SUMMARY: February Tropical Cyclone Summary - Part 2

From: Gary Padgett (garyp@ALAWEB.COM)
Date: Tue Apr 08 2003 - 08:39:53 EDT


                   MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY

                              FEBRUARY, 2003
                                  Part 2

  (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: The February summary is being issued in two installments. The
  first part covered the Southwest Indian Ocean basin. This second part
  covers the Australian Region and the South Pacific basin, and contains
  the Feature of the Month.

  *************************************************************************

                           FEBRUARY HIGHLIGHTS

  --> Twin tropical cyclones in Southwest Indian--one brushes Mauritius
  --> First named Australian cyclones of season form
  --> Very intense cyclone forms in Southeast Pacific
  --> Damaging tropical cyclone strikes Mozambique

  *************************************************************************

               ***** Feature of the Month for February *****

              SOUTHERN HEMISPHERE TROPICAL CYCLONE STATISTICS
              -----------------------------------------------

     For this month's feature I am highlighting a compilation of various
  statistics on Southern Hemisphere tropical cyclones (TCs) prepared by
  Patrick Hoareau of Rennes, France. These can be accessed on Michael
  Bath's website:

     <http://australiasevereweather.com/cyclones/stats.htm>

     One caveat is in order: Patrick based his work entirely on JTWC's
  Best Track database, so this should be kept in mind when comparing his
  statistics with those of the official WMO warning centres or any other
  such study.

     Several different types of charts or categories of charts are
  available, and I have detailed these below:

   (1) Monthly distribution of all tropical cyclones

       This chart covers the period 1969/1970 through the 2001/2002 season,
       and lists the number of TCs (including depressions) for which JTWC
       issued warnings by month. The most active season was 1996/1997 when
       38 TCs developed; the two least active seasons were 1987/1988 and
       2000/2001 when only 21 TCs were tracked by JTWC. The single most
       active month was January, 1975, when 14 TCs were charted.

   (2) Distribution of tropical cyclones at maximum intensity

       This chart covers from the 1982/1983 season to the present and lists
       the seasonal totals of TCs reaching a 1-minute average MSW of
       35 kts, 65 kts, 100 kts, 120 kts, and 130 kts. The peak number of
       intense TCs (MSW of 100 kts or greater) was 11, and was reached in
       1991/1992 and in 1993/1994.

       NOTE: The current total (as of 08 April) for the 2002/2003 season
       is also 11, thus tying the two seasons referenced above. The
       intense TCs so far this season have been Zoe, Ami, Beni, Dovi, Erica
       and Eseta in the South Pacific Ocean; and Gerry, Fiona, Japhet,
       Kalunde and Inigo in the South Indian Ocean. Five of these
       systems (Zoe, Dovi, Erica, Kalunde and Inigo) reached JTWC's "super
       typhoon" intensity of 130 kts, and Beni came very close (125 kts).

   (3) Distribution of tropical cyclones at maximum intensity in the
       Southern Indian Ocean

       This chart is similar to (2) but covers the South Indian Ocean,
       i.e., from the African coast to longitude 135E.

   (4) Distribution of tropical cyclones at maximum intensity in the
       South Pacific Ocean

       Identical to (3) except for the region 135E eastwards to the
       South American coast.

   (5) Start date and end date of tropical cyclone seasons

       This interesting chart contains information on TC seasons for the
       period 1984/1985 through 2001/2002. Items tabulated include the
       starting date of the season, number of early season TCs (forming
       before 1 January), end of season dates, overall number of TCs,
       and the number of warnings issued (by JTWC). The earliest starting
       seasons were those of 1989/1990 and 1996/1997 which began on
       10 July. The latest ending season was 1986/1987 which ended on
       27 June. The largest number of early season TCs was 13 during the
       1996/1997 season.

   (6) Mean number of hurricane/typhoon intensity tropical cyclones
       by month

   (7) Strongest tropical cyclones

       This chart is based on the period 1980/1981 through 2001/2002 and
       lists all the TCs which reached a MSW of 120 kts per JTWC's
       analysis. The most intense for the entire Southern Hemisphere was
       Tropical Cyclone Agnielle in the South Indian Ocean in November,
       1995, which was analysed to have peaked at 150 kts. The most
       intense TC for the South Pacific listed is Tropical Cyclone Ron in
       January, 1998, which peaked at 145 kts. The only other TC which
       reached 145 kts was Tropical Cyclone Geralda in January, 1994.

       NOTE: If the operational intensity of 155 kts for the recent
       Tropical Cyclone Zoe stands in post-storm analysis, Zoe will become
       the new record-holder for the Southern Hemisphere and the South
       Pacific. Tropical Cyclone Ron, however, still holds the record for
       the most intense TC east of the Dateline in the South Pacific.

   (8) Strongest tropical cyclones by month

   (9) Average early and late season tropical cyclones by basin

  (10) Average genesis, peak intensity and cyclolysis (death) by basin

       This section consists of a series of annual charts covering the
       period 1982/1983 through 2000/2001 and gives the average number of
       formations, peak intensities, and dissipations occurring in six
       "basins", probably more aptly called "sub-basins":

       (a) Africa to 70E
       (b) 70E - 100E
       (c) 100E - 135E
       (d) 135E - 180
       (e) 180 - 150W
       (f) 150W to South America

  (11) Best track summary

       For the period 1993/1994 through 2000/2001, this gives the average
       number of synoptic times (6-hourly data points) with the MSW in
       various intensity ranges, e.g., tropical storm, hurricane, etc.

  (12) Best tracks for individual seasons

       Annual charts for 1993/1994 through 2000/2001, listing each TC with
       similar information as in item (11).

     I referred to Patrick's statistics in a monthly feature last year
  (May) when I highlighted some of my friends TC-related websites.
  Hopefully this more detailed description of Patrick's work will
  encourage interested persons to visit Michael's great website and
  explore Patrick's charts as well as some of the wealth of additional
  information Michael has made available.

  *************************************************************************

                            ACTIVITY BY BASINS

  ATLANTIC (ATL) - North Atlantic Ocean, Caribbean Sea, Gulf of Mexico

  Activity for February: No tropical cyclones

  *************************************************************************

  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 moderate tropical storm
                          1 tropical cyclone
                          2 intense tropical cyclones

  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 LOW
                          1 tropical cyclone of gale intensity
                          1 severe tropical cyclone (hurricane)

                Northwest Australia/Southeast Indian Ocean
                      Tropical Activity for February
                ------------------------------------------

     Two tropical cyclones formed in waters off Western Australia during
  February. The first, Fiona, was the first tropical cyclone of the
  current season to be actually named by any of the Australian TCWCs,
  although an unnamed system in January was determined in post-analysis
  to have reached tropical cyclone status twice during its history. Fiona
  became an intense tropical cyclone (10-min avg MSW 90 kts or greater)
  but remained over the open waters of the Southeast Indian Ocean and
  did not affect any land areas. Near the end of the month a much weaker
  Tropical Cyclone Graham formed north of the Port Hedland area and moved
  inland about 160 km southwest of Broome on the 28th.

     A couple of other tropical LOWs deserve some mention. The first
  formed approximately 125 nm northeast of the Cocos Islands on the 4th.
  Gale warnings were issued by Perth for a couple of days in anticipation
  that the system would strengthen, but there are no indications from
  the text of the warnings that any actual gales, central or peripheral,
  were observed. The LOW moved slowly westward and the final bulletin
  from Perth at 0400 UTC on the 6th placed it about 200 nm west-northwest
  of Cocos. There is a possibility that this system was the progenitor
  of Tropical Storm Isha which formed west of 90E on 11 February. Another
  weak tropical LOW was noted in the Perth Tropical Weather Outlooks on
  the 24th and 25th of February. This system was located about 270 nm
  southwest of Christmas Island on the 24th and was initially assessed to
  have a moderate chance of developing into a tropical cyclone, but the
  system subsequently weakened after the 25th.

                       SEVERE TROPICAL CYCLONE FIONA
                                 (TC-14S)
                              4 - 13 February
             -------------------------------------------------

  A. Storm Origins
  ----------------

     An area of convection developed and persisted on 3 February about
  575 nm north-northwest of Port Hedland, Western Australia. Animated
  multi-spectral imagery showed poorly-defined convection near a weak
  LLCC, and a 200-mb analysis revealed good outflow over the disturbance.
  The system drifted slowly westward on the 4th without much change in
  organization until around 2000 UTC, when animated infrared imagery showed
  an increase in convection near the LLCC. JTWC correspondingly upgraded
  the potential for development to fair. An upper-level analysis showed
  good diffluence and weak to moderate vertical shear. At 2200 UTC the
  Perth TCWC issued the first gale warning on the developing tropical LOW,
  placing the center approximately 625 nm north-northwest of Onslow in
  Western Australia. JTWC issued a TCFA at 0500 UTC on 5 February, and
  at 0700 UTC Perth named the system Tropical Cyclone Fiona, then located
  approximately 350 nm east-southeast of Christmas Island. Fiona was
  tracking westward with the MSW estimated at 40 kts (10-min avg).

  B. Track and Intensity History
  ------------------------------

     JTWC issued their first warning on Fiona (TC-14S) at 1200 UTC on
  5 February, estimating the 1-min avg MSW at 35 kts. CIMSS data indicated
  good outflow aloft and a weak vertical shear environment, so conditions
  appeared favorable for Fiona to strengthen significantly. The cyclone
  was forecast to track generally westward under the steering influence
  of a ridge to the south. Fiona intensified steadily--at 06/1200 UTC
  both JTWC and Perth were estimating the intensity at 55 kts. The remarks
  in the JTWC warning well illustrate the vagaries of cyclone intensity
  estimation by remote sensing. At that hour the CI estimates available
  to JTWC ranged from 35 to 65 kts.

     Fiona continued moving west-southwestward as it strengthened. Perth
  upgraded the storm to severe tropical cyclone (hurricane) status at
  0400 UTC on 7 February when located approximately 125 nm southeast of
  Christmas Island. (At 1200 UTC JTWC also upgraded Fiona to hurricane
  intensity with 75-kt winds 1-min avg.) A 07/2320 UTC SSM/I pass depicted
  an eye embedded within partial concentric convective bands. Perth upped
  the intensity to 100 kts at 08/0400 UTC and to the peak intensity of
  105 kts at 1000 UTC. Gales reached outward 125 nm from the 16-nm
  diameter eye while the radius of 50-kt winds was estimated at 45 nm.
  The minimum CP estimated by Perth was 930 mb. At the time of its peak
  intensity, Fiona was located roughly 300 nm east-southeast of the Cocos
  Islands, moving west-southwestward at 10 kts. (JTWC's peak 1-min avg MSW
  for Fiona was 100 kts, somewhat less than the 120 kts implied by Perth's
  105-kt 10-min avg intensity.)

     By 09/0000 UTC Fiona was located about 260 nm southeast of Cocos,
  temporarily moving toward the southwest at 11 kts. Recent microwave
  imagery showed some drier air to the south of the cyclone. By 1000 UTC
  Perth had brought the intensity down to 90 kts (JTWC was still reporting
  100 kts 1-min avg MSW). Deep convection had weakened somewhat and the
  eye had become cloud-filled. Cooler air associated with a migratory
  high-pressure system was apparently affecting the system. Perth reduced
  the MSW to 80 kts at 09/1600 UTC where it remained pegged for over
  24 hours. Animated enhanced infrared and microwave imagery around 0000
  UTC on the 10th revealed that a 25-nm irregular eye had reformed, but
  animated water vapor imagery showed cooler and drier air beginning to
  wrap into the cyclone from the south. At 1200 UTC Fiona's center was
  located about 350 nm southwest of the Cocos Islands, moving westward
  at 8 kts.

     Fiona began to turn southwestward as it neared the 90th meridian.
  A deepening shortwave trough was forecast to weaken the subtropical ridge
  to the south of the cyclone. At 1000 UTC on 11 February Fiona was
  located approximately 500 nm southwest of Cocos, moving slowly south-
  westward with deep convection weakening. Perth's and JTWC's estimated
  MSW values at that hour were 75 and 80 kts, respectively. By 12/0400
  UTC Fiona had weakened to below hurricane intensity. The storm by this
  time was about 600 nm southwest of Cocos and moving due southward at
  around 8 kts. Tropical Cyclone Fiona recurved along the 91st meridian
  between 1600 and 2200 UTC on the 11th and thence began moving south-
  southeastward. The storm began to weaken rapidly as the 12th progressed,
  and by 13/0000 UTC had lost all its associated deep convection with
  the LLCC decoupling from the mid-level circulation. JTWC issued their
  final warning at 13/0000 UTC, and Perth followed suit with their final
  warning at 0400 UTC placing the center about 650 nm south-southwest of
  the Cocos Islands.

     According to an e-mail received from Carl Smith, much of the moisture
  from Fiona and Tropical Storm Isha west of 90E was sucked into a trough
  associated with a frontal system and transported east-southeastward.
  Fiona's remnant eventually passed south of southwestern Western Australia
  before recurving into the Great Australian Bight, and the residual LOW
  from Isha cut across the southwestern corner of the continent to meet
  it. The whole disorganized mess then moved northeastward overland
  through South Australia and New South Wales and up the coast into
  Queensland and the southern Coral Sea. All this influx of moisture
  could have been a factor in the formation of Tropical Cyclone Erica
  there in early March.

  C. Rainfall in Eastern Australia
  --------------------------------

     The Eyre Peninsula and Adelaide recorded more rain in 24 hours than
  they had in the previous two years. The New South Wales outback then
  experienced a good soaking, causing major flooding events in several
  towns, including Tamworth. The central New South Wales coast next
  experienced major flooding which closed the Pacific Highway, and finally
  the heavy rains reached the Gold Coast of Queensland. Carl stated that
  Stephens (where he lives) had had over 240 mm of rain within a 24-hour
  period. Over 100 houses along the Gold Coast were damaged due to the
  torrential rains and attendant flash flooding and landslips. (A special
  thanks to Carl for sending me the above information.)

  D. Damage and Casualties
  ------------------------

     There are no known casualties or damage resulting from the tropical
  cyclone stage of Fiona's life.

  (Report written by Gary Padgett)

                         TROPICAL CYCLONE GRAHAM
                                 (TC-20S)
                          26 February - 1 March
               -------------------------------------------

  A. Storm Origins
  ----------------

     JTWC issued a STWO at 0400 UTC on 23 February, noting that a
  persistent area of convection which had been located over land for the
  previous week had reached a position near the northwestern coast of
  Australia. A surface circulation was located approximately 210 nm east-
  northeast of Port Hedland. The LLCC was still over land, but the
  primary associated convection had moved over open water. A 200-mb
  analysis indicated that the disturbance was equatorward of a ridge axis
  under easterly vertical shear. The development potential was rated as
  fair, but was downgraded to poor on the 24th based on a less-organized
  appearance in satellite imagery.

     Around 2100 UTC on 25 February the LOW was located approximately
  160 nm north of Port Hedland. Animated visible imagery depicted sporadic
  weak convection in the vicinity, and a 25/0947 UTC QuikScat pass
  indicated a broad LLCC with the strongest winds on the equatorward side
  in a band along latitude 16S. The system was beneath moderate easterly
  vertical shear and the potential for development was still rated as poor.
  The Perth TCWC began issuing gale warnings on the LOW at 0100 UTC on the
  26th, the center of the LOW then being located about 225 nm north-
  northeast of Port Hedland. West to northwest winds of 35-40 kts were
  occurring in the monsoon trough well north of the center of the LOW.

     The system remained quasi-stationary on the 26th while slowly becoming
  better organized. JTWC issued a TCFA at 27/0230 UTC--animated visible
  imagery showed improving organization of the deep convection near the
  LLCC while QuikScat data revealed enhanced westerly winds equatorward of
  the LLCC. An upper-air analysis indicated that vertical shear had
  diminished while outflow remained good. At 0700 UTC on 27 February the
  Perth TCWC upgraded the LOW to Tropical Cyclone Graham with 45-kt winds
  (10-min avg), located approximately 200 nm northeast of Port Hedland.

  B. Track and Intensity History
  ------------------------------

     JTWC issued their first warning on Graham (TC-20S) at 1800 UTC on
  the 27th but only estimated the MSW (1-min avg) at 30 kts. The system
  was forecast to drift southeastward under the steering influence of a
  weak mid-level ridge to the north. By 0600 UTC on the 28th Graham's
  center was located about 180 nm northeast of Port Hedland, moving
  southeastward at only 3 kts. JTWC had upped the intensity to 35 kts
  while Perth had lowered their 10-min avg MSW estimate slightly to
  40 kts, although this was increased back to 45 kts six hours later.

     Tropical Cyclone Graham's center crossed the Western Australian
  coastline near the 80 Mile Beach at approximately 28/1400 UTC. Synoptic
  data in the vicinity indicated sustained winds of 38 kts (presumably
  a 10-min avg). By 1600 UTC the weakening Graham was inland about
  165 km south-southwest of Broome. The system continued to weaken and
  the final bulletin from Perth was issued at 0400 UTC on 1 March. JTWC
  likewise issued their final warning on Graham at 01/0600 UTC.

  C. Meteorological Observations
  ------------------------------

     The following table lists a few 24-hour rainfall totals associated
  with Graham which exceeded 100 mm:

  Station Period Amount
  --------------------------------------------------------------
  Derby 26 Feb/0100 UTC - 27 Feb/0100 UTC 157 mm
  Curtin RAAF 26 Feb/0100 UTC - 27 Feb/0100 UTC 148 mm
  Dampier Downs 27 Feb/0100 UTC - 28 Feb/0100 UTC 131 mm
  Shelamar 28 Feb/0100 UTC - 01 Mar/0100 UTC 142 mm
  Warrawagine 28 Feb/0100 UTC - 01 Mar/0100 UTC 115 mm
  Telfer 28 Feb/0100 UTC - 01 Mar/0100 UTC 175 mm

     The highest sustained wind observation apparently was SSE/45 kts from
  Mandora at 28 Feb/0200 UTC. Broome reported W/29 kts, gusting to 40 kts,
  at 01 Mar/0100 UTC. Port Hedland's highest wind was SSE/28 kts, gusting
  to 40 kts, at 01 Mar/0300 UTC, while West Roebuck recorded west winds of
  21 kts, gusting to 40 kts, at 28 Feb/1700 UTC. And finally, Telfer
  reported sustained winds of SE/38 kts, gusting to 48 kts, at 28 Feb/1800
  UTC. (A special thanks to Matthew Saxby for sending me the above
  observations.)

  D. Damage and Casualties
  ------------------------

     I have learned of no casualties or significant damage resulting from
  Tropical Cyclone Graham.

  (Report written by Gary Padgett)

  *************************************************************************

  NORTHEAST AUSTRALIA/CORAL SEA (AUE) - From 135E to 160E

  Activity for February: 1 tropical cyclone **
                          1 hybrid LOW

  ** - Remnants of Tropical Cyclone Beni from east of 160E briefly
       re-intensified off the Queensland coast in early February. Beni
       was covered in the January summary.

                      Northeast Australia/Coral Sea
                      Tropical Activity for February
                      ------------------------------

     As the month of February opened, the weak remnant LOW of former
  intense Tropical Cyclone Beni was moving westward across the southern
  Coral Sea. A band of gales of 40-45 kts began to develop well south
  of the center and the Brisbane TCWC began issuing gale warnings. Early
  on the 4th it appeared that the system might be turning into an intense,
  vertically-stacked hybrid just off the Queensland coast. So the system
  was re-upgraded to Tropical Cyclone Beni for a 12-hour period on
  4 February, but the vertical shear increased and proved to be too much
  for Beni to overcome and the low-level center became decoupled from the
  gales. The full history of Tropical Cyclone Beni, including its brief
  redevelopment in Australian waters, can be found in the January tropical
  cyclone summary.

     The only other system for which Brisbane issued warnings in February
  was a LOW which formed just off the Queensland coast near Townsville on
  the 26th. This system never developed any organized convective clouds
  near its center and was more of a hybrid LOW than a tropical system.
  Nonetheless, the system deepened some on the 28th, requiring the issuance
  of gale warnings. At 28/0000 UTC the LOW was centered approximately
  250 nm east of Rockhampton, moving south-southeastward. Gales of
  35-40 kts had developed by 1200 UTC and continued on into the early
  hours of 1 March. The final gale warning, issued at 0430 on 1 March,
  indicated that winds had dropped below gale force with the system then
  located about 300 nm east-northeast of Brisbane, still moving south-
  eastward.

  *************************************************************************

  SOUTH PACIFIC (SPA) - South Pacific Ocean East of Longitude 160E

  Activity for February: 2 tropical depressions **
                          1 tropical cyclone of hurricane intensity

  ** - One of these was not designated with the normal numbering system
       employed by Nadi for tropical depressions and may have been
       considered more of a hybrid or subtropical system.

                South Pacific Tropical Activity for February
                --------------------------------------------

     In contrast to January, when three tropical cyclones formed--two of
  them intense, February was much quieter with only one named cyclone.
  That system, Tropical Cyclone Dovi, became a very intense storm well
  east of the Dateline, but fortunately did not seriously affect any
  island communities. There were a few other systems which need to be
  mentioned, however. A long-lived weak system during the first week of
  February was designated as Tropical Depression 08F by the Nadi TCWC.
  The system was first identified as a tropical disturbance on 30 January
  when located about 200 nm north of American Samoa. The system remained
  quasi-stationary for a few days, but on 3 February was relocated several
  hundred miles to the south to a position about 175 nm east-southeast of
  Pago Pago, American Samoa. The LOW drifted slowly eastward for a couple
  of days, but on the 5th was relocated once more back to the west to a
  position just southwest of Samoa. Prior to this the system had been
  referred to as only a tropical disturbance, but at 05/0600 UTC Nadi
  upgraded it to tropical depression status. TD-08F subsequently moved
  slowly westward and by the 9th had weakened a couple hundred miles north
  of Fiji. Based on the Fiji Tropical Disturbance Summaries, sustained
  winds in this system likely did not exceed 15 kts.

     Another rather long-lived system was designated as Tropical
  Disturbance 10F by Fiji, but was never referred to as a tropical
  depression. This system was first identified well north of Fiji, west
  of Niulakita and north of Rotuma, on the 15th. The LOW drifted generally
  westward and was last mentioned on the 21st when located in the Solomon
  Island chain north of the Santa Cruz Islands. A final system referenced
  in the Nadi Tropical Disturbance Summaries formed on the 18th about
  350 nm east-northeast of Rarotonga in the Southern Cook Islands. This
  system was referred to simply as a LOW initially; then, beginning on
  20 February, was labeled Depression L1. Given its latitude (20S) and
  the unusual designation, it seems likely that this system was not a
  purely tropical LOW but more of a hybrid. The system moved southeast-
  ward and was last mentioned at 2100 UTC on the 21st when located about
  475 nm south-southeast of Tahiti. (Note: Tracks for Depression L1 and
  Tropical Depression 08F were included in the February cyclone tracks
  file, but not for Tropical Disturbance 10F.)

     The following report on intense Tropical Cyclone Dovi was written
  by Simon Clarke of Cleveland, Queensland. A special thanks to Simon
  for his assistance.

                         TROPICAL CYCLONE DOVI
                           (TD-09F / TC-15P)
                            5 - 12 February
               -----------------------------------------

  A. Storm Origins
  ----------------

     Dovi was the sixth tropical cyclone of the 2002/2003 South Pacific
  Tropical Cyclone Season and, following the trend set by Zoe and Beni,
  was to become yet another very intense storm. Tropical Cyclone Dovi
  was one of the most intense cyclones on record in the South Pacific
  east of the Dateline, exceeded in recent years only by Tropical Cyclone
  Ron in January, 1998.

     Dovi was first identified as a quasi-stationary circulation centre
  located within the South Pacific Convergence Zone in the vicinity of
  the Northern Cook Islands (approximately 460 nautical miles to the
  east-northeast of Pago Pago, American Samoa). At the time, the system
  was located in a favourable outflow environment to the east and north,
  with improving outflow elsewhere, weak to moderate vertical wind
  shear, and warm sea surface temperatures of approximately 30 C.

     The circulation initially moved to the southeast at about 8 knots
  while slowly showing signs of improved organization with convection
  increasing and cooling around the LLCC. Development of the system was
  to be fairly rapid, and at 2100 UTC on 5 February, Fiji upgraded the
  system to Tropical Depression 09F. The central pressure of the
  tropical depression quickly fell to 995 hPa, and within three hours
  TD-09F was upgraded to tropical cyclone status and named Dovi. At this
  time, the mid-level ridge to the east of the cyclone was steering the
  storm on a southerly path.

  B. Track and Intensity History
  ------------------------------

     The mid-level ridge ultimately pushed Dovi onto a south-
  southwesterly path which was sustained throughout much of its life.
  Initially, Dovi was underneath the 250-hPa ridge axis with relatively
  minimal shear and continuing high SSTs. With improving environmental
  conditions, Dovi continued to steadily intensify as it moved toward the
  southwest at approximately 8 knots. By late on 6 February the cyclone
  had reached hurricane status.

     Dovi continued to intensify at a fairly rapid rate as a 250-hPa
  anticyclone to the west moved closer to the cyclone. By 07/2007 UTC
  Dovi had developed a distinct eye. The peak intensity was reached
  at 08/1800 UTC with Dovi located near 19.4S, 167.8W, or approximately
  350 nautical miles south-southeast of Pago Pago. At this time Dovi's
  central pressure was estimated at 920 hPa and the storm was producing
  maximum 10-minute average winds of 110 knots close to its centre.
  (Editor's Note: JTWC's peak 1-minute average MSW for Dovi was
  130 knots--in good agreement with Nadi's estimate.)

     The demise of Dovi was to commence as a consequence of increasing
  vertical wind shear coupled with cooler SSTs. The storm was driven
  toward the south along the western edge of the poleward-oriented mid-
  level ridge and gradually lost its convective structure. By 1400 UTC
  on 10 February, the convective tops had become sheared to the south-
  east and the LLCC was displaced to the northwestern edge of the deep
  convection. Outflow in the western and southern quadrants remained
  good but was deteriorating elsewhere. Dovi had weakened to a 980 hPa
  storm by this time with maximum 10-minute average winds of 55 knots.
  Movement was to the south-southeast at 6 knots. Extratropical
  transition was complete by 11/0138 UTC with the storm near 26.0S,
  169.0W (or about 600 nautical miles southwest of Rarotonga). By this
  time, the ridge building to the south began to steer the remains of the
  storm slowly toward the south-southwest. The MetService based in
  Wellington, New Zealand, continued to issue warnings for the gales
  associated with the remnant of Dovi for a further 48 hours.

  C. Meteorological Observations
  ------------------------------

     I was almost ready to mail this summary when I received a report
  on Dovi from Alipate Waqaicelua, Chief Forecaster at the Nadi TCWC.
  There was not really anything new to include regarding the synoptic
  history of Tropical Cyclone Dovi, but Alipate's report did include
  one observation from Niue: "Niue only experienced strong winds (below
  gale) and very rough seas. There was neither structural damage nor
  loss of life. Damage to trees and vegetation was minor. The lowest
  pressure recorded was at 09/0125 UTC with 992.9 hPa. Maximum gust
  recorded was 35 knots at 08/2200 UTC and the maximum sustained wind
  was 21 knots at 08/2200 UTC." (A thanks to Alipate for sending the
  report.)

  D. Damage and Casualties
  ------------------------

     Tropical Cyclone Dovi spent its entire life at sea. Strong and
  gusty winds and heavy swells were reported from the Southern Cook
  Islands and Niue. Aside from damage to banana plantations on
  Palmerston Island, no significant damage was reported.

  (Report written by Simon Clarke)

  *************************************************************************

                               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 July, 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, and
  Chris Landsea):

    <http://australiasevereweather.com/cyclones/>
    <http://www.typhoon2000.ph> OR <http://64.235.42.210>
    <http://mpittweather.com>
    <ftp://ftp.aoml.noaa.gov/hrd/pub/landsea/padgett/>

     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>

                    TROPICAL CYCLONE REPORTS AVAILABLE

     JTWC now has available on its website the complete Annual Tropical
  Cyclone Report (ATCR) for 2001 (2000-2001 season for the Southern
  Hemisphere). ATCRs for earlier years are available also. Recently
  added was the report for the Southern Hemisphere 2001-2002 season.

     The URL is: <http://199.10.200.33/jtwc.html>

     Also, TPC/NHC has available on its webpage nice "technicolor"
  tracking charts for the 2002 Atlantic and Eastern North Pacific
  tropical cyclones; also, preliminary storm reports for all the 2002
  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

  John Wallace (Eastern North Pacific, North Indian Ocean, Western
                 Gulf of Mexico)
  E-mail: dosidicus@aol.com

  Kevin Boyle (Eastern Atlantic, Western Northwest Pacific, South
                China Sea)
  E-mail: newchapelobservatory@btinternet.com

  Simon Clarke (Northeast Australia/Coral Sea, South Pacific)
  E-mail: saclarke@iprimus.com.au

  *************************************************************************
  *************************************************************************

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