the southeast coast of Madagascar. The bulletin
indicated that squally weather existed up to 250 nm from the center
in the northern and eastern sectors. Outflow was good over the eastern
half of the system but restricted on the western side where vertical
shear was inhibiting development.
The LOW moved generally in a south-southeasterly direction, passing
about 100 nm west of Tulear at 0000 UTC on 5 Jan. Maximum winds in
this disturbance as reported by La Reunion were 30 kts, but these
were mainly well away from the center in the eastern semi-circle and
associated with a strengthening gradient between the LOW and a ridge
to the southeast. The system passed a short distance southwest of
the southern portion of Madagascar early on the 5th. La Reunion
classified the disturbance as a subtropical cyclone at 1200 UTC and
as an extratropical depression six hours later as it began to
accelerate south-southeastwards into the South Indian Ocean.
Severe Tropical Storm Alda (TC-12S)
14 - 19 January
------------------------------------
The second disturbance to form in the Mozambique Channel in less
than two weeks was first mentioned by JTWC on 12 Jan. Deep convection
near the coast of Mozambique was forming near a shear line associated
with an extratropical LOW to the south. Synoptic data suggested that
a low-level circulation center was located farther inland with
convergence contributing to the deep convection. MSW at this time
were estimated to be only 15-20 kts.
By 14 Jan the area of deepest convection was out over the Channel
and La Reunion initiated warnings on the system, classifying it as
a subtropical cyclone due to the lack of persistent central convection.
Squally weather extended out from 200-300 nm to the south and east
of the center which was located about 450 nm west-northwest of Tulear.
The disturbance remained quasi-stationary for a day or so before
commencing a very slow eastward drift. Moderate vertical windshear
across the region initially kept the convection from organizing near
the center. By 16/0600 UTC the disturbance had reached the central
portion of the Mozambique Channel and had become slightly better
organized to the extent that La Reunion classified it as a tropical
disturbance.
The system turned slowly to the south and began to intensify,
becoming Tropical Storm Alda at 1800 UTC on the 16th. Neither JTWC
nor La Reunion expected the storm to intensify further, and JTWC
dropped warnings after 17/1500 UTC. Alda continued moving slowly
to the south, passing about 200 nm west of Tulear at 0000 UTC on
17 Jan. The JTWC warning for 17/1500 UTC noted that the satellite
current intensity was 25 kts but that there were reports from ships
of winds to 40 kts. Convection became much better organized on
the 17th, and satellite imagery at 18/0600 UTC showed an eye-pattern
in spite of the northwesterly shearing.
Alda reached its peak intensity of 50 kts at 1200 UTC on 18 Jan
when it was centered about 375 nm southwest of Tulear. After this,
however, the storm began to accelerate to the southeast and started
to lose its tropical characteristics. La Reunion declared Alda to
be extratropical and wrote the last warning at 0600 UTC on 19 Jan
with the center estimated to be about 700 nm east of Durban, South
Africa. (After dropping warnings on the storm at 17/1500 UTC, JTWC
issued one more warning at the time Alda reached its peak intensity.
JTWC's 1-min MSW estimate was 55 kts--in excellent agreement with
La Reunion's reported 10-min MSW of 50 kts.)
Severe Tropical Cyclone Damien/Birenda (TC-15S)
20 January - 7 February
------------------------------------------------
Weakening Tropical Cyclone Damien entered the South Indian Ocean
basin around 0600 UTC on 28 Jan at a point about 475 nm southwest of
Cocos Island and was renamed Birenda by the Mauritius Meteorological
Service. The early portion of this cyclone's history is discussed in
the section of this summary covering the Australian Region.
When it entered the basin Damien/Birenda was moving on a west-
southwesterly track which eventually turned into a more-or-less
westerly heading. By the 29th animated infrared and water vapor
imagery revealed that the upper-level cirrus from the convection was
being advected to the southeast in front of an approaching upper-level
trough. Birenda was downgraded to a tropical depression by 1200 UTC,
though JTWC still carried the system as a tropical storm through
1800 UTC on 30 Jan. By then the low-level circulation was completely
exposed and the nearest convection was in a convergent band 180 nm to
the west. The strongest winds were on the south side due to the
translational movement and the pressure gradient between the storm and
an anticyclone to the south.
The best track from La Reunion shows the weak remnants drifting
west-northwestward for a few days, finally being dropped at 03/0000
UTC when located about 750 nm east-northeast of Mauritius. JTWC
continued to mention the renmants for a few days in their daily
Tropical Weather Outlooks through 7 Feb when the system had merged
with a monsoon trough near 13S, 49E.
Tropical Storm Chikita (TC-17S)
29 January - 5 February
--------------------------------
A tropical disturbance following in the tracks of Damien/Birenda
moved from the western portion of the Australian Region across 90E
in late January. It began to intensify quite rapidly on 31 Jan and
was named Tropical Storm Chikita by Mauritius at 1200 UTC. Since
most of Chikita's lifespan occurred in February, it will be covered
in the February summary.
***********************************************************************
AUSTRALIAN REGION (AUG) - From Longitude 90E Eastward to Longitude 160E
Activity for January: 1 tropical LOW (depression)
2 tropical cyclones of storm intensity
1 severe tropical cyclone
The primary sources of information for Australian Region tropical
cyclones are the warnings and bulletins issued by the three TCWC's
at Perth, Darwin, and Brisbane. Information gleaned from JTWC's
warnings is used as a supplement for times when it was impossible to
obtain Australian bulletins and for comparison purposes. Additionally,
some information came from the Monthly Report of the RSMC at Darwin,
Northern Territory. References to sustained winds should be
understood as being based on a 10-min averaging period unless
otherwise noted.
Mr. Matthew Saxby, a tropical cyclone enthusiast from Queanbeyan,
New South Wales, Australia, is going to assist me with collecting
information and preparing tracks for tropical cyclones in the
Australian Region. Some of the information contained in the narratives
is based upon information forwarded to me by Matthew. A special
thanks to Matthew for his assistance.
Tropical Cyclone Olinda (TC-13P)
19 - 24 January
---------------------------------
A Significant Tropical Weather Outlook from JTWC at 0600 UTC on
19 Jan mentioned an area of disturbed weather south of the Solomon
Islands. Maximum winds at the time were estimated to be only around
25 kts (1-min avg). The system moved to the southeast and by 20 Jan
had gotten better organized. Brisbane located the center of the LOW
to be about 700 nm east of Cairns, or about 550 nm west-northwest of
Noumea, New Caledonia, at 1200 UTC. At the same time JTWC issued
the first warning on the system based on surrounding synoptic reports
of 25-kt winds (10-min avg). The depression had developed impressive
outflow with some spiral banding features. It still at this stage
had some monsoon depression characteristics in that maximum winds
were located along the outer periphery of the circulation.
The LOW drifted south-southeastward and slowly became better
organized. Later on 21 Jan the system began to organize rapidly into
a more consolidated system. Brisbane named the LOW Tropical Cyclone
Olinda at 1800 UTC when it was centered approximately 425 nm west-
northwest of Noumea. This position was just west of 160E and Olinda
had soon moved into Fiji's AOR and into the Southwest Pacific basin.
For a discussion of the remainder of Olinda's history, see the section
of this summary covering the Southwest Pacific basin.
Tropical Cyclone Pete (TC-14P)
20 - 27 January
-------------------------------
While the pre-Olinda system was getting organized on 20 Jan several
hundred miles east of the Australian coast, another area of disturbed
weather moved from northeastern Queensland out into the Coral Sea.
This LOW began to develop in tandem with the other disturbance farther
east and was named Tropical Cyclone Pete only 18 hours after Olinda
was christened. The LOW was centered about 200 nm east-northeast of
Cooktown at 0000 UTC on 21 Jan. According to the Monthly Summary from
Fiji, the depression executed an anti-clockwise loop late on the 21st.
A plot of the six-hourly coordinates does not definitively describe a
loop, so it must have been a very tight one. Following this wobble
the LOW began to move on a general southeasterly track very similar
to that taken by Olinda, lying southwest of and roughly parallel to
the earlier cyclone's path.
JTWC initiated warnings at 22/0600 UTC upon receipt of a ship report
of 40-kt winds. Brisbane named the system Tropical Cyclone Pete six
hours later when it was centered about 400 nm east of Cairns. Pete
continued to intensify some and reached its peak intensity of 50 kts
at 0600 UTC on the 23rd when it was located about 600 nm east of
Townsville. The cyclone continued on its southeastward course and had
moved out of the Australian Region by 24/0000 UTC. For a discussion of
the remainder of Pete's history, see the section of this summary
covering the Southwest Pacific basin.
Severe Tropical Cyclone Damien/Birenda (TC-15S)
20 January - 7 February
------------------------------------------------
A disturbance southwest of Sumatra associated with a monsoon
trough lying across the central Indian Ocean was noted in a Tropical
Weather Outlook from JTWC on 17 Jan. During the following days the
area of convection migrated slowly east-southeastward. Synoptic data
from ships indicated a weak, low-level circulation existed, and
satellite imagery indicated that the disturbance had good outflow to
the west. JTWC continued to mention the system in their daily
Outlooks, and Perth began issuing bulletins on the disturbance at
2200 UTC on 21 Jan. The LOW had drifted eastward south of Java and
by this time had become quasi-stationary about 600 nm northwest of
Onslow in Western Australia, or about 350 nm east-southeast of
Christmas Island.
On 22 Jan the LOW began moving west-southwestward under the
influence of a subtropical ridge to its south and slowly intensified
in a moderate shear environment. By 2200 UTC Tropical Cyclone Damien
had been christened about 200 nm southeast of Christmas Island. MSW
at this time were estimated at 45 kts. Damien continued on a west-
southwesterly course for the next few days and reached a peak intensity
of almost 80 kts around 24/2200 UTC when it was centered about 225 nm
south-southeast of Cocos Island. In satellite imagery the cyclone
alternated between displaying a clearly visible eye and an embedded
center pattern. However, the cyclone's peak intensity did not last
long. On the 25th Damien weakened considerably as convection waned
and vertical shear increased. Satellite images indicated that a large
field of cold-air stratocumulus had wrapped into the system, thereby
acting to decrease the central convection.
The cyclone turned to a temporary slow northwesterly course on
25 Jan which continued until the 27th. By 1600 UTC on that date Damien
was beginning to move southwestward once more. The weakening cyclone
crossed 90E into the Mauritius/La Reunion area of responsibility around
28/0600 UTC. MSW by this time were down to 40 kts and the low-level
center was fully exposed with the nearest convection about 70 nm to
the southwest. Synoptic data and a scatterometer pass indicated a
fairly large and symmetric 35-kt wind radius. Perth issued the last
warning at 0400 UTC on 28 Jan with Damien's center estimated to be
about 475 nm southwest of Cocos Island.
Upon entering the South Indian Ocean basin, the cyclone was renamed
Birenda by Mauritius. The latter part of this system's history is
discussed in the portion of this summary covering the South Indian
Ocean cyclone basin.
Tropical LOW (TC-16P)
22 - 27 January
----------------------
While Tropical Cyclones Olinda and Pete were racing southeastward
across the South Pacific, another disturbance was slowly getting
organized in the Gulf of Carpentaria. JTWC began mentioning the area
in their daily Tropical Weather Outlooks on 22 Jan. The disturbance
apparently drifted from north of Arnhem Land eastward into the
northern Gulf. The Darwin TCWC began issuing warnings on the LOW at
0600 UTC on 24 Jan when the system was centered about 115 nm east-
northeast of Nhulunbuy. A cyclone watch was posted at 0730 UTC for
portions of the southern Gulf Coast since it was anticipated that the
LOW would develop into a tropical cyclone within the next 24 hours.
JTWC issued a Formation Alert at 24/0930 UTC and began issuing warnings
at 0600 UTC on 25 Jan when the center was about 110 nm east of
Nhulunbuy or 175 nm northeast of Alyangula. The depression was located
within an elongated monsoon trough lying across northern Australia.
Over the next couple of days the system drifted very slowly in a
general southerly or south-southwesterly direction. It appeared to
get a little better organized on 25 Jan, but by the 26th had run into
some vertical shear and was weakening. The 26/2100 UTC warning from
JTWC noted that a second circulation appeared to be east of the warning
position and that dry air entrainment had led to decreased organization
of the depression.
The LOW was located 125 nm east of Alyangula at 0000 UTC on 26 Jan
and Darwin issued the last gale warning at 1800 UTC, although they
continued to issue Tropical Cyclone Advices for another 24 hours.
The final Advice from Darwin, at 27/1930 UTC, placed the weakening
center about 105 nm east-southeast of Alyangula or an equal distance
northeast of Port McArthur, moving slowly southeastward.
***********************************************************************
SOUTHWEST PACIFIC (SWP) - South Pacific Ocean East of Longitude 160E
Activity for January: 2 tropical cyclones of storm intensity
1 tropical cyclone of hurricane intensity
NOTE: Most of the information presented below was taken from the
operational warnings and advisories issued by the Fiji TCWC at Nadi
and from the Monthly Summary for January prepared by Alipate
Waqaicelua, Principal Scientific Officer and Chief of the forecasting
group. A special thanks to Alipate for sending the summary to me.
References to sustained winds imply a 10-minute averaging period
unless otherwise noted. Also, the basic definition of a cyclone in
WMO Region 5 (Australia and the South Pacific) has the unique
requirement that a depression must have gale-force winds more-or-less
completely surrounding the center before the system is named as a
tropical cyclone. Hence, often gales of 35-40 kts may be present in
one or two quadrants but the system is not considered a tropical
cyclone.
Fiji this season has initiated their own numbering scheme for
tropical disturbances (01F, 02F, etc) that form in the Nadi AOR.
Some of the numbered disturbances never warrant depression status.
A description of some of these weaker disturbances can be found
following the discussion of Tropical Cyclone Pete.
Tropical Cyclone Dani (TC-07F / TC-11P)
13 - 24 January
----------------------------------------
The first named South Pacific system of 1999 was a major cyclone.
The TCWC at Nadi, Fiji, identified a weak disturbance embedded in a
monsoon trough just south of the Solomon Islands on 13 Jan. The
disturbed area was drifting southeast. By 0600 UTC on 14 Jan the
system had become sufficiently organized that JTWC initiated warnings,
locating the center about 300 nm northwest of Port Vila, Vanuatu, with
35-kt MSW (1-min avg). The system continued to move generally
southwards off to the west of Espiritu Santo Island, the largest island
in the Republic of Vanuatu. By 15/0600 UTC convective organization
had increased significantly with the low-level center being covered
by deep convection which was cooling and expanding spatially. Most
TCWC's were by now giving the depression a Dvorak number of T=3.0,
so Nadi named the system Tropical Cyclone Dani, locating it about
200 nm west of Port Vila.
About the time that Dani reached tropical cyclone intensity, a
500-mb ridge to the south strengthened, thereby preventing any further
poleward movement. Dani drifted slowly to the west on the 16th as it
rapidly strengthened. Storm intensity (47 kts) was reached by 15/1800
UTC, and hurricane intensity six hours later. The cyclone had by this
time drifted westward to a point about 250 nm west of Port Vila. Dani
then began a slow northward motion as it came under the influence of
a mid-level anticyclone to its northwest. The cyclone reached its
peak intensity of 95 kts MSW (110 kts 1-min avg from JTWC) by 0000 UTC
on 17 Jan when it was centered about 325 nm west-northwest of Port
Vila or about 150 nm west of Espiritu Santo Island. Dani was by now
moving northward at a slightly faster pace and began to curve more to
the northeast as the anticyclone to its northwest extended a ridge to
the northeast. The storm also weakened slightly (to 80 kts), likely
due to interaction with a disturbance within the SPCZ.
As the ridge to the north strengthened Dani turned more to the east,
reaching the northernmost point of its track at 18/0000 UTC when it
was located 150 nm northwest of the northern tip of Espiritu Santo
Island. After this point the cyclone began turning slowly to the
south as the main steering influence shifted from the ridge to its
north to the mid-level ridge to its east and southeast. Dani moved
on a southeasterly course through 0000 UTC on the 19th, then turned
due south and struck the island of Espiritu Santo around 0300 UTC near
Hog Harbour with winds of hurricane intensity. Interaction with the
rugged terrain weakened the storm slightly, but it re-intensified back
to a MSW of 80 kts as it accelerated towards the south. The cyclone
brushed by the Vanuatuan islands of Malekula and Efate, passing about
50 nm west of Port Vila at 20/0000 UTC.
As Dani continued on to the south it approached the Loyalty Islands
which lie east of New Caledonia, passing very near Mare Island around
21/0000 UTC. After passing New Caledonia the cyclone began to
accelerate to the southeast and weaken as it came under increasing
vertical shear. Warning responsibility was passed to Wellington
after 1800 UTC, but Dani was declared extratropical by 22/0500 UTC.
JTWC issued its final warning about this time, noting that the
center was completely exposed (although well-defined) with the deep
convection located 70 nm to the northeast. The extratropical remnants
of Dani continued on to the southeast, passing about 425 nm east of
Norfolk Island around 2300 UTC on 22 Jan; then turning more to the
south, being last mentioned at 24/1100 UTC when located roughly
300 nm east of New Zealand's North Cape.
Steve Ready of the New Zealand Meteorological Service has passed
along some preliminary damage and casualty information he'd received
from Henry Taiki, the Director of the Vanuatu Meteorological Service.
A special thanks to Steve for sending me the information. There were
two deaths reported due to Tropical Cyclone Dani: one on Ambae Island
and one on Malekula. Bauefield Airport at Port Vila (on Efate Island)
recorded 545 mm in 24 hrs, including 312.4 mm between 0000 UTC and
0600 UTC on 20 Jan--the average January rainfall for Bauefield is
457 mm.
Hurricane force winds were experienced on Espiritu Santo and
Malekula and some nearby islands. Roads were badly damaged, and one
bridge was washed 200 to 300 metres from its location. Many houses of
lighter construction, plus some traditional homes, were destroyed.
River flooding was the major problem on Efate with 12 homes destroyed
in Vila by the La Colle river. Agricultural crops affected included
sweet potatoes, yams, tapioca, kava, and coconut.
Tropical Cyclone Olinda (TC-09F / TC-13P)
19 - 24 January
------------------------------------------
Tropical Cyclone Olinda formed in the eastern portion of the
Australian Region and was named by the Brisbane TCWC at 1800 UTC on
21 Jan when just west of the Fiji AOR. For the early history of this
cyclone see the section of this summary covering the Australian Region.
Olinda entered the Southwest Pacific basin shortly after being named
by Brisbane at a point about 400 nm west-northwest of Noumea. The
cyclone had MSW estimated at 45 kts and was already moving at a fairly
good pace toward the east-southeast. Olinda was approaching an area
of westerly shear and slightly cooler SSTs, but the steering flow was
an increasing deep-layer mean flow; and with environmental factors
being basically favorable for further intensification, the cyclone
continued to strengthen. Peak intensity of 55 kts was reached after
Olinda had passed into the Wellington AOR on 23 Jan.
While in Nadi's AOR Olinda did not directly threaten any populated
areas. The cyclone remained on a relatively steady east-southeasterly
trajectory which carried it about 150 nm southwest of New Caledonia.
Olinda passed about 150 nm south of Noumea at 23/0000 UTC just as it
was about to cross 25S into Wellington's AOR. The storm subsequently
turned to more of an easterly course and, as vertical shear increased,
began to lose tropical characteristics. The Wellington office deemed
Olinda extratropical at 1800 UTC on 23 Jan as it sped eastward, and was
last mentioned 24 hours later when the remnants were located about
525 nm south of Fiji.
Tropical Cyclone Pete (TC-10F / TC-14P)
20 - 27 January
----------------------------------------
Tropical Cyclone Pete formed in the Australian Region and was named
by the Brisbane TCWC at 1200 UTC on 22 Jan when it was centered about
400 nm east of Cairns, Queensland. For a discussion of the earlier
history of this cyclone, see the section of this summary covering the
Australian Region.
Pete entered Fiji's AOR at around 1800 UTC on 23 Jan at a point only
about 90 nm to the south of where Tropical Cyclone Olinda had crossed
160E forty-eight hours earlier. Pete entered the Southwest Pacific
basin at its peak intensity of 50 kts MSW and, like Olinda, moved at
a fairly quick pace towards the southeast under a northwesterly
steering current. The cyclone was being subjected to strengthening
westerly shear at this stage and was also racing into waters already
cooled somewhat by the passage of Olinda and Dani. At 24/0600 UTC it
started to turn east-southeast and six hours later was located near
the boundary with Wellington's AOR (25S). Warning responsibility
was handed over to Wellington in anticipation of Pete's continued
east-southeastward motion, but by 25/0000 UTC it was clearly evident
on visible satellite pictures that the center was back north of 25S.
Therefore, Nadi resumed issuing warnings as Pete headed east.
However, the environmental conditions had become quite unfavorable and
Pete steadily weakened. By late on the 25th the low-level center was
exposed and there was no deep convection. The cyclone had just crossed
the path where Tropical Cyclone Olinda had passed about two and a half
days earlier, and was forecast to reach Tropical Cyclone Dani's five
day-old path by 26/1200 UTC. Pete passed about 100 nm south of Noumea
around 1200 UTC on 25 Jan and continued drifting slowly eastward as it
weakened. The system was downgraded to a depression at 26/0600 UTC
but some gales continued in the southern and eastern quadrants for
another day or so. The last warning at 27/1800 UTC placed the center
about 200 nm southeast of Noumea. Tropical Cyclone Pete did not
approach any populated land areas during its lifetime.
Non-developing South Pacific Disturbances
-----------------------------------------
There were several tropical disturbances or weak depressions in the
Fiji AOR which were given sequence numbers but for which warnings were
not issued. TD-04F actually occurred in December, forming in the
Coral Sea in Brisbane's AOR on 25 Dec but moving southeast across 160E.
This system formed and remained in a strongly sheared environment and
by 26 Dec had dissipated. TD-05F formed on 1 Jan just north of the
Southern Cooks and moved slowly west-northwestward. Initially this
system had some baroclinic characteristics but later developed a fair
amount of convection. The depression was strongly affected by diurnal
effects, and by 3 Jan convection near the center had begun to decrease
as it came under southerly shear. The system had become unclassifiable
by 5 Jan. TD-06F was a small disturbance which formed on 3 Jan to the
southwest of French Polynesia. This system formed in an environment of
strong shear as it drifted slowly southwest, and never showed any
significant degree of organization.
The most significant non-developing disturbance was TD-08F which
formed on 16 Jan in an active convergence zone located just to the east
of Fiji. There were also other minor eddies along the convergence line
which was moving towards Fiji. From early on the 17th through the 19th
this convergence zone with embedded eddies moved across Fiji causing
the worst flooding event in this century, especially in the Northern
and Western (administrative) Divisions. The death toll was 6, and
damage to property, infrastructure, and crops reached $4 million in
Fijian dollars. A station in the western part of Viti Levu recorded
396 mm of rainfall in 24 hrs, which was a record for a non-cyclone
induced rain event.
After passing Fiji convective organization about the center
increased some, but vertical shear inhibited any significant
strengthening. By the 19th the disturbance had drifted to the
southwest of Fiji into much cooler waters and stronger northwest shear
which led to its demise.
***********************************************************************
EXTRA FEATURE
In order to shorten the amount of typing in preparing the narrative
material, I have been in the habit of freely using abbreviations and
acronyms. I have tried to define most of these with the first usage
in a given summary, but I may have missed one now and then. Most of
these are probably understood by a majority of readers but perhaps a
few aren't clear to some. To remedy this I developed a Glossary of
Abbreviations and Acronyms which I included in the July summary.
I will include this glossary from time to time, primarily in "lean"
months without a lot of tropical cyclone activity to cover. But if
anyone missed receiving it and wishes to obtain a copy, send me an
e-mail privately and I'll forward them a copy.
***********************************************************************
AUTHOR'S NOTE: This summary should be considered a very preliminary
overview of the tropical cyclones that occur in each month. The cyclone
tracks (provided separately) will generally be based upon operational
warnings issued by the various tropical cyclone warning centers. The
information contained therein may differ somewhat from the tracking and
intensity information obtained from a "best-track" file which is based
on a detailed post-seasonal analysis of all available data. Information
on where to find official "best-track" files from the various warning
centers will be passed along from time to time.
The track files are not being sent via e-mail. They can be retrieved
in the following manner:
(a) FTP to: hrd-type42.nhc.noaa.gov [140.90.176.206]
(b) Login as: anonymous
(c) For a password use your e-mail address
(d) Go to "data" subdirectory (Type: cd data)
(e) Set file type to ASCII (Type: ascii)
(f) Transfer file (Type: get remote_file_name local_file_name )
(The files will be named with an obvious nomenclature--using
January as an example: jan99.tracks)
(g) To exit FTP, type: quit
Both the summaries and the track files are standard text files
created in DOS editor. Download to disk and use a viewer such as
Notepad or DOS editor to view the files.
The first summary in this series covered the month of October,
1997. If anyone wishes to retrieve any of the previous summaries,
they may be downloaded from the aforementioned FTP site at HRD. The
summary files are catalogued with the nomenclature: jan99.sum, for
example.
Back issues can also be obtained from the following websites
(courtesy of Michael Bath, Michael V. Padua, Tom Berg, and Michael
Pitt):
http://australiansevereweather.com/cyclones/>
http://www.geocities.com/capecanaveral/6825>
http://www.hcane.com/tropcl.html>
http://www.qisfl.net/home/hurricanemike>
Another website where much information about tropical cyclones may
be found is the website for the UK Meteorological Office. Their site
contains a lot of statistical information about tropical cyclones
globally on a monthly basis. The URL is:
http://www.met-office.gov.uk/sec2/sec2cyclone/sec2cyclone.html>
Prepared by: Gary Padgett
E-mail: [email protected]
Phone: 334-222-5327 (nights & weekends) / 850-882-2594 (weekdays)
***********************************************************************
***********************************************************************
|
Document: summ9901.htm
Updated: 18th March 2008 |
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