MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY
FEBRUARY, 2005
Second Installment
(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.)
SPECIAL NOTE: The February summary is being issued in two installments.
The first installment covered the Southwest Indian Ocean basin and the
entire Australian Region and contained the Feature of the Month. This
second part is devoted to covering the unprecedented four very intense
tropical cyclones which traversed the South Pacific, all east of the
International Dateline.
*************************************************************************
FEBRUARY HIGHLIGHTS
--> Four very intense tropical cyclones form in Southeast Pacific
--> Strong Gulf of Carpentaria cyclone strikes Australia
--> One severe tropical storm in Southwest Indian Ocean basin
*************************************************************************
***** Feature of the Month for February *****
NOTE!!! The Feature of the Month was contained in the first installment
of the February summary.
*************************************************************************
ACTIVITY BY BASINS
ATLANTIC (ATL) - North Atlantic Ocean, Caribbean Sea, Gulf of Mexico
Activity for February: No tropical cyclones
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NORTHEAST PACIFIC (NEP) - North Pacific Ocean East of Longitude 180
Activity for February: No tropical cyclones
*************************************************************************
NORTHWEST PACIFIC (NWP) - North Pacific Ocean West of Longitude 180
Activity for February: No tropical cyclones
*************************************************************************
NORTH INDIAN OCEAN (NIO) - Bay of Bengal and Arabian Sea
Activity for February: No tropical cyclones
*************************************************************************
SOUTHWEST INDIAN OCEAN (SWI) - South Indian Ocean West of Longitude 90E
Activity for February: 1 tropical disturbance
2 tropical depressions
1 severe tropical storm
NOTE!!! The Southwest Indian Ocean basin was covered in the first
installment of the February summary.
*************************************************************************
NORTHWEST AUSTRALIA/SOUTHEAST INDIAN OCEAN (AUW) - From 90E to 135E
Activity for February: 1 tropical cyclone
NOTE!!! The Northwest Australia/Southeast Indian Ocean region was
covered in the first installment of the February summary.
*************************************************************************
NORTHEAST AUSTRALIA/CORAL SEA (AUE) - From 135E to 160E
Activity for February: 1 severe tropical cyclone
NOTE!!! The Northeast Australia/Coral Sea region was covered in the
first installment of the February summary.
*************************************************************************
SOUTH PACIFIC (SPA) - South Pacific Ocean East of Longitude 160E
Activity for February: 1 tropical depression
4 intense tropical cyclones of hurricane force
Sources of Information
----------------------
The primary sources of tracking and intensity information for
South Pacific tropical cyclones are the warnings and advisories
issued by the Tropical Cyclone Warning Centres at Nadi, Fiji (for
waters north of latitude 25S), and Wellington, New Zealand (for
waters south of latitude 25S). References to sustained winds imply
a 10-minute averaging period unless otherwise stated.
In the companion tropical cyclone tracks file, I occasionally
annotate positions from warnings issued by the Joint Typhoon Warning
Center (JTWC) of the U. S. Air Force and Navy, located at Pearl
Harbor, Hawaii, when they differ from the Southern Hemisphere
centres' coordinates by usually 40-50 nm or more. The JTWC warnings
are also the source of the 1-minute average maximum sustained wind
values included in the tracks file. Additionally, information
describing details of satellite imagery and atmospheric circulation
features included in the narratives is often gleaned from the JTWC
warnings.
South Pacific Tropical Activity for February
--------------------------------------------
February, 2005, was one of the most remarkable months ever in the
South Pacific tropical cyclone basin. Four intense tropical cyclones
formed, all east of the International Dateline. The only prior season
to have seen even three intense cyclones roam waters of the Southeast
Pacific during an entire season was in 1982-1983. Four intense cyclones
in this portion of the basin sets a new seasonal record--not to mention
a new monthly record--going back to 1960. (I am here defining the term
"intense cyclone" to mean a 10-min avg MSW of 90 kts or higher, which is
the criterion used by Meteo France in the Southwest Indian Ocean. This
is also equivalent to a 1-min avg MSW of 100 kts, which is essentially
the threshold for a Category 3 hurricane on the Saffir/Simpson scale.)
Many South Seas islands were adversely affected by Cyclones Meena,
Nancy, Olaf and Percy, ranging from Tokelau in the north to Rarotonga
in the south. Meena's punch was felt most keenly in the Southern Cooks
with Rarotonga being the most severely affected. The same general area
was the target of Nancy only a week later with Aitutaki Atoll, Rarotonga
and Mangaia being affected. Olaf and Percy besieged islands farther
north, with Olaf battering some islands in American Samoa while Percy
devastated the atolls of Tokelau, Swain's Island (belonging to American
Samoa), and Nassau and Pukapuka Atolls.
RSMC Nadi does not utilize a classification system for tropical
cyclones as do many TCWCs. To put these four Big Ones in perspective,
I thought I would classify them according to the Meteo France system
used for Southwest Indian Ocean cyclones, the Australian Cyclone Severity
Scale, and the Saffir/Simpson Scale utilized in the Atlantic and North-
east Pacific basins. If they had occurred in the Southwest Indian Ocean,
Meena and Nancy would have been classified as "intense tropical cyclones"
(MSW >= 90 kts) while Olaf and Percy would have been referred to as "very
intense tropical cyclones" (MSW > 115 kts). All four of the cyclones
reached Category 5 on the Australian scale. With regard to Saffir/
Simpson categories, Meena and Nancy would be strong Category 4 hurricanes
while Olaf and Percy would be classified as Category 5 hurricanes. Also,
Olaf and Percy would have been called super typhoons had they occurred in
the Northwest Pacific basin, and Meena was borderline--JTWC's highest MSW
was 125 kts (1-min avg), but Fiji's peak 10-min avg MSW of 115 kts
converts to 130 kts (1-min avg).
Excellent in-depth reports on these four remarkable cyclones follow,
all written by Simon Clarke of Cleveland, Queensland, Australia. A very
special thanks to Simon for his efforts.
A graphic displaying the combined tracks of Meena, Nancy, Olaf and
Percy can be found at the following link:
<http://www.tropicalcyclone2005.com/database/research/07F_10F_BT_2.gif>
Tropical activity in the South Pacific did not end with the four Big
Ones--there were some additional weaker systems near the end of the
month. Tropical Depression 11F formed on 26 February about 400 nm east-
southeast of Tahiti. The depression was never very well-organized and
drifted slowly eastward over the next day or so. The final summary on
the system, issued at 27/0600 UTC, placed it about 500 nm west-northwest
of Pitcairn Island.
A graphic displaying the track of this depression may be found at the
following link:
<http://www.tropicalcyclone2005.com/database/tc_besttracks_graphics/PACIFIC_
FIJI/2005_11F_BT.gif>
Two other disturbances were active as the month ended, both of these
becoming tropical depressions early in March. One of these, Tropical
Depression 12F, became the emphemeral Tropical Cyclone Rae on the 5th.
A short report on Rae will be contained in the March summary.
TROPICAL CYCLONE MEENA
(TD-07F / TC-15P)
2 - 8 February
------------------------------------------
A. Storm Origins
----------------
Meena was the fourth tropical cyclone of the season to form in the
Southwest Pacific for the 2004/2005 season. Meena was also the first
in a wave of intense tropical cyclones that were to develop in a very
active convective pattern which persisted through much of the western
to central South Pacific, including areas east of the Dateline, for
the entire month of February and into early March.
An area of low pressure was first identified moving westward on
1 February. At this time, Tropical Cyclone Lola was slowly decaying
some 600 nm to the southwest. After some consolidation, this area of
low pressure became quasi-stationary with a depression (designated
TD-07F by Fiji) becoming more clearly identifiable near 15.0S/168.0W,
or approximately 180 nm east of Pago Pago, American Samoa.
B. Synoptic History
-------------------
A small CDO was evident by 02/2100 UTC. The depression was within
a favourable environment for continued development, being located
just south of the upper-level (250-hPa) outflow in a region of strong
diffluence. The upper-level outflow in the northern region was
enhanced by strong cross-equatorial wind flow, but restricted
elsewhere. TD-07F was upgraded to cyclone status and named Meena at
03/0600 UTC near 14.4S/168.2W, or about 150 nm east of Pago Pago.
Meena then commenced a slow eastward path. Early development was
interrupted by northwesterly wind shear due to a shortwave upper-
level trough to the southwest and some misalignment between the LLCC
and the CDO. However, the cyclone started to slowly intensify as
outflow improved in all quadrants.
By 04/1200 UTC, organization had improved sufficiently for Meena to
possess hurricane force winds. The cyclone was then located
approximately 275 nm east of Pago Pago. A banding eye was also
discernible in visible satellite imagery. The cyclone turned to the
southeast at 10 kts and slowly accelerated in this direction, being
steered along the western periphery of a low to mid-level ridge
anchored to the southeast.
Meena intensified rapidly in the following 12 hours while passing
75 nm to the east of Palmerston Island and 100 nm to the west of
Aitutaki. Convective bands wrapped tightly around the CDO with tops
cooling to -86 C, and a well-defined eye was evident in satellite
pictures. The upper-level outflow remained good in all quadrants and
was enhanced in the southeast sector by a jet entrance region. By
06/1200 UTC, peak intensity of 915 hPa and 10-min avg winds of 115 kts
was reached and was maintained for the following six hours. Meena's
very destructive core was centered only about 100 nm northwest of
Rarotonga as it reached peak intensity and the eye subsequently passed
between Rarotonga and Managaia Island (21.9S/157.9W), moving to within
40 nm northeast of Rarotonga.
Thereafter, equatorward outflow decreased with steady erosion in the
deep convection in Meena's western semicircle. The fairly rapid
weakening process was enhanced by increasing vertical wind shear and
cooling SSTs. The cyclone moved into Wellington's AOR at 07/1200 UTC
and soon afterward merged with a baroclinic zone and was declared
extratropical at 08/0000 UTC near 28.0S/150.0W, or approximately 550 nm
south of Tahiti. The remnant LOW continued to accelerate to the
east-southeast at 30 kts into the empty Southeast Pacific. The final
reference to the ex-Meena LOW in Wellington's High Seas Bulletins at
08/1200 UTC placed the center a little over 850 nm southeast of
battered Rarotonga.
(Editor's Note: The peak 1-min avg MSW estimated by JTWC during Meena's
life was 125 kts, in good agreement with Fiji's 10-min avg peak MSW of
115 kts.)
A graphic displaying the track of Tropical Cyclone Meena may be
found at the following link:
<http://www.tropicalcyclone2005.com/database/tc_besttracks_graphics/PACIFIC_
FIJI/2005_07F-15P-MEENA_BT.gif>
C. Preliminary Damage Reports
-----------------------------
Residents living on Palmerston, Aitutaki, Rarotonga, Atiu, Mitiaro
and Mauke were reported as "counting themselves as lucky" as the
destructive core of Meena weaved its way between island groupings
without making a direct hit.
Palmerston Island reported that damage was limited to some coconut
trees and small huts being blown down, but otherwise no major damage.
Similarly, damage was light on Aitutaki with reports of felled
trees and houses losing roofing and other damage caused by debris.
There were no reports of injury.
With warnings that Meena was stronger than Tropical Cyclone Sally
which devastated Rarotonga on New Year's Day in 1987, the Government
of Rarotonga was well-prepared for Meena, setting up evacuation
shelters around the island for the island's 11,000 residents and 200
tourists. Preparation by households and businesses, and public
awareness, contributed to the minimal damage suffered. No injuries
or casualties were reported.
However, Meena's main punch was almost entirely due to the ocean
swell impacting on the fringing reef and coastline. The northern
coast of Rarotonga, especially in the commercial district of Avarua,
was pounded by huge waves early in the morning on 6 February. Waves
were reported to be averaging 14 metres in height. A strong storm
surge was experienced with widespread rocks strewn. The well-known
Trader Jacks Restaurant on the wharf at Avarua was reported as being
largely destroyed with only a shell of the building standing.
Moderate damage was reported to homes and businesses immediately on
or near the shore from the eastern part of Avarua eastward along the
east coast of the island. Government buildings on the east side
including the Ministry of Police and Health were damaged by the tidal
surge. Many residences near the coast also reported storm surge
damage. There was no significant damage reported to the airport.
Large amounts of debris were deposited along the coast and coastal
roads. Power and phone service remained functional throughout most
of the island with only isolated outages reported. Widespread damage
was reported to cooking sheds, trees and gardens, especially in
exposed coastal areas along the eastern coast. However, damage was
considerably less inland away from the coast and the tidal surge.
On Mangaia, the island's airport was strewn with rocks, the
harbour reported as being un-operational and in need of urgent
repairs, and the water distribution network was severely disrupted.
Inland roads were made inaccessible due to fallen trees.
At the time of writing this report, no estimates of damage had
been tallied from Meena.
D. Links
--------
Further photographs, reports and a basic plot of Meena's track can
be found at the Cook Island News website at:
<http://www.cinews.co.ck/Meena.htm>
TRMM Imagery is available at:
<http://www.eorc.nasda.go.jp/TRMM/typhoon/index_e.htm>
Further satellite pictures can be found at:
<http://www.nnvl.noaa.gov/cgi-bin/index.cgi?page=products&category=Year%2020
05%20Storm%20Events&event=Tropical%20Cyclone%20Meena>
(Report written by Simon Clarke)
TROPICAL CYCLONE NANCY
(TD-09F / TC-18P)
10 - 18 February
------------------------------------------
A. Storm Origins
----------------
Nancy was the fifth tropical cyclone to form in the Southwest
Pacific for the 2004/2005 season. Nancy was also the second in a
series of intense tropical cyclones that were to develop in the
western/central South Pacific. Nancy formed into a tropical cyclone
only four days after the demise of Tropical Cyclone Meena. Both
Nancy and Meena formed into tropical cyclones in almost the same
location to the east of American Samoa.
Also of interest, Nancy was named just prior to the next cyclone
in the series: Olaf, which was a developing depression (TD-08F) to
Nancy's near west. Both Nancy and Olaf became intense cyclone twins
reminiscent of Cyclones Ron and Susan during the 1997/1998 season.
A broad area of low pressure was first identified stretching from
Tuvalu across the central South Pacific to the north of Samoa as
early as 10 February 2005. Two centres of low pressure were
identified with the eastern LOW forming into TD-09F near 11S/168W, or
approximately 120 nm north-northeast of Pago Pago, American Samoa, at
10/2100 UTC. The depression's convection was concentrated around the
centre with improving organisation. The system was located just west
of an upper-level outflow in a low shear environment while SSTs
around the system were 30 C. The depression was quasi-stationary
initially, but a weak northwesterly steering flow was forecast to
drift the system to the south-southeast in the medium term.
B. Synoptic History
-------------------
Early development was hindered by an approaching trough from the
southwest which provided an increase in shear. However, by 12/0600
UTC organisation and outflow had improved with a small CDO developing
under the LLCC. At 12/1800 UTC TD-09F was upgraded to cyclone status
and named Nancy at 12.8S/166.8W, or approximately 300 nm east-
northeast of Pago Pago. Initial motion was to the northeast at about
5 kts. Nancy was located in a region of strong diffluence with good
outflow to the north and south and commenced the process of
intensification.
At 14/0000 UTC, the cyclone was located near 14.0S/164.0W, or
about 400 nm east of Pago Pago, and was moving to the southeast at
4 kts under the influence of a mid-level ridge to the east. This track
carried Nancy's center approximately 40 nm to the south of Suwarrow
Atoll. The cyclone had undergone rapid intensification in the
previous 12 hours and had developed hurricane force winds. Satellite
imagery revealed a symmetrical cloud pattern with an irregular but
warm eye. Further intensification followed as Nancy remained in a
region of strong diffluence assisted by twin outflow channels to the
north and southeast. Weak northwesterly vertical wind shear
persisted, but this did not limit further intensification as the
cyclone moved parallel to this shear.
Peak intensity of 935 hPa and 10-min avg winds of 110 kts was
achieved at 14/1200 UTC near 14.4S/162.1W, or approximately 100 nm
south-southeast of Suwarrow Atoll as the cyclone moved to the east-
southeast at 12 kts. A gradual turn to the south-southeast and south
ensued in the following 36 hours as Nancy crossed over the uninhabited
atoll of Manuae, situated almost midway between Aitutaki and Atiu.
Rapid weakening became evident as a result of increasing vertical wind
shear associated with a sharpening upper-level trough to the southwest.
Hurricane intensity was lost at 16/0600 UTC as the LLCC became exposed
30 nm from the main area of convection. By this time, Nancy had turned
to a southwesterly path at 10-12 kts as a result of interaction with
strengthening Tropical Cyclone Olaf situated to its northwest and passed
approximately 70 nm to the east and south of Rarotonga. Continued
interaction with Olaf resulted in Nancy's convective centre being
completely displaced toward the southwest away from the LLCC. By
17/0600 UTC, Nancy had transformed into an extratropical LOW near
25.0S/164.0W, or approximately 300 nm southwest of Rarotonga.
Convection was completely confined to the southern quadrant. The
remnant LOW moved into Wellington's AOR at this time and was soon
afterward absorbed into the outer circulation of intense Tropical
Cyclone Olaf to the north. The final reference to the ex-Nancy LOW
in Wellington's High Seas Bulletins was at 18/1200 UTC and placed the
35-kt gale centre about 500 nm southwest of Rarotonga.
(Editor's Note: JTWC's estimated peak 1-min avg MSW for Nancy was
125 kts. This is in excellent agreement with Fiji's peak 10-min
avg MSW of 110 kts.)
A graphic displaying the track of Tropical Cyclone Nancy may be
found at the following link:
<http://www.tropicalcyclone2005.com/database/tc_besttracks_graphics/PACIFIC_
FIJI/2005_09F-18P-NANCY_BT.gif>
C. Preliminary Damage Reports
-----------------------------
As with Meena only a week prior to Nancy, residents of the
Southern Cook Islands group were again "counting themselves as lucky"
as the destructive core of Nancy weaved its way between the inhabited
island groupings, and was considerably weakened prior to brushing
Rarotonga. However, when compared to Meena, it was wind damage
rather than sea surge damage that was notable, particularly to
residential premises.
On Aitutaki, Nancy uprooted trees, damaged roofs and flooded low-
lying areas on the atoll. With storm surges expected, many tourists
were moved to an evacuation centre on the atoll while radio
broadcasts called on villagers to evacuate the low-lying islands.
Cyclone shelters were open during the storm. As a result, no injuries
were reported among Aitutaki's 2000 residents.
One of the disaster management committee coordinators said that
the northeastern side of Aitutaki was hit by huge waves, with the
Samade Bar near the Ootu Peninsula experiencing flooding. Apart from
some debris, there was no damage to the airport. Strong winds
buffeted the island from late Monday afternoon and strengthened just
after midnight.
"We couldn't sleep," said Apii Porio, speaking on behalf of the
Atiu island secretary Charlie Koronui, the mayor Rakeimata Koronui,
and the local disaster management committee. "I think this is the
first time that people on Atiu have seen a cyclone like this."
Nearly 60 people sought refuge at the island's cyclone centres,
and Porio added that the strong winds and rain had left a lot of
houses with water damage. Porio estimated winds of up to 130 knots
(241 kph) struck the island between 1 AM and 5 AM on Tuesday morning,
ripping off the security doors at the island's power station, pushing
over power poles and leaving trees and branches on the roads right
around the island.
Destructive wind gusts (recorded up to 77 knots) were behind most
of the damage suffered around Rarotonga. Countless trees and
branches brought down power lines and littered the roads, while a
number of buildings--including classrooms at Tereora College and
Nikao Maori school, the CICC and Seventh Day Adventists' churches in
Matavera, and the Portofino Restaurant in Maraerenga--all lost their
roofs after midday.
Detective Senior Sergeant Are Ingaua, of the National Emergency
centre, said he thought Nancy was worse than Meena as it had caused
widespread destruction along the northern and eastern coasts of
Rarotonga.
"Roads have been flooded, trees uprooted and power lines blown down
by winds that gusted up to 185 km/hr.
"A couple of buildings have been destroyed, roofs have blown off
some schools, and in some homes only a concrete slab is left."
He said one of the three generators is operational and they may
have to operate in such a way that power is rationed fairly between
the villages. About seven houses lost their roofs along with the
Enua Manu pre-school, covers were blown off three community water
tanks, 15 cooking shelters demolished, and the northern side of the
island was pounded by heavy seas. However, no damage was reported at
the airport. At least two hotels on the island were closed
temporarily for repair work.
Mangaia was the last in the Cook Island Group to feel the effects
of Nancy with unofficial reports of gusts of up to 140 knots before
midday (15 February). People in Oneroa were moved to one of three
evacuation centres on higher ground, and heavy machinery was moved to
Makatea for the passage of the cyclone. There were no reports of
serious damage or injury, although one house in Ivirua reportedly had
its roof blown off.
Considerable crop damage was also reported throughout the Southern
Cook Islands associated with Nancy's winds.
NOTE: Further preliminary damage reports for the series of intense
South Pacific Cyclones from Meena to Percy will be summarised at the
end of the report on Tropical Cyclone Percy.
D. Links
--------
Further photographs, reports and a basic plot of Nancy's track can be
found at the Cook Island News website at:
<http://www.cinews.co.ck/Nancy.htm>
<http://www.nzaid.govt.nz/photo-library/pacific-cyclones.html>
A weakening Nancy, with strengthening Olaf at:
<http://www.redtailcanyon.com/items/758807.aspx>
(Report written by Simon Clarke)
TROPICAL CYCLONE OLAF
(TD-08F / TC-19P)
10 - 23 February
-----------------------------------------
A. Introduction
---------------
Olaf was the sixth tropical cyclone of the season to form in the
Southwest Pacific for the 2004/2005 season. Olaf was also the third
in a series of intense cyclones, which had commenced with Cyclone
Meena earlier in the month, and developed into a tropical cyclone
only twenty-one hours after the naming of its 'twin' cyclone, Nancy,
which had developed to its near east.
B. Storm Origins
----------------
By 10 February 2005 a broad area of low pressure had become
established in the central South Pacific stretching from Tuvalu
across to the north of Samoa. This area of disturbed weather spawned
two centres of low pressure with the western LOW forming into TD-08F
as early as 10/2100 UTC roughly 500 nm northeast of Fiji. The centre
of the depression was initially difficult to locate. However, by
13/0600 UTC, TD-08F had consolidated near 9.2S/177.6W (approximately
460 nm northwest of Apia, Western Samoa) into a common centre with
convection increasing in organisation and cooling about the central
area. Banding to the north developed and began to wrap around the
developing LLCC. Tropical Depression 08F was located in a region of
strong diffluence south of the 250-hPa outflow with SSTs of 30 C.
C. Synoptic History
-------------------
Olaf was named at 13/1500 UTC as winds reached 35 kts near the
centre. The newly-christened cyclone was near 9.2S/177.5W, or
roughly 500 nm northwest of Pago Pago, American Samoa. Initially,
the centre was difficult to fix and was relocated to near 9.4S/178.0W
at 13/1800 UTC. At this time, the cyclone was almost stationary and
commenced a phase of fairly rapid intensification under favourable
conditions consisting of low environmental shear and strong
diffluence aloft. Twelve hours later, at 14/0600 UTC, Olaf had
strengthened into a hurricane with 75-kt winds (10-min avg). By
15/0000 UTC the cyclone had become very intense with peak winds
estimated at 120 kts and a CP of 930 hPa and had commenced a steady
east-southeasterly movement at 8 kts. Olaf gradually turned
southeastward, accelerating to 10 kts as it was steered by the
equatorial northwesterlies. This track placed the Samoan Islands
under the serious threat of a potential direct strike.
The central pressure remained more or less within the 930-945 hPa
range for the following 24 hours as the cyclone jogged back to an
eastward track, moving approximately 100 nm north of Apia, Western
Samoa. By 16/0600 UTC, Olaf had intensified further with satellite
imagery depicting a well-defined and warming eye and convective tops
cooling to -80 C. Peak intensity of 125 kts/915 hPa was reached at
this time near 12.8S/171.1W, approximately 70 nm north-northeast of
Apia and 90 nm north-northwest of Pago Pago. The cyclone subsequently
reassumed a southeasterly track at around 15 kts. Maximum 10-min avg
winds of 115-125 kts were maintained until 18/0000 UTC at which time
Olaf reached a point near 19.7S/164.3W, or approximately 380 nm east-
southeast of Niue.
During this period, Olaf's eye passed approximately 15 nm to the
east of Ta'u, American Samoa, where a barometric pressure of 931 hPa
was recorded at 16/1654 UTC. It is possible that the pressure in the
centre of Olaf was as low as 900 hPa. However, the official track
summaries held the cyclone at a 915 hPa minimum central pressure.
Apia (WMO 91762, 13.80S/171.78W) recorded 124.9 mm of rain during
the 48-hour period from 15/0000 through 17/0000 UTC. (This bit of
information from Huang Chunliang.)
After 18/0000 UTC, increasing shear south of 20S ahead of an
approaching upper-level trough and dry air intrusion eroding
convection in the cyclone's southwest quadrant heralded a fairly
rapid weakening of Olaf as the system continued to accelerate to the
southeast through south-southeast and south at up to 20 kts. Convection
became displaced to the southeast of the LLCC as Olaf moved into
Wellington's AOR at 19/0000 UTC approximately 325 nm south-southwest
of Rarotonga. Olaf finally lost tropical cyclone status 18 hours later
near 31.0S/161.5W.
The extratropical remains of Olaf continued to track at up to 25 kts
in a general southeasterly direction into open ocean, re-intensifying as
a powerful 968-hPa extratropical system two days later. At 0000 UTC on
23 February the ex-Olaf extratropical system was a weakening 40-kt gale
centre crossing the 50th parallel about 1650 nm southwest of lonely
Pitcairn Island.
(Editor's Note: JTWC's estimated peak 1-min avg MSW for Olaf was
145 kts, in excellent agreement with Fiji's peak of 125 kts.)
A graphic displaying the track of Tropical Cyclone Olaf may be found
at the following link:
<http://www.tropicalcyclone2005.com/database/tc_besttracks_graphics/PACIFIC_
FIJI/2005_08F-19P-OLAF_BT.gif>
D. Preliminary Damage Reports
-----------------------------
Although the cyclone did not pass directly over Western Samoa,
winds of approximately 120-200 km/hr were reported to have damaged
power lines on the western island of Savai'i. Extensive tidal damage
was also reported in coastal areas. Faleolo International Airport
(NSFA/APW) in Apia was also closed during and after the cyclone.
Tropical Cyclone Olaf skirted around the northern side of the main
island of American Samoa, Tutuila, on February 15th and 16th (Samoan
local time) with wind speeds reaching more than 200 km/hr. However,
the Samoa National Disaster Council reported that no injuries or
major damage was sustained.
On American Samoa's Manua'a islands, Olaf destroyed many homes
close to the sea, downed crops and littered the island with debris.
Ale Filoialii, a resident on the Manua'a island of Ta'u, said nearly
all homes still standing had lost rooftops and the island was without
electricity and running water, creating health concerns. United States
President George W. Bush declared a major disaster in the Manu'a
island group. Territory Governor Togiola Tulafono advised that
President Bush's declaration meant assistance from the Federal
Emergency Management Agency would be available for the Manu'a group
which took the brunt of the cyclone. The Governor said the worst
affected area was the village of Fitiuta on Ta'u island which
suffered 85-90 per cent destruction. Houses had been destroyed,
trees snapped in two and a large section of road infrastructure wiped
out.
Mr. Tulafono reported that the most urgent need was to provide
clean water to the island of Ta'u where there was no electricity to
pump water from underground wells and the 100,000 gallon water tank
was nearly depleted. Although the power plant on the island was
working again, the lines between the villages of Ta'u and Fitiuta
were wiped out. "That area was totally devastated by the strength of
this wind," Mr. Tulafono said.
A spokesman from the American Samoan Power Authority said the lack
of water was creating health concerns. "We need to get water not
only for drinking but also to use in the homes--in the bathrooms and
toilets," he said.
Twenty-three people were rescued from the sea as a result of the
cyclone in the Samoan region, with two people reported as missing
from a fishing boat that sank. At the time of report writing, it is
not clear whether these two had been accounted for.
Unlike Cyclones Meena and Nancy, which skirted the east coast of
Rarotonga during the previous two weeks, Cyclone Olaf affected the
western side. Despite passing well to the west (approximately 125 nm),
there were reports of homes and businesses losing their roofs, and many
more had been left without power or phone lines. About 30-40 per cent
of homes on Rarotonga lost electricity and communications, but these
services were quickly restored. The Cook Islands Emergency Operations
Centre reported that approximately 60 houses on Rarotonga suffered
damage to their roofs.
On the island of Palmerston, sea water was reported to have surged
up to 100 meters inland as Cyclone Olaf passed by.
There were no reports of death or injury on land from Olaf.
NOTE: Further preliminary damage reports for the series of intense
South Pacific Cyclones from Meena to Percy will be summarised at the
end of the report on Tropical Cyclone Percy.
E. Links
--------
Further photographs, reports and a basic plot of Olaf's track can
be found at the Cook Island News website at:
<http://www.cinews.co.ck/OLAF.htm>
TRMM Imagery is available at:
<http://www.eorc.jaxa.jp/TRMM/typhoon/html/a/2005s/19P.OLAF_2005s_e.htm>
Further satellite pictures can be found at:
<http://www.nnvl.noaa.gov/cgi-bin/index.cgi?page=products&category=Year%2020
05%20Storm%20Events&event=Tropical%20Cyclone%20Olaf>
<http://rapidfire.sci.gsfc.nasa.gov/gallery/?2005047-0216/Olaf.A2005047.0110
.2km.jpg>
<http://rapidfire.sci.gsfc.nasa.gov/gallery/?2005047-0216/Olaf.A2005047.2125
.2km.jpg>
(Report written by Simon Clarke)
TROPICAL CYCLONE PERCY
(TD-10F / TC-20P)
24 February - 5 March
------------------------------------------
A. Storm Origins
----------------
Percy was the seventh tropical cyclone of the Southwest Pacific
for the 2004/2005 season and the final intense cyclone in a wave of
storms to affect the western to central South Pacific in the month of
February.
A discrete area of convection developed to the east of Tuvalu on
23 February with an area of low pressure soon forming into TD-10F
by 2100 UTC on the 24th. Being located in a favourable outflow
environment in all quadrants with high SSTs (31 C), the depression
underwent explosive development in the twelve hours leading up to
cyclone formation. Deep convection rotated around the LLCC and by
25/0000 UTC, TD-10F was upgraded to cyclone status and named Percy
near 8.5S/178.4W, or approximately 120 nm east of Fongafale, Tuvalu.
Percy was embedded in deep monsoonal westerly winds, and as a
consequence was being steered to the east-southeast at 14 kts.
B. Synoptic History
-------------------
Early development was described as being explosive with Percy
developing hurricane force winds by 25/1800 UTC when located
about 400 nm northwest of Pago Pago, American Samoa (near 9.0S/
175.0W). A ragged, cloud-filled eye became apparent in satellite
imagery and continued intensification was forecast as a shortwave
trough developed to the southwest of Percy. The cyclone indeed
intensified further as it passed midway between Fakaofa and Swains
Island, reaching its first peak in intensity of 100 kts/925 hPa at
27/0000 UTC approximately 215 nm north-northeast of Pago Pago (near
10.8S/169.6W). Percy adjusted to an eastward track and decelerated
as it ran into the middle-level ridge located to its east. Hereafter,
the cyclone's structure became somewhat asymmetric under the influence
of increasing northeasterly vertical wind shear and a slight weakening
trend persisted for the following 18 hours.
Between 27/1800 and 28/0000 UTC, Percy passed to the southwest of
and close to Pukapuka and Nassau Islands as a 940-hPa cyclone with
maximum 10-min avg winds of 85-90 kts. At this point, the cyclone
recommenced intensification as deep convection re-organised over the
CDO with the cloud pattern regaining a symmetrical pattern. An eye
soon re-appeared in EIR imagery. This re-intensification was
enhanced by a jet entrance region to the south as the cyclone turned
90 degrees to move on a slightly zigzag southerly path at 10 kts
around the western periphery of a mid-level ridge to the east.
The second peak intensity was achieved at 0000 UTC on 2 March when
the storm was located near 16.2S/165.3W, or roughly 275 nm south of
Nassau with a CP estimated at 900 hPa and a MSW of 125 kts. RSMC
Nadi noted that the warm pixel in Percy's eye registered 8 C in
satellite imagery with the CDO remaining tight with a cloud-free eye
and concentric eyewalls. Vertical shear was negligible over the system
as well as along its projected path. Accordingly Percy maintained
'super' cyclone status for a further 18 hours while moving to a
position approximately 110 nm west of Palmerston Island.
Weakening commenced thereafter as the eye began to cool and fill.
In a pattern established with the intense cyclones of the previous
weeks, a fairly rapid degeneration process followed as the cyclone
passed south of 20S as a result of an increase in vertical shear over
the system and a restriction in outflow over the northern quadrant.
Percy was shunted to the southeast by an approaching upper-level
trough, and eventually turned eastward after passing 24S as it was
captured by a deep trough approaching from the west. By 04/1200 UTC
the LLCC was detached to the northwest of the deep convection. Percy
was then located near 24.7S/158.6W, or approximately 230 nm south of
Rarotonga, with the overall convective structure of the cyclone
breaking up. Hurricane intensity was lost at this time and rapid
weakening ensued as the cyclone entered a belt of stronger westerlies.
Percy accelerated to the east at 20 kts, eventually becoming extra-
tropical at 05/0000 UTC near 26.0S/153.0W, or approximately 230 nm
south of Rimatara. The cyclone moved momentarily into RSMC Wellington's
AOR prior to losing cyclone status. The remaining extratropical
depression moved west-northwestward and continued to weaken further.
The final reference to the system by Wellington was at 1200 UTC on
5 March when it was located about 700 nm east-southeast of Rarotonga.
A graphic displaying the track of Tropical Cyclone Percy may be
found at the following link:
<http://www.tropicalcyclone2005.com/database/tc_besttracks_graphics/PACIFIC_
FIJI/2005_10F-20P-PERCY_BT.gif>
(Editor's Note: As was the case with Meena, Nancy and Olaf, JTWC's
peak estimated 1-min avg MSW was in good agreement with that from
Fiji. JTWC estimated Percy's peak winds at 140 kts at 0600 UTC on
2 March at the same time that Nadi was estimating the 10-min avg MSW
at 125 kts.)
C. Preliminary Damage Reports
-----------------------------
Percy severely battered the New Zealand-administered territory of
Tokelau, damaging roads and power lines and spreading debris around.
The 1400 people of Tokelau were faced with a massive clean-up job in
the wake of Cyclone Percy, which has been described as the worst to
hit the islands in living memory.
The island's administrator, Neil Walters, was in Tokelau when the
cyclone struck, coinciding with "king tides" that swamped the islands
in up to a metre of sea water. After a similar cyclone in 1966, much
of Tokelau's population was relocated to New Zealand. However, this
did not happen on this occasion as plans were already being made to
rebuild. "That's going to be pretty daunting, but again, people here
are tough and resilient and they'll get on with it," he said. "We'll
send up maintenance teams, whatever is needed to supplement what
they've got here."
The United Nations' Disaster Assessment and Coordination (UNDAC)
team in Tokelau reported that the Nukunono, Atafu and Fakaofa atolls
had lost significant parts of their infrastructure, including damage
from wind and floods to seawalls, hospital facilities, schools, an
office building and a meeting house, while debris had collected in
the villages.
The United Nations' emergency assessment teams further reported
that agriculture had been badly damaged in Tokelau. Tokelau's three
atolls lost most of their staple crops, especially the coconut crop
used for food and drink, the swamp taro, banana and pawpaw crops, while
most of the fish habitats were destroyed. The islands suffered beach
erosion and many live coral formations were covered by sand and debris.
Tokelau has received relief aid of $360,000 from New Zealand,
$39,000 from Australia and $50,000 from the United Nations'
Development Programme (UNDP), OCHA said.
Swain's Island, a small outlying part of American Samoa midway
between Hawaii and New Zealand, was out of contact for a week after
Percy hit. Following contact, all eight people on the island were
reported as being safe and well. That same evening a C-130 plane
flew from Pago Pago over Swains and dropped a load of food, water,
tents tarps and a first-aid kit. Of the nine buildings on the
island, only three survived Percy, including the Government Building
where the people took shelter during the storm. The island was
largely over-flooded by the storm surge, with very heavy damage
reported to gardens, trees and plants with debris strewn throughout.
According to Radio New Zealand International, nearly all of the
600 residents of Pukapuka and the 40 living on Nassau in the Northern
Cook Islands lost their homes or suffered heavy damage from the
cyclone, which hit after leaving damage in Tokelau and on Swains
Island in northern American Samoa. Only ten buildings were left
intact. Most displaced residents were reported to be staying in
churches and schools.
Pukapuka's head teacher noted that pupils could not go back to the
school unroofed by Cyclone Percy because of the raw asbestos roofing
material lying around. Pukapuka's water tanks and catchment areas
were polluted by seawater and needed to be cleaned before fresh
rainwater could be stored. Half the island's 600 people were reported
as living with neighbours while awaiting materials for rebuilding. A
team of 13 French soldiers assisted with the cleaning up process.
The island secretary urged authorities to urgently build community
water tanks on the two islands to guarantee clean water. He said
that most of the showers and toilets were damaged in the cyclone and
the heat had proved to be unbearable as shade trees had been knocked
down. Claims were soon made that a lack of sanitation on Pukapuka
and Nassau were becoming a health hazard in the wake of Cyclone Percy
and in early April, the Cook Island's Government was still
considering complete evacuation of Pukapuka because of a lack of
fresh food, water and shelter.
Reports indicate that only minor damage occurred on Palmerston
Island from Percy. Palmerston is a very small atoll with a population
of around 50 people. There are no cyclone proof buildings and local
residents usually wait out the storms in the interior part of the
largest island away from the storm surge. The population was cut off
from outside contact as the telecommunications link failed during Percy.
However, as Percy did not get any closer than 90 nm to Palmerston, the
population was spared from the full destructive force of the cyclone.
Police in Rarotonga reported no reports of damage or injuries as
Cyclone Percy passed well to the southwest of the island.
Deputy Prime Minister and Finance Minister Sir Geoffrey Henry
(Cook Islands) estimated that reconstruction costs from damage caused
by the four cyclones, including Percy, during the month of February
could be more than US$25 million.
D. Links
--------
Further photographs, reports and a basic plot of Percy's track can
be found at the Cook Island News website at:
<http://www.cinews.co.ck/Percy.htm>
TRMM Imagery is available at:
<http://www.eorc.jaxa.jp/TRMM/typhoon/html/a/2005s/20P.PERCY_2005s_e.htm>
Further satellite pictures can be found at:
<http://www.cinews.co.ck/Percy.htm>
<http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img
_id=12750>
Further in-depth materials on the damage situation following Percy can be
found at the ReliefWeb site at:
<http://www.reliefweb.int/rw/RWB.NSF/db900SID/EVIU-6AJJD8?OpenDocument>
A streaming news report from OneNews New Zealand regarding the situation
at Pukpuka can be found at:
<http://www.xtra.co.nz/streaming/0,,10979-4257912-300,00.html>
Snapshots of Percy's sea surge impact can be found at:
<http://www.dot.tk/vc00903.html>
(Report written by Simon Clarke)
*************************************************************************
SPECIAL FEATURE - SOURCES OF TROPICAL CYCLONE INFORMATION
The purpose of this section is to list some websites where many and
varied types of tropical cyclone information are archived. Many readers
will know about these already, but for the benefit of those who don't,
I wanted to include them.
(1) Aircraft Reconnaissance Information
---------------------------------------
Various types of messages from reconnaissance aircraft may be
retrieved from the following FTP site:
<ftp://ftp.nhc.noaa.gov/pub/products/nhc/recon/>
Information regarding how to interpret the coded reconnaissance
messages may be found at the following URL:
<http://www.nhc.noaa.gov/reconlist.shtml>
Links are also included to websites with further information about the
U. S. Air Force 53rd Weather Reconnaissance Squadron and the NOAA Air-
craft Operations Center.
(2) Archived Advisories
-----------------------
All the advisory products (public advisories, forecast/advisories,
strike probabilities, discussions, various graphics) issued by TPC/NHC
are archived on TPC's website. For the current year (using 2004 as an
example), the archived products can be found at:
<http://www.nhc.noaa.gov/archive/2004/index.shtml>
Links to tropical products archives for earlier years are available at
the following URL:
<http://www.nhc.noaa.gov/pastall.shtml>
JTWC warnings for past storms are archived on the NRL Monterry website:
<http://www.nrlmry.navy.mil/tc_pages/tc_home.html>
On the NRL site, the link to past years can be found in the upper left
corner of the screen.
I am not aware at the moment of any other TCWC which archives all
its tropical cyclone warning/advisory products for public access, but
if I learn of any, I will add them to this list.
(3) Satellite Imagery
---------------------
Satellite images of tropical cyclones in various sensor bands are
available on the NRL Monterrey and University of Wisconsin websites,
courtesy of Jeff Hawkins and Chris Velden and their associates. The
links are:
<http://www.nrlmry.navy.mil/tc_pages/tc_home.html>
<http://cimss.ssec.wisc.edu/tropic/tropic.html>
On the NRL site, the link to past years can be found in the upper left
corner of the screen. For the CIMSS site, a link to data archives is
located in the lower left portion of the screen.
I'm sure there are other sites with available imagery available, and
as I learn of them, I will add the links to this list.
*************************************************************************
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 first included in the August, 1998
summary. I don't normally include the Glossary in most months in
order to help keep them from being too long. If anyone would like to
receive a copy of the Glossary, please e-mail me and I'll be happy
to send 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
from the archive sites listed below. (Note: I do have a limited e-mail
distribution list for the track files. If anyone wishes to receive
these via e-mail, please send me a message.)
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. Back issues can be obtained from the following websites
(courtesy of Michael Bath, Michael V. Padua, Michael Pitt, Chris
Landsea, and John Diebolt):
<http://australiasevereweather.com/cyclones/>
<http://www.typhoon2000.ph>
<http://mpittweather.com>
<ftp://ftp.aoml.noaa.gov/hrd/pub/landsea/padgett/>
<http://www.tropicalcyclone2005.com/>
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.metoffice.gov.uk/weather/tropicalcyclone>
TROPICAL CYCLONE REPORTS AVAILABLE
JTWC now has available on its website the Annual Tropical Cyclone
Report (ATCR) for 2004 (2003-2004 season for the Southern Hemisphere).
ATCRs for earlier years are available also.
The URL is: <http://199.10.200.33/jtwc.html>
Also, TPC/NHC has available on its webpage nice "technicolor"
tracking charts for the 2004 Atlantic and Eastern North Pacific
tropical cyclones; also, storm reports for all the 2004 Atlantic
and Eastern North Pacific cyclones are now available, as well as
track charts and reports on storms from earlier years.
The URL is: <http://www.nhc.noaa.gov>
A special thanks to Michael Bath of McLeans Ridges, New South Wales,
Australia, for assisting me with proofreading the summaries.
PREPARED BY
Gary Padgett
E-mail: garyp@alaweb.com
Phone: 334-222-5327
Kevin Boyle (Eastern Atlantic, Western Northwest Pacific, South
China Sea)
E-mail: newchapelobservatory@btinternet.com
John Wallace (Assistance with Eastern North Pacific)
E-mail: dosidicus@aol.com
Huang Chunliang (Assistance with Western Northwest Pacific, South
China Sea)
E-mail: huangchunliang@hotmail.com
Simon Clarke (Northeast Australia/Coral Sea, South Pacific)
E-mail: saclarke@iprimus.com.au
*************************************************************************
*************************************************************************
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