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Monthly Global Tropical Cyclone Summary January 2000
[Summaries and Track Data] [Prepared by Gary Padgett]


                               JANUARY, 2000

  (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 by the AUTHOR

     I have been cranking out these summaries now for slightly over two
  years, and from the beginning I have been overwhelmed by the reception
  they have gotten from the tropical cyclone community--not only from
  professional forecasters and researchers, but from those involved in
  catastrophe modelling, insurance risk studies, emergency management,
  etc, who have found material in the summaries useful to them, and also
  from those who just have a keen interest in studying and following
  tropical cyclones as a hobby.    The time involved, however, spent in
  constantly monitoring tropical cyclones, downloading warnings, and
  preparing and proofreading the summaries is quite substantial; and,
  considering that I have a long commute to work and am away from home
  twelve hours every day, the task of writing the summaries becomes very
  burdensome at times, especially during busy months.

     In an attempt to continue keeping the summaries coming in the form
  to which readers have become accustomed, I have enlisted the assistance
  of some fellows in various countries who, like myself, have studied and
  followed tropical cyclones for years and have a great interest in the
  storms.   A couple of guys, Matthew Saxby in Australia and Michael V.
  Padua in the Philippines, limit their work to sending me tracking
  information already typed in columnar format (which can require a
  substantial effort in some months).    Others, namely Patrick Hoareau
  in France, Carl Smith in Australia, and John Wallace in Texas have
  actually written some of the narratives for certain tropical cyclones
  in recent months.  Carl is currently writing reports for cyclones in
  the Australian Region, and Patrick plans to assist with the North
  Indian Ocean and at least some of the Northwest Pacific typhoons; and
  if time permits, John Wallace will write the narrative sections for
  Northeast Pacific tropical cyclones.  Also, it should be mentioned
  that Alipate Waqaicelua, Chief Forecaster of the Nadi, Fiji, Tropical
  Cyclone Warning Centre sends me summaries and tracks for most South
  Pacific tropical cyclones.  I am very grateful to all these gentlemen
  for their assistance (and also to many others who send me various
  bits and pieces of information about tropical cyclones and their

     That being said, it should be emphasized that I do carefully read
  their contributions and edit as I see fit.    Each one has his own
  writing style with emphases on particular things, and I want their
  individual personalities to shine through--in other words, I don't
  want to edit and revise to the point everything sounds as if I had
  written it.   But I do try to insure that there is some consistency 
  and that the basic things I've always covered remain.   No statement
  gets through into the final product that I personally object to.

     One other issue I'd like to address.   The Atlantic and Northeast
  Pacific basins are the only areas which essentially have only one
  major TCWC issuing advisories/warnings.   In all the other basins JTWC
  issues official warnings for the U. S. Military Services and for the
  benefit of any other parties who wish to use them.  Also, with the
  exception of the Australian Region, in the other basins there are
  national meteorological services which issue warnings in addition to
  the official RSMC and JTWC.        From the beginning I have made
  occasional comparisons between warnings from different warning agencies
  when there were significant differences in position and/or intensity.
  Analysis of tropical cyclone center positions and intensity by remote
  sensing (satellite imagery) is often difficult and very subjective.
  It is far from being an exact science.    But I have always tried to
  be objective in pointing out these to-be-expected discrepancies such
  that there is no implied criticism of one TCWC over another, and this
  rule likewise applies to any narratives written by my assistants.

                           JANUARY HIGHLIGHTS

  --> Intense cyclone threatens Southwest Indian Ocean islands
  --> South Pacific sees first cyclones of season

                           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:  No tropical cyclones

  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
                         1 tropical depression (from December)
                         1 tropical cyclone
                         1 intense tropical cyclone

     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.
  Also, the comments about satellite imagery and other sources of data
  such as SSM/I and TRMM were obtained for the most part from the JTWC
  warnings.     A special thanks to Philippe Caroff of the La Reunion
  TCWC for sending me information on the tropical disturbance #03, and
  a special thanks to Patrick Hoareau and Jean Marc de Maroussem for
  passing along some observations from Mauritius and Reunion during
  the approach of Tropical Cyclone Connie.

                  South Indian Ocean Activity for January

     After getting off to a rather late start (in late December), the
  tropical cyclone season in the South Indian Ocean became significantly
  more active during the month of January.    Babiola became the first
  actual tropical cyclone (hurricane force) in the region, and Connie
  became an intense tropical cyclone and threatened the islands of
  Mauritius and La Reunion.   As the month opened, Tropical Depression
  Astride (formerly a tropical storm) was still present in the
  Mozambique Channel.  (See the December summary for a full report on
  Tropical Storm Astride.)

     In addition to Babiola and Connie, disturbed weather persisted in
  the Mozambique Channel for a couple of weeks starting just before
  mid-month.  Meteo France on Reunion Island (MFR) issued a couple of 
  bulletins on this system on 12 and 13 Jan, numbering it as disturbance
  #03.  JTWC mentioned the area in its STWOs for a few days, but dropped 
  it on 16 Jan.  Beginning on 22 Jan JTWC once again began mentioning an
  area of convection in the Channel with an associated partially-exposed
  LLCC.   MFR issued a single bulletin at 0600 UTC on 24 Jan, referring
  to the disturbance as #03 once more, so apparently there was possibly
  some connection between this flare-up and the earlier disturbance.
  JTWC continued to monitor the disturbance through 26 Jan when it had
  weakened significantly.  I have attempted to piece together a track
  for this system in the companion tracks file.

     Finally, a new disturbance/depression formed at the end of the month
  and was christened Tropical Storm Damienne on 1 Feb.  A report on the
  short-lived Damienne will be included in the February summary.

                Tropical Cyclone Babiola  (TC-04S / SIO #02)
                               3 - 12 January

     A STWO issued by JTWC on 1 Jan indicated that an area of convection
  with an associated very weak LLCC had formed approximately 130 nm
  south-southeast of Diego Garcia.   Over the next couple of days the
  disturbed area drifted eastward and by 3 Jan was located about 650 nm
  east-southeast of Diego Garcia.   MFR began issuing bulletins on the
  developing disturbance at 0600 UTC.      Animated visible satellite
  imagery and scatterometer data indicated weak vertical shearing over
  the disturbance and animated water vapor imagery indicated fair
  outflow.  JTWC issued the first of three Formation Alerts at 1630 UTC,
  noting that there had been a significant increase in the areal coverage
  of convection.   SSM/I data revealed deep convection developing around
  the eastern and southern sides of the LLCC.

     JTWC issued a second Formation Alert at 04/1430 UTC and a third one
  on 5 Jan at 1430 UTC.  The disturbance had continued to drift slowly
  eastward (or quite possibly a new center had formed) during this time.
  The first JTWC warning, issued at 05/1800 UTC, placed the center of
  the system almost 700 nm east-southeast of Diego Garcia and moving
  southwestward at 9 kts.  The MSW (1-min) was estimated at 35 kts, and
  convection was consolidating around the LLCC.  The system was forecast
  to track southwestward under the influence of a low- to mid-level
  subtropical ridge to the south-southeast.  MFR upgraded the developing
  LOW to a tropical depression six hours later with 30-kt winds (10-min
  avg), and Moderate Tropical Storm Babiola was christened at 0600 UTC
  on 6 Jan, located about 625 nm east-southeast of Diego Garcia.  At
  1800 UTC Babiola's intensity was holding steady at 35 kts (45-kts 1-min
  avg from JTWC) with the LLCC displaced somewhat to the east-southeast
  of the primary convection.

     On 7 Jan Babiola continued to move slowly to the southwest and
  steadily increased in intensity.  MSW estimates from both MFR and JTWC
  had reached 55 kts by 1800 UTC.  A TRMM pass indicated a significant
  convective band extending southeast through north wrapping in toward
  the LLCC with animated infrared imagery depicting another band forming
  180 nm to the west of the LLCC.    Babiola began to accelerate toward
  the west-southwest on the 8th and continued to intensify, reaching
  cyclone (hurricane) strength at 1200 UTC when centered about 575 nm
  south of Diego Garcia.  A banding eye became apparent, and Babiola
  presented a rather symmetrical appearance in satellite imagery with
  an upper-level HIGH over the storm enhancing outflow in all quadrants.

     The west-southwestward to southwestward motion continued through
  9 Jan with Babiola reaching its peak intensity late on the 9th. 200-mb
  analysis showed that the cyclonic circulation extended into the upper
  levels with good outflow.  At 1800 UTC Babiola displayed a ragged eye
  20 nm in diameter with good outflow channels over the western half of
  the system.  The cyclone was by this time beginning to move south-
  southwestward.    JTWC's peak MSW (1-min) of 90 kts was reached at
  this time, and MFR had upgraded Babiola to its peak intensity of
  80 kts at 1200 UTC.  This represents a perfect agreement of Babiola's
  peak intensity between the two TCWCs, corresponding to a Dvorak scale
  rating of T5.0.   The minimum CP estimated by MFR was 954 mb.

     On 10 Jan Babiola remained intense but began to show signs of
  weakening.  The storm began to move due southward and reached the
  westernmost point of its trajectory around 1200 UTC when it was located
  about 250 nm east-southeast of Rodrigues Island (which lies about
  315 nm east of Mauritius).   Early in the day the eye disappeared and
  Babiola began to elongate and merge with a trough moving rapidly
  across the South Indian Ocean.  By 1800 UTC the storm was tracking
  south-southeastward and the MSW was down to 70 kts (65 kts per JTWC).
  Babiola was becoming less organized due to northwesterly shear.

     The storm continued to weaken on 11 Jan as it continued toward the
  south-southeast and experienced strong vertical shear.  By 0600 UTC
  Babiola was merging with the approaching trough and beginning extra-
  tropical transition (this based upon remarks in the 0600 UTC JTWC
  warning).    Animated satellite imagery and data from a SSM/I pass
  showed an exposed LLCC with convection sheared 85 nm to the south
  and east.   JTWC issued its last warning on Babiola at 0600 UTC on
  12 Jan with winds estimated at only 25 kts, but MFR continued gale
  warnings for the weakening system through 12/1200 UTC, although the 
  bulletins indicated that the gales were forecast to be occurring well
  away from the center (up to 120 nm) in the southeast quadrant.  Early
  on the 12th the previously mentioned 500-mb trough was just west of 
  Babiola and was interacting with the system, which was becoming 
  extratropical.   MFR issued their last bulletin on Babiola at 1800 UTC,
  downgrading the system to below gale intensity and locating the center
  approximately 800 nm southeast of Rodrigues Island.

                Tropical Cyclone Connie  (TC-08S / SIO #04)
                          25 January - 2 February

     An area of convection appeared on 24 Jan about 315 nm east of
  northern Madagascar.  SSM/I data indicated a fully-exposed LLCC with
  disorganized convection.  The next day the persistent convection had
  become more organized and MFR initiated Tropical Disturbance Bulletins
  at 0600 UTC for disturbance #04.  The rapidly strengthening disturbance
  was upgraded to a tropical depression six hours later and to Moderate
  Tropical Storm Connie at 1800 UTC with 40-kt winds.     Connie was
  centered about 325 nm northwest of Mauritius at that time.   (JTWC
  issued a Formation Alert at 1000 UTC, and their first warning was
  issued at 1800 UTC, giving a MSW estimate  of 35 kts (1-min).)
  Convective organization was increasing in an environment of good
  outflow and weak vertical shear.  TRMM microwave imagery depicted
  banding of deep convection in the northeast through southwest
  quadrants.   The storm had been quasi-stationary for several hours
  but was forecast to track southwestward under the influence of a
  mid-level ridge to the south.

     Connie, however, remained more or less stationary, and actually
  moved (or was relocated) northward a bit on 26 Jan while slowly
  strengthening.  A TRMM pass at 26/0703 UTC revealed what appeared to
  be a 27-nm wide eye.  At 1800 UTC Connie's intensity had reached
  45 kts (55 kts 1-min avg from JTWC) and was still quasi-stationary
  about 380 nm north-northwest of Mauritius.   By 0600 UTC on 27 Jan
  the by-now severe tropical storm with 60-kt winds was moving south-
  eastward at 6 kts.  A SSM/I pass at 0141 UTC revealed an irregular
  eye 20 nm in diameter with the eyewall surrounding approximately
  4/5 of the vortex.     Multi-spectral imagery showed a significant
  convective band entering the LLCC from the southern half of the

     At 1200 UTC Connie's center was about 300 nm north-northwest of
  Mauritius and MFR upgraded the storm to cyclone status with 80-kt
  MSW.  (JTWC's concurrent 1-min avg MSW was 85 kts at the time.)
  The eye diameter by this time had shrunk to 11 nm and convective
  features were continuing to develop and build in toward the LLCC
  from the southeast and northeast.  With an upper-level HIGH located
  over the cyclone, the outflow continued to improve and Connie began
  to strengthen rapidly.  By 1800 UTC Connie's well-defined 15-nm wide
  eye was located approximately 235 nm northwest of Mauritius and had
  moved south at 7 kts over the previous six hours.     There was a
  surface synoptic report of 10-min avg winds of 31 kts from WMO 61986,
  located about 140 nm due east of the cyclone.

     Throughout Connie's life center position estimates between JTWC
  and MFR were in excellent agreement, and intensity estimates agreed
  fairly well except that on 28 and 29 Jan, when the cyclone was at
  its peak, there was some divergence of opinion regarding the cyclone's
  intensity.   At 27/1800 UTC JTWC increased the MSW (1-min) to 115 kts,
  which equates to T6.0 on the Dvorak scale.  MFR's 10-min MSW estimate
  was 90 kts--equivalent to a Dvorak rating of T5.5--and as everyone
  in the business knows, a difference in Dvorak analysis of 0.5 T-number
  represents good agreement.   At 28/0600 UTC JTWC began to gradually
  bring down Connie's MSW while MFR's value held steady at 90 kts.
  At 1800 UTC Reunion increased its MSW estimate to a peak of 100 kts
  (T6.0 on the Dvorak scale) while JTWC had brought its value down to
  105 kts (T5.5).      Remarks in the JTWC warning indicated that this
  was based upon CI estimates of 102 kts and 127 kts (T5.5 and T6.5).
  Connie's eye had remained well-defined, but cloud tops had warmed
  somewhat over the cyclone's center.       MFR maintained the 100-kt
  intensity through 29/0600 UTC and then brought the MSW down to 85 kts
  at 29/1200 UTC.  JTWC's estimates had continued to slowly decline and
  had reached 80 kts (1-min) by 1200 UTC.   The minimum CP in Connie's
  history as estimated by MFR was 928 mb at 28/1800 UTC.
     By 0000 UTC on the 29th Connie was centered about 130 nm northwest
  of Mauritius.  The cyclone was maintaining a 10-nm diameter eye, but
  was showing signs of shearing to the south.     Water vapor imagery
  indicated a weak TUTT to the southwest of the storm which was causing
  the increase in vertical shear.    By 1800 UTC on 28 Jan Connie was
  moving to the southwest on a track which carried it about 100 nm west
  of Reunion Island around 1800 UTC on 29 Jan.   The MSW was down to
  80 kts (both MFR and JTWC) as the eye was no longer apparent and drier
  air from the TUTT was being injected into the storm's inflow.   At
  30/0000 UTC Connie was located approximately 145 nm west-southwest of
  Reunion and moving southwest at 11 kts--a motion which had increased
  to 18 kts by 0600 UTC.  The storm's intensity was down to near minimal
  cyclone force by this time, and Connie was beginning to recurve to the

     By 1800 UTC on 30 Jan the storm was moving southward about 265 nm
  east of the southern tip of Madagascar with 55-kt winds (60 kts 1-min
  avg from JTWC).  Earlier in the day a SSM/I pass had indicated a spiral
  band of convection to the west of the LLCC, but a TRMM pass at 1331 UTC
  indicated only isolated convection to the south of the center and
  Connie was forecast to continue weakening.   On 31 Jan Connie began to
  move in a southeasterly direction, steered by a mid-level subtropical
  ridge to the northeast and the approaching trough to the southwest.
  The storm, however, held on to its intensity with the MSW remaining
  at 55 kts through most of the day.  JTWC actually increased its 1-min
  avg MSW to 65 kts briefly at 1800 UTC based upon satellite intensity
     However, any re-intensification was short-lived.   Animated visible
  imagery early on 1 Feb showed a fully-exposed LLCC with rapidly
  weakening convection about 70 nm to the east of the center.  Infrared
  imagery depicted a rapid warming of cloud tops as well as a significant
  decrease in the areal extent of deep convection.   MFR issued its final
  warning at 01/0000 UTC since Connie appeared to be rapidly losing
  strength and was taking on extratropical characteristics.    JTWC
  continued to track the rapidly weakening storm through 0600 UTC on
  2 Feb when the MSW was estimated at only 25 kts and the center was
  located about 725 nm south of Reunion Island.  SSM/I data indicated
  a fully-exposed LLCC with weakening convection displaced about 75 nm
  northeast of the center.  The remnants of Connie were forecast to
  continue moving southeastward and weaken.

     Jean Marc de Maroussem, a resident of Mauritius, sent me some
  observations he'd made during Connie's closest approach to the island.
  The lowest pressure reported by Jean Marc was 1000.6 with several wind
  gusts exceeding 55 kts and a peak gust of 65 kts.     The average
  rainfall for the entire island was about 200 mm--a bit of relief for
  the drought-stricken island but not enough.

     As far as Reunion Island goes, Patrick Hoareau reported that he'd
  been listening to the official radio on the internet and wind gusts
  of around 60-80 kts had been reported.     Also 16,000 people were
  without power.   Press reports indicated that Connie was responsible
  for two deaths on Reunion.       One hundred homes were reportedly
  destroyed with at least 600 persons homeless.


  AUSTRALIAN REGION (AUG) - From Longitude 90E Eastward to Longitude 160E

  Activity for January:  2 tropical LOWs
                         1 hybrid LOW
                         1 severe tropical cyclone

     The primary sources of information for Australian Region tropical
  cyclones are the warnings and bulletins issued by the three TCWCs
  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.  References
  to sustained winds should be understood as being based on a 10-min 
  averaging period unless otherwise noted.
    Matthew Saxby, a tropical cyclone enthusiast from Queanbeyan, New
  South Wales, Australia, typed up the tracks for the cyclones and LOWs
  in the Australian Region.  Also, Carl Smith, another dedicated tropical
  cyclone enthusiast from the Gold Coast of Queensland, authored the
  narratives for Tropical Cyclones 06S and Kirrily.   A very special
  thanks to Matthew and Carl for their assistance.

  A description of the Australian Cyclone Severity Scale can be found in
  Chris Landsea's FAQ on HRD's website:>

  or on Michael Bath's Australian Severe Weather site:>

  Also, I performed some editing on Carl's write-ups.   For anyone who is
  interested in reading his complete cyclone reports, they are available
  at the following URLs:>>

                  Australian Region Activity for January

     Tropical cyclone activity in the Australian Region was somewhat on
  the quiet side.  Only one cyclone--Kirrily--was named, and this was
  late in the month in the Southeast Indian Ocean off Western Australia.
  Earlier there was a tropical LOW in the same region which persisted for
  several days and eventually made landfall in Western Australia.  JTWC
  issued one warning of 35-kt winds with this system based upon a ship
  report.   Since Carl submitted a report on this LOW, I have included
  it below.

     There was a short-lived tropical LOW in the Coral Sea off the coast
  of Queensland for which Brisbane issued a few warnings on 10 and 11
  Jan.  Gale-force winds to 35 kts were forecast for the southern
  quadrant of the LOW at one point.  There was also a gale center on 12
  and 13 Jan well east of Brisbane which moved slowly westward toward
  the southern Queensland coast.  This system was likely a hybrid or
  primarily baroclinic LOW.   Tracks are given for these two systems in
  the companion cyclone tracks file.

     Additionally, there was an interesting example of a so-called
  "landphoon"--a tropical LOW whose convective cloud signature seems to
  improve even after it has moved over land.  In mid-January a very weak
  LOW formed near the coast of Western Australia and tracked southward
  and inland.  The maximum winds and minimum pressure when the system
  was just off the coast were about 15-20 kts and 999 mb, respectively.
  The cloud signature seemed to improve somewhat as the LOW moved
  further inland over the Australian Outback.  On Sunday, 16 Jan the
  center passed just west of the Giles Meteorological Station (25.0 S,
  128.3 E) and radar showed the circulation to be very weak.

     Australia is one of the very few places where weak tropical LOWs
  can drift inland and "appear" to intensify, even after they have
  travelled well inland for a day or two.  From a satellite perspective
  these systems look like tropical storms, with persistent central
  convection and a nice symmetrical pattern of cirrus outflow.  It is
  very possible that in the middle troposphere the circulation does
  indeed intensify somewhat.   From the standpoint of process, it seems
  as if atmospheric conditions are extremely favorable for tropical
  cyclone formation, and they do the best they can with land underneath.

     (The above discussion was taken from some correspondence with Mark
  Lander of the University of Guam and Andrew Tupper of BoM, Darwin.)

                         Tropical LOW  (TC-06S)
                             18 - 23 January

     During the 3rd week of January, 2000, a tropical LOW formed in the
  Gulf of Carpentaria, northwest of Weipa on Cape York Peninsula.   It
  drifted slowly west-northwestward into the Arafura Sea over the next 
  few days, passing to the north of Arnhem Land and Darwin.
     By the 18th it had moved into the Timor Sea.  BoM Darwin issued the
  first shipping warning at 1200 UTC, indicating that a tropical LOW of
  1000 mb was centred within 90 nm of 11.0 S, 127.5 E and moving west at
  5 kts.   Darwin continued issuing shipping warnings until 19/1200 UTC
  when responsibility was handed over to BoM Perth as the system was by
  then off the Kimberley Coast near 12.7 S, 125.3 E, moving southwest
  at 10 kts.

     Over the next couple of days the LOW continued moving southwestward
  towards the Pilbara coast.   JTWC issued the first TCFA on the 20th; 
  however, development was generally slower than either JTWC or Perth
  expected, with JTWC issuing another TCFA later in the day.
     Perth issued the first Tropical Cyclone Advice at 6:50am WST on the
  21st (20/2250 UTC), stating that at 6:00am a tropical LOW was located
  about 380 km (205 nm) north-northeast of Karratha and moving southwest
  at 15 kts.   The first cyclone warning was issued by JTWC at 21/0300
  UTC, indicating that TC-06S had developed in the southeast Indian Ocean
  about 350 nm northeast of Learmonth and was tracking southwestward at
  10 kts within the steering flow of a subtropical ridge to the

     The 1st BoM warning for coastal communities was issued at 3:50pm
  WST (0750 UTC) on the 21st for areas between Roebourne and Exmouth.
  At 3:00pm (0700 UTC) the LOW with a CP of 1000 mb was estimated to be
  about 290 km (155 nm) north-northwest of Karratha and moving south-
  southwestward at 10 kts.     At 21/0900 UTC JTWC noted that animated
  satellite imagery indicated a rapid weakening of TC-06S, and animated
  water vapour imagery revealed increasing vertical wind shear to the
  southeast due to a mid-latitude trough and associated support of a
  strong upper-level jet.

     The difficulties JTWC had in tracking this marginal tropical cyclone
  were revealed when it was relocated 60 nm to the east-northeast of the
  previous warning position at 21/2100 UTC.   The warning noted that the
  system displayed a fully exposed LLCC with deep convection to the
  southwest (based on DMSP night-time visible imagery), and animated
  infrared satellite imagery depicted increasing convection over the
  previous six hours.

     Over the subsequent 24 hours TC-06S continued its west-southwestward
  motion towards the Pilbara Coast, slowly deepening to 992 mb, but never
  quite reaching tropical cyclone strength according to BoM criteria.
  The only significant change was noted in a JTWC warning issued at
  22/1500 UTC, which stated that, based on infrared satellite imagery,
  the system had taken a turn to the southeast during the previous six
  hours, and it appeared that the low/mid-level HIGH over the Western
  Plateau had weakened and shifted further east than model guidance had
  previously indicated, due primarily to the sudden eastward movement of
  a mid-latitude trough which had been quasi-stationary off the southwest
  coast of Australia.     Water vapour imagery also indicated that the
  trough had increased in amplitude.

     The BoM issued its final warning on this system at 9:50am WST
  (23/0150 UTC) on the 23rd, stating that the tropical LOW with a CP of
  992 mb and wind gusts to 40 kts was, at 9:00am WST, estimated to be
  about 70 km (40 nm) west-northwest of Port Hedland, moving south-
  eastward at 14 kts.   JTWC issued its final warning at 23/0300 UTC,
  noting that the system was dissipating over land.

  NOTE:  JTWC only issued one warning (22/0600 UTC) estimating the 1-min
  avg MSW at 35 kts.  Satellite intensity estimates were 25 kts, but the
  remarks indicated that there was a synoptic ship report of 35-kt winds
  west of the center.

                 Severe Tropical Cyclone Kirrily  (TC-09S)
                          25 January - 1 February

     A developing 1002-mb tropical LOW in the Indian Ocean southeast of
  Christmas Island was first mentioned in an Australian Bureau of
  Meteorology (BoM), Perth, shipping warning issued at 2157 UTC on
  25 Jan when the LOW was centered about 250 nm southeast of Christmas
  Island, moving east-southeastward at 11 kts.  JTWC issued a Tropical
  Cyclone Formation Alert (TCFA) at 26/2130 UTC with winds estimated to
  be 25-30 kts.  Satellite imagery at 1730 UTC indicated that a LLCC
  was located about 400 nm north-northwest of Exmouth, Western Australia,
  moving southeastward at 10 kts.  Scatterometer data indicated a well-
  defined LLCC associated with the convection and 200-mb analysis
  indicated that the convection was slowly moving under the axis of an
  upper-level ridge which would be expected to provide good outflow.
  University of Wisconsin CIMSS Wind Shear charts also indicated
  decreasing vertical shear in the path of the disturbance in the
  direction of northwestern Australia.

     The first tropical cyclone warning was issued by JTWC for TC-09S
  at 27/0900 UTC.  MSW (1-min) were estimated at 30 kts and the centre
  was placed about 330 nm north-northwest of Learmonth, Western
  Australia, moving south at 5 kts.  Animated multi-spectral imagery
  depicted new convection building over the LLCC and low-level cloud
  lines were visible moving in toward the center from the southeast.
  A mid-level HIGH situated over southwestern Western Australia was
  forecast to build northwestward over the Kimberley region within
  36 hours and should cause TC-09S to track initially south-
  southeastward, then southwestward.

     The LOW was named Kirrily by BoM Perth at 28/0016 UTC.  The CP was
  given as 985 mb and the 0000 UTC position was about 300 nm northwest
  of Exmouth.  Kirrily was moving southwestward at 6 kts and was causing
  rough to very rough seas with moderate swell and 30-40 kt winds within
  100 nm of the centre and winds to 50 kts within 30 nm of the centre.
  The first public Tropical Cyclone Update was issued by Perth at 8:45am
  WST (0045 UTC) on Friday, 28 Jan, stating that Kirrily, a Category 1
  cyclone, was located about 295 nm northwest of Exmouth.

     At 28/0600 UTC JTWC placed Kirrily's center about 325 nm northwest
  of Exmouth, moving west at 9 kts with 55-kt winds (1-min avg).  A TRMM
  pass at 0314 UTC indicated that the system was developing an eye and
  that convective banding was surrounding about 8/10 of the vortex. BoM
  TC Update #2 at 2:30pm WST (0630 UTC) upgraded Kirrily to a
  Category 2 cyclone that was moving southwestward at 6 kts.  Only one
  more public update was issued since it had become clear that Kirrily
  posed no real threat to the Western Australian coastline.

     At 29/0600 UTC JTWC placed Kirrily's center about 600 nm south-
  southeast of Christmas Island, moving southwestward at 10 kts with
  MSW (1-min) of 80 kts and sporting a 13-nm wide cloud-filled eye.  A
  minimum CP of 965 mb was estimated by Perth at 1100 UTC when Kirrily
  was located approximately 625 nm south-southeast of Christmas Island.
  The BoM warning indicated that winds to 65 kts were likely occurring
  within 30 nm of Kirrily's centre.

     By 1800 UTC JTWC had decreased its MSW estimate to 70 kts as the
  cyclone continued to move to the southwest at 9 kts.  Kirrily at this
  time was located about 675 nm south of Christmas Island or about
  470 nm west of Learmonth.   Animated satellite imagery showed weakening
  of the system and elongation to the southeast.  A 29/1404 UTC SSM/I
  pass indicated a very bload LLCC; however, convection was confined to
  the very center and there was no longer any evidence of any type of
  eye.  A 200-mb analysis indicated that the upper-level ridge axis
  remained south of the system and an upper-level jet was evident to the
  southeast.  Kirrily was tracking west-southwestward under the steering
  influence of a mid-level subtropical ridge to the south and was moving
  into an environment of increasing vertical shear.

     Subsequent warnings issued by both centres indicated a continued
  weakening trend, with the final BoM shipping warning being issued at
  2225 UTC on 31 Jan.      The weakening remnants of Tropical Cyclone
  Kirrily with a CP of 999 mb were located about 750 nm south of
  Christmas Island at 2200 UTC and were moving north-northwestward at
  4 kts.  Winds were forecast to ease below gale force within the next
  three to six hours.  The last warning was issued by JTWC at 2100 UTC
  on 1 Feb with the MSW (1-min) estimated to be only 25 kts.  Infrared
  satellite imagery indicated a fully exposed LLCC which was moving
  northwestward at 6 kts.  The final JTWC warning placed the dissipating
  centre about 625 nm west of Learmonth or about 700 nm south-southwest
  of Christmas Island.


  SOUTHWEST PACIFIC (SWP) - South Pacific Ocean East of Longitude 160E

  Activity for January:  2 tropical depressions
                         2 tropical cyclones of storm intensity

     Most of the information presented below was taken from the
  operational warnings and advisories issued by the Fiji TCWC at Nadi.  
  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.  Last season Fiji 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.

     The reports on Tropical Cyclones Iris and Jo were written by
  Alipate Waqaicelua, Chief Forecaster at the Nadi TCWC, with only
  minimal editing by myself.  A very special thanks to Alipate for
  sending me the summaries and the cyclone tracks.   I wrote the
  discussion on Tropical Depression 08F; also, I added some discussion
  about the extreme Dvorak objective T-numbers generated for Tropical
  Cyclone Iris.

                  Southwest Pacific Activity for January

     January saw the formation of the first two South Pacific tropical
  cyclones of the 1999-2000 season.    In addition to Tropical Cyclones
  Iris and Jo, there were a couple of systems carried in warnings from
  Fiji as tropical depressions.   One of these, TD-08F, persisted for
  several days with associated gale-force winds, so I have included a
  separate report on this system below.    Another depression, TD-06F,
  formed on 3 Jan near Vanuatu and moved slowly east-southeastward over
  the next couple of days.   The system formed and operated in a sheared
  environment which did not allow it to strengthen.     The depression
  passed south of Fiji and had weakened just east of the Dateline by
  6 Jan.   A track is included for this system in the companion cyclone
  tracks file.  (A tropical disturbance numbered 07F was mentioned in
  Nadi's Tropical Disturbance Summary on 16 Jan, located well to the
  west-southwest of Tahiti.  This disturbance subsequently dissipated
  without being accorded depression status.)

                  Tropical Cyclone Iris  (TC-05P / TC-05F)
                              7 - 10 January

     A disturbance was first identified around 03/0600 UTC just north-
  west of Espiritu Santo, in Vanuatu, embedded in a stationary monsoon
  trough. The system was located under a moderately sheared environment
  aloft, with slightly hostile conditions at lower levels.    This 
  basically denied the system any chances for further development.
     For another 36 hours, the system was subjected to shear and diurnal
  influence, making it at times extremely difficult to locate the general
  centre.    However, after 06/0000 UTC, the outflow around the system 
  improved significantly with convection increasing and getting slightly
  more organised.   Twenty-four hours later, at 07/0000 UTC, convection  
  was getting better organised still, with the LLCC gradualy moving under
  the western edge of the deep convection.    Gale warnings were issued 
  but for certain sectors only.    Overnight the depression, displaying
  midget characteristics, intensified further under weakening shear   
  aloft.  A compact CDO had also formed which was now moving southeast
  at 5 kts.

     The depression continued to develop under favourable conditions, and
  at 07/2100 UTC was named Tropical Cyclone Iris while located about
  180 nm northwest of Port Vila, moving southeast at 5 kts with an
  intensity of 35 kts (10-min avg) and forecast to increase to 40 kts
  during the next 6 to 12 hours.   The cyclone was anticipated to track  
  more easterly under a westerly steering current.   Six hours later, at
  08/0000 UTC, winds around the compact centre were estimated to be about
  45 kts.    Gales were confined to within 60 nm of the centre.   Iris
  reached storm intensity at 08/0600 UTC while located about 130 nm
  northwest of Port Vila, tracking east-southeastward at 8 kts.  The
  cyclone moved close to or over the island of Epi overnight, but its 
  compactness was quite evident as recorded winds over Vila, about 60 nm 
  due south, were only 15 to 20 kts.    No damage reports could be
  obtained from Vanuatu, but it is most likely that damage, if any, 
  would be minimal.  This was despite an intensity of 60 kts at its
  peak, which occurred around 08/1200 UTC.

     Iris gradually accelerated eastward as it left Vanuatu, but always
  tracking more and more south of east with time.  The system was also
  becoming more and more asymmetric as it moved closer to Fiji, evidence
  of strengthening shear and environmental influence.  After 09/0000 UTC,
  the cyclone began its weakening trend.   Intensity was down to a gale
  18 hours later, at 09/1800 UTC, when it was located about 210 nm west-
  southwest of Nadi and moving east-southeastward at 13 kts.     After
  10/0000 UTC, while only about 120 nm southwest of Nadi, Iris was 
  shunting east-southeastward at 15 to 20 kts into increasing shear
  and cooler waters. The cyclone was downgraded to a depression 48 hours
  after it had reached its peak intensity--the final warning placing
  the centre on the Dateline about 150 nm southeast of Fiji.
     Though it was expected that as the system weakened gales might
  expand further out from the centre, only fresh to strong winds and very
  rough seas with heavy swells were experienced over the western and 
  southern parts of Fiji. Once the system was named, the intensity curve
  took a rate much steeper than any 'normal' cyclone.  This was also the
  case during the decay phase, though at a much gentler trend.   Damage
  in Fiji, if any, would have been either minimal or negligible.

     JTWC's positions and 1-min avg MSW estimates agreed very well with
  Nadi's for Tropical Cyclone Iris.    The peak MSW (1-min) from JTWC
  was 65 kts while the peak 10-min avg MSW estimated by Nadi was 60 kts.
  However, Iris exhibited some features which hinted that the midget
  cyclone could have been far more intense for a brief time than either
  warning centre estimated.   According to Dr. Mark Lander, T-numbers
  obtained with the objective (digital) Dvorak method reached T6.5 or
  slightly higher for a 4-hour period on 8 Jan from around 0230 to 0630
  UTC.  The Dvorak scale equates T6.5 with a MSW (1-min) of 127 kts or
  a 10-min avg MSW of 112 kts.      A satellite bulletin from JTWC at
  08/0625 UTC assigned a T-number of 4.0, but the comments indicated
  that there was a great inconsistency between the visible and infrared
  methods with an IR-derived T-number of 6.0.   These extreme T-numbers
  persisted for only a short time, however.   By 0915 UTC the eye had
  disappeared and a JTWC satellite bulletin indicated that the system
  had lost much convection over the past two hours.

     Mark Lander further comments that such rapid strengthening followed
  by rapid decay seems to be a common occurrence with very small, midget
  tropical cyclones.   They seem unable to remain at peak intensity for
  very long--often for just a few hours--before beginning to fall apart.
  Typhoons Ellie (1991) and Virgil (1999) were two recent NWP systems
  which behaved the same way as Iris.  No one will ever know just how
  intense Iris became since the core of the small cyclone did not pass
  over any weather station and of course there was no aerial
  reconnaissance available.

                       Tropical Depression  (TD-08F)
                              20 - 26 January

      A tropical disturbance was noted near Apia, Western Samoa, around
  0600 UTC on 20 Jan.  Over the next few days the system drifted slowly
  southwestward and gradually became better organized.  By 23/1800 UTC
  the disturbance had become sufficently developed to be classed as a
  tropical depression with the Fiji TCWC initiating gale warnings and
  Tropical Disturbance Advisories.   TD-08F was then located between
  Fiji and the Kingdom of Tonga and displayed a CDO-type cloud pattern.
  However, the system had moved south of the 250-mb subtropical ridge
  and was being affected by increasing westerly and northwesterly shear.

     The depression recurved to a southeasterly course and passed through
  the southern Tongan islands on 24 Jan.  At 24/0600 UTC the LLCC was
  still exposed and the gale-force winds were confined to the south-
  eastern semicircle.  Six hours later the LLCC had moved closer to the
  CDO feature and the cold cloud tops had increased in areal extent.
  By 1800 UTC the LLCC was near the southwestern edge of the deepest
  convection which had continued to increase in extent with cooling
  cloud tops.  The depression seems to have reached its peak organization
  about this time but there was still evidence of fairly strong vertical
  shearing.  Gales were reported to be occurring within 40 nm of the
  center from the north around the eastern side into the southwestern
  quadrant of the system.

     Thereafter the LLCC began to be sheared farther and farther away
  from the convection as the depression continued to move southeastward
  into a region of increasing vertical shear.     By 26/0000 UTC the
  system was entering Wellington's AOR, and gales were expanding in
  area, indicating that extratropical transition was beginning.

     Occasionally, in most tropical cyclone basins, poorly-organized
  depressions will be seen with little deep central convection but with
  peripheral gales on the poleward side due to a tight pressure gradient
  with a neighboring area of high pressure.   The basic definition of
  a tropical cyclone in WMO Region 5 (Australia and the South Pacific)
  contains the requirement that sustained gale-force winds should
  surround the center before a developing depression is named as a
  tropical cyclone.   This criterion was ostensibly added to provide
  some objective guidance for weeding out poorly-organized systems which
  might contain gale-force winds but which do not have the appearance of
  a typical, developing tropical cyclone.

     In the case of TD-08F, the gales never surrounded the center, but
  they were very close to the center--within 30-40 nm, based upon the 
  warnings from Nadi.      In looking at the depression in some infrared
  satellite imagery, to me it appeared to be similar to some sheared,
  weak tropical storms which I've seen in the Atlantic; however, I do
  not have available any Dvorak ratings on this system from any agency.
  To my knowledge, NPMOC at Pearl Harbor did not issue any warnings or
  alerts on this depression, which suggests that it was poorly organized
  with only a very low potential for development.

                   Tropical Cyclone Jo  (TC-07P / TC-09F)
                              23 - 28 January

     A weak disturbance was first identified over the northern parts of
  Vanuatu on the 19th, embedded in an active and slow-moving monsoon 
  trough.   On the 20th the disturbance was located to the south of the 
  250-mb ridge with northwest winds of 40 kts to 55 kts above it. 
  Strong vertical shear had arrested development, which was also strongly
  influenced by diurnal effects.   However, atmospheric pressure at the
  surface continued to gradually fall, but within a fairly broad area
  surrounding the system.   At 21/2100 UTC, a LLCC could be located by
  satellite about 300 nm northeast of Port Vila in Vanuatu and about 
  340 nm northwest of Nadi in Fiji; hence, the upgrade to tropical 
  depression phase.     The potential for development into a tropical
  cyclone in the next 24 hours was still low as shear was still
  significant over the system.  However, on the 22nd shear was gradually
  decreasing and pressure was also falling at a steeper rate.   By the
  23rd convection had significantly increased with slight improvement in
  organisation.  The depression was then located in a relatively weakly 
  divergent area at 250 mb; hence, at 22/2100 UTC the potential for this
  depression to develop into a cyclone in the next 24 hours was assessed
  to be moderate to high. 

     The first Tropical Disturbance Advisory on this system was issued
  at 23/0000 UTC when it was centered about 460 nm northwest of Nadi and
  expected to drift slowly southeastward.    Deep convective tops were  
  cooling and organisation, as well as outflow, was continually 
  improving.   Aloft, the depression was placed along the subtropical
  ridge axis in a very favourable area for further intensification.
  Gale warnings were also issued around this time, though over certain
  sectors only.   Overnight TD-09F continued to develop while moving
  slowly southward, with cold spiral bands beginning to wrap around the
  LLCC.   At 24/0300 UTC the depression was named Tropical Cyclone Jo
  with winds of 35 to 40 kts close to the centre, which was located about
  240 nm west of Nadi.  The cyclone was moving south-southeastward at 
  about 10 kts. 

     Tropical Cyclone Jo attained storm-force intensity 15 hours later,
  at 24/1800 UTC, with gales spreading to within 80 nm of the centre.
  Cold spiral bands were still wrapping tightly around the centre.  Warm
  air intrusion was quite evident on satellite imagery throughout most of
  the life of Jo while inside Nadi's area of responsibility.  This, to an
  extent, made locating the LLCC a little difficult while also preventing
  the system from attaining hurricane intensity.  Jo's intensity peaked
  around 26/0000 UTC, while it was situated about 350 nm south of Nadi,
  with a MSW of 60 kts close to the centre.    Gales gradually spread
  out from the centre to about 180 nm in the southeast semi-circle and 
  to 150 nm elsewhere around 26/1200 UTC.

     Jo's closest approach to Fiji on its way towards the southeast was
  on 24 Jan when the centre was located about 240 nm to the west-
  southwest.      The system had originally been tracking more south-
  southeastward but gradually turned to the southeast under a west to
  northwest steering flow on the 25th.     With gales fanning out more, 
  strong 10-minute average winds to 32 kts with gusts to 50 kts were
  affecting the western parts of Fiji's largest island, Viti Levu, and
  nearby islands to its south.   Frequent squally rainbands lashed these
  areas from late on the 24th until late on the 26th, inducing flash 
  flooding.   There was no major river flooding reported.   On the 25th
  a building 500-mb ridge from the east prevented any closer approach of
  Jo to Fiji.   This ridge was basically responsible for keeping the
  cyclone on its southeasterly track, entering Wellington's AOR around
  26/1200 UTC.   Wellington assumed primary responsibility for warnings
  on Jo after this time.     Tropical Cyclone Jo was finally declared 
  extratropical at 28/0600 UTC when located well over 1000 nm east of
  New Zealand's North Island and a similar distance southwest of Tahiti.

     No damage reports in Fiji have been received as yet.  If any become
  available later they will be reported in a future summary.

     Position and intensity estimates by JTWC compared extremely well
  with those from Nadi for Tropical Cyclone Jo.   As was the case with
  Tropical Cyclone Iris, JTWC's and Nadi's peak 1-min avg and 10-min
  avg MSWs were 65 kts and 60 kts, respectively.


                              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, 1998 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: []
       (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:   jan00.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:  jan00.sum, for

    Back issues can also be obtained from the following websites
  (courtesy of Michael Bath, Michael V. Padua, Tom Berg, Michael
  Pitt, and Rich Henning):>>>>>

     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:>


     I have discovered that JTWC now has available on its new website
  the complete Annual Tropical Cyclone Report for 1997 (1996-1997 season
  for the Southern Hemisphere).   Also, tracks only for the 1998 tropical
  cyclones are currently available.

     The URL is:>

     Also, TPC/NHC has available on its webpage nice "technicolor"
  tracking charts for the 1999 Atlantic and Eastern North Pacific
  tropical cyclones; also, preliminary storm reports for all the 1999
  Atlantic and most of the Eastern North Pacific cyclones are now

     The URL is:>

  Prepared by: Gary Padgett
  E-mail:  [email protected]
  Phone:  334-222-5327 (nights & weekends) / 850-882-2594 (weekdays)


Document: summ0001.htm
Updated: 4th January 2007

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