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


                             DECEMBER, 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.)


                          DECEMBER HIGHLIGHTS
  --> Intense tropical cyclone strikes Northwestern Australia
  --> Intense typhoon rapidly intensifies, then rapidly weakens
  --> Cyclone of hurricane intensity strikes Sri Lanka


              ***** Feature of the Month for December *****

                                 (Part 3)

     This is Part 3 of a three-part feature detailing cyclonic systems
  of 2000 in the Atlantic which were either subtropical storms or
  depressions or else exhibited some of the features of subtropical
  cyclones.  The information presented below is taken from material
  supplied by David Roth of HPC.  Please refer to Part 1 in the October
  summary for more background information and some explanations and

     I am repeating here the table of subtropical/hybrid systems which
  David provided.     (Numbers in parentheses following the storm
  designation refer to explanatory notes below.)

     I.     Subtropical Depression       May 19-25                
    II.     Alberto  (1)                 August 14-16             
   III.     Subtropical Storm  (2)       August 28-30             
    IV.     Subtropical Depression       September 10-11        
     V.     Florence  (3)                September 10-12          
    VI.     Gordon  (1)                  September 17-18         
   VII.     Helene  (1)                  September 24-25         
  VIII.     Subtropical Storm  (2)       September 30-October 3  
    IX.     Leslie  (3)                  October 4-8             
     X.     Michael  (3)                 October 14-17            
    XI.     Subtropical Storm  (4)       October 25-28

  (1) The official NHC "best tracks" do not treat any portion of Alberto,
      Gordon, or Helene as subtropical.   In general, once a tropical
      cyclone has been named, NHC treats it as a tropical system through-
      out the remainder of its life--both operationally and in post-
      analysis--even if at some point it exhibited some subtropical

  (2) According to Jack Beven, these two systems possibly could qualify
      as subtropical storms pending a careful analysis of all the
      available data.  For the time being they should be regarded as
      possible subtropical storms.

  (3) Subtropical portions of the tracks of Florence, Leslie, and Michael
      are designated in the "best tracks" for these cyclones.  The dates
      of their subtropical phases, however, might not necessarily agree
      with those David has assigned above.

  (4) This storm has already been officially recognized as a subtropical
      storm by TPC/NHC.

     Part 1 (October summary), in addition to some introductory material,
  contained David's discussions of two of the systems occurring in
  October (Nrs VIII and XI in the table above).  The November summary
  (Part 2) featured some of the named tropical cyclones which exhibited
  hybrid or subtropical characteristics for part of their lives.  This
  final installment discusses the remaining subtropical systems which
  David identified: subtropical depressions in May and September (Nrs I
  and IV) and a possible subtropical storm in August (Nr III).

  I. Subtropical Depression, May 19-25.  Satellite images and surface
  analyses revealed a frontal wave developing south-southeast of Bermuda
  on the 17th.  Over the next couple of days, a 500-mb LOW cut off in
  its vicinity, leading to occlusion.  By the 19th the system became
  devoid of fronts and had entered the subtropical stage.  Its main
  nontropical characteristic was a dry slot that encircled the center on
  the 19th.  Development of the cyclone occurred over 24 C waters and
  convection was present well east and northeast of the center which
  slowly warmed its core.  The system reached its peak just as it entered
  the subtropical stage, and weakened steadily thereafter as upper-level
  winds out of the west began shearing the cyclone to the east, exposing
  a low-level swirl on the 20th.  The circulation became elongated on
  the 23rd with multiple circulation centers before becoming absorbed
  into a warm front on the 24th and 25th.  No gale-force winds were
  reported on the surface maps with this cyclone, though gales were
  possible.  The highest winds reported were 30 kts.   (Some information
  on this system was reported in the May global summary.)

  III. Possible Subtropical Storm, August 28-30.  Hurricane Debby had
  dissipated in the northwestern Caribbean on the 24th.  Some of its
  weather spread northward as a cold front was invading northern Florida.
  A tropical disturbance formed over 28 C waters in the inverted trough
  ahead of the cold front on the 28th near the Bahamas as a closed 500-mb
  LOW (with temps of -12 C at that level) was entering the scene from the
  mid-Atlantic.  The 29th featured a complex situation, as a mesoscale
  convective complex formed to the east of the northward-moving LOW and
  accelerated northeastward in an area (confirmed by ship reports) of
  uniform southerly winds.  The frontal boundary in the LOW's vicinity
  had weakened, and thunderstorms were constricted to its east side as
  winds aloft were westerly and its central pressure was falling.

     On the 30th a tight circulation formed off North Carolina with a
  small, concentrated area of thunderstorms as the LOW was swung around
  the 500-mb LOW.  Gale-force winds were reported by two buoys near the
  coast, but existed only briefly as the system soon moved inland near
  Wilmington and subsequently weakened.  Operationally this LOW was
  treated as a nontropical gale, but some local forecast discussions
  addressed the cyclone as subtropical with one or two believing it to
  be fully tropical.  However, a large dry slot was present to the south-
  west and south of the center--a definite nontropical characteristic.
  As the LOW moved inland, it dumped an average of 50-75 mm of rain near
  and to the right of its track from North Carolina west-southwestward
  into northern Georgia.  The closed low-level circulation dissipated
  near Atlanta on the evening of the 30th.

     More information on this system can be found in the global summary
  for August.  Jack Beven of TPC/NHC has indicated that all available
  data for this cyclone will be carefully examined to see if it qualifies
  for inclusion in the Best Track database as a subtropical storm.

  IV. Subtropical Depression, September 10-11.  A frontal wave formed
  southwest of Bermuda on the 9th.  The system quickly occluded and shed
  its frontal boundaries by the 10th while sitting over 26 C waters.  It
  moved eastward as a cold front approached on the 11th, moving south of
  the Azores.  By the 12th the circulation had been absorbed into this
  front.  The highest winds seen were 20 kts via ship reports and land
  observations, which were sparse.

                           ACTIVITY BY BASINS

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

  Activity for December: No tropical cyclones


  NORTHEAST PACIFIC (NEP) - North Pacific Ocean East of Longitude 180

  Activity for December: No tropical cyclones

  NORTHWEST PACIFIC (NWP) - North Pacific Ocean West of Longitude 180

  Activity for December: 1 tropical depression **
                         1 typhoon ++

  ** - treated as a tropical depression by PAGASA only

  ++ - system did not reach typhoon intensity until early January, 2001

  NOTE:  Most of the information on each cyclone's history presented in
  the narrative will be based upon JTWC's advisories, and references to
  winds should be understood as a 1-min avg MSW unless otherwise noted.
  However, in the accompanying tracking document I have made comparisons
  of coordinates with JMA (Japan) and the Philippines (PAGASA) when their
  positions differed from JTWC's by usually 40-50 nm or more.  A special
  thanks to Michael V. Padua, owner of the Typhoon 2000 website, for
  sending me the PAGASA and JMA tracks.

     In the title line for each storm I plan to reference all the cyclone
  names/numbers I have available:    JTWC's depression number, the
  JMA-assigned name (if any), JMA's tropical storm numeric designator,
  and PAGASA's name for systems forming in or passing through their area
  of responsibility.

              Northwest Pacific Tropical Activity for December

     As the month of December opened Tropical Storm Rumbia/Toyang was
  in the process of crossing the southern Philippines.  The storm moved
  westward into the South China Sea, weakened into a tropical depression,
  later re-intensified briefly into a minimal tropical storm, and finally
  dissipated near the southern tip of Vietnam.  (Please see the November
  summary for the full report on Rumbia.)

     A tropical disturbance developed early in the month east of the
  Philippines and moved westward into the central portions of the
  archipelago.  JTWC never issued any warnings on this system, although
  it was given a development potential of Fair on a couple of occasions.
  PAGASA, however, upgraded the system to a tropical depression on
  6 December and assigned the name Ulpiang.  Tropical Depression Ulpiang
  remained broad and disorganized but moved through the central
  Philippines where it brought very heavy rains which led to extensive
  flooding and loss of life.  Based upon PAGASA's track (forwarded to me
  by Michael V. Padua), Ulpiang's center crossed over the island of
  Samar, then through the cluster of smaller islands lying to the west of
  Samar, eventually reaching the vicinity of Mindoro where it weakened to
  the point that warnings were discontinued.

     According to Mike Padua, Naga City (his hometown) was flooded by
  the rains of Ulpiang.  Two stations south of Naga City (Lake Bato and
  Ligao) each recorded 200 mm of rain in the 24-hour period ending at
  6:00 am on the 8th.  Ocampo, located a short distance southeast of the
  city, recorded 160 mm in the same period.    While Naga City itself
  recorded only 68 mm, the city was flooded because it lies below sea
  level and is in the catchment basin of the Bicol River (including its
  tributaries).   At least 20 fatalities were caused by the depression's
  rains, the majority occurring on the island of Panay, although three
  persons were killed in a landslide in the Bicol region of southeastern
  Luzon.   More than 50,000 persons were displaced when floods inundated
  16 towns and Roxas City (on Panay).    Many roads and bridges were
  damaged and hundreds of hectares of rice fields and other farms were

     The final tropical storm of 2000 also became the first typhoon of
  2001.  Tropical Storm Soulik formed deep in the tropics east of the
  southern Philippines late in the month, moved generally northward,
  and as the month (and year) closed was headed northeastward out into
  the Philippine Sea and weakening.   However, on 3 January the storm
  intensified with extreme rapidity into an intense 115-kt midget
  typhoon which, after maintaining that intensity for only twelve hours,
  encountered strong vertical shear and dry air and dissipated almost as
  quickly as it had intensified.

                Typhoon Soulik  (TC-34W / TY 0023 / Welpring)
                       28 December - 5 January, 2001

  Soulik: contributed by the Federated States of Micronesia, is a
          traditional Pohnpei Chief's title

     The final NWP tropical cyclone of 2000 was at the same time the
  first typhoon of 2001.  After forming deep in the tropics east of
  Mindanao and peaking at 55 kts on 31 December, Tropical Storm Soulik
  had begun to weaken by 2 January and was forecast to continue to
  dissipate.  However, the capricious storm had other ideas.  The
  storm's intensity (based on JTWC's 1-min MSW estimates) literally
  exploded on 3 January, increasing from 45 kts to 115 kts in just 18
  hours!  And then after only 12 hours, the storm weakened from a 115-kt
  typhoon to a 25-kt dissipating depression in only 30 hours.  Episodes
  of such rapid intensification are rare in tropical cyclones, but none-
  theless do occur and emphasize why even weaker storms which may appear
  to be weakening should not be written off too soon.  Rapid dissipation
  of cyclones such as that exhibited by Soulik is also not common.
  Soulik's demise was reminiscent of the decay of Typhoon Jack in 
  December, 1989.  Jack weakened from 120 kts to 30 kts in a 30-hour

     An area of convection developed on 27 December about midway between
  Palau and Mindanao.  A broad LLCC was present with the most persistent
  convection to the north.  Vertical wind shear was weak and outflow was
  fair.   JTWC upgraded the development potential to Fair at 28/0600 UTC
  and issued a Formation Alert at 28/1930 UTC.  Organization had improved
  with increased convective banding noted.    A 28/1712 UTC TRMM pass
  depicted a fully-exposed LLCC located about 200 nm east of the island
  of Mindanao with the deep convection sheared to the north.  The trend
  toward further development continued and JTWC initiated warnings on
  TD-34W at 29/0000 UTC.   PAGASA also upgraded the disturbance to a
  tropical depression at the same time and named it Welpring.   A ship
  report at 29/0000 UTC about 60 nm west of the center indicated a
  northwesterly wind of 22 kts.  The initial warning indicated that the
  depression was quasi-stationary, but the next warning at 0600 UTC
  relocated the center about 100 nm to the north of the previous warning
  position based on visible satellite imagery and a 29/0143 UTC ERS-2
  scatterometer pass.  TD-34W/Welpring was moving slowly northward and
  was forecast to continue this motion due to the steering influence of
  a low- to mid-level ridge east of the system.

     PAGASA was already estimating the 10-min avg MSW at 30 kts, but JTWC
  increased their MSW estimate to 30 kts at 1200 UTC based on a synoptic
  ship report of 28 kts.  At 1800 UTC JTWC relocated the center of the
  depression once more, this time to the west as the convection was
  beginning to consolidate over the LLCC.  TD-34/Welpring had also begun
  to track to the northwest as it intensified.  A synoptic ship report
  of 35 kts around 30/0000 UTC led to the system's being upgraded to a
  tropical storm by JTWC, PAGASA and JMA, with JMA assigning the name
  Soulik.  Soulik's center at the time was located approximately 200 nm
  east of Surigao on the northern tip of Mindanao, moving northwestward
  at 9 kts.  This northwestward motion was forecast to come to a halt
  and a northeasterly track commence as a mid-latitude trough approached
  and weakened the ridge which was steering the storm.    This forecast
  soon came to pass.    At 30/1200 UTC Tropical Storm Soulik reached the
  westernmost point of its trajectory about 135 nm northeast of Surigao;
  by 1800 UTC the storm was moving northeastward.    Soulik's MSW had
  reached 55 kts (per JTWC) by 0000 UTC on 31 December and the cyclone
  maintained this intensity for three days before weakening some.  (JMA's
  estimated peak 10-min avg wind was 50 kts for the same 72-hour period.)

     During this time Soulik moved generally on a northeastward to
  east-northeastward course.  Interestingly, at 1200 UTC on the 31st,
  JTWC received satellite current intensity estimates of 45, 55, and
  77 kts.   The JTWC warning at 0000 UTC on 1 January noted that the
  storm was located at the tail end of a long front extending southeast
  across the Philippine Sea.    The convection had become elongated,
  although the LLCC still appeared to be organized.  At 1800 UTC JTWC
  relocated Soulik to a position 60 nm southeast of the previous warning
  position or about 625 nm west-northwest of Guam.   A 01/1534 UTC TRMM
  pass depicted a partially-exposed LLCC southeast of the isolated deep
  convection.  A 700-mb HIGH east of the Mariana Islands with an
  associated ridge extending southwestward over Mindanao was expected
  to continue steering Soulik east-northeastward.

     The storm continued to show signs of weakening on 2 January.  Areal
  extent of deep convection decreased and animated water vapor imagery
  revealed transverse banding just north of the system, indicative of
  strong westerlies aloft.  JTWC and JMA both decreased their respective
  MSW estimates to 45 kts at 02/0600 UTC.   Satellite imagery around
  1200 UTC showed that the LLCC was embedded about 60 nm under the cirrus
  cloud shield, but a 02/0906 UTC SSM/I pass depicted weakening banding
  and organization with a partially-exposed LLCC south of the deepest
  convection.  Soulik was forecast to continue weakening, but the storm
  maintained its intensity throughout the day.    The storm's forward
  motion had slowed, thereby allowing deep convection to consolidate once
  more around the center.  JTWC increased the MSW to 55 kts at 0000 UTC
  on the 3rd while JMA upped their maximum 10-min avg wind estimate to
  50 kts.  Soulik was at that time located about 570 nm south-southwest
  of Iwo Jima and moving northward at 5 kts.

     Shortly after 03/0000 UTC, however, the fireworks really started!
  Based upon satellite intensity estimates ranging from 65 to 115 kts,
  JTWC upgraded Soulik to a 105-kt typhoon at 0600 UTC.  The storm had
  intensified very rapidly during the previous six hours and sported a
  7-nm round eye.    A 200-mb analysis revealed an upper-level HIGH
  developing over the system and animated water vapor imagery depicted
  good outflow aloft.      Typhoon Soulik reached its peak estimated
  intensity of 115 kts (per JTWC) at 1200 UTC on 3 January when it was
  located about 500 nm southwest of Iwo Jima.   Satellite intensity
  estimates were ranging from 90 to 127 kts.   At its peak Soulik was a
  small, symmetric system with intense central convection.  50-kt winds
  extended outward from the center only 25 nm to the southeast and gales
  covered an area only 140 nm in diameter.    JMA's peak 10-min avg wind
  estimate for Soulik was 80 kts at 03/1800 UTC.   Even as the cyclone
  reached its peak, cooler, drier air was impinging on its northwestern
  quadrant and convection was beginning to elongate to the northeast.

     As noted earlier, the demise of Typhoon Soulik was not much less
  rapid than its intensification with the storm weakening (per JTWC's
  MSW) from 115 kts to 25 kts in 30 hours.   Strong vertical shear and
  colder, drier air that was entrained into the system were the primary
  culprits responsible for the quick extinction of Soulik.  The MSW had
  fallen to 65 kts--minimal typhoon intensity--by 1200 UTC on 4 January
  when it was located about 440 nm southwest of Iwo Jima, and 12 hours
  later Soulik was a dissipating depression.  The 1200 UTC warning noted
  that the weakening storm's motion had changed to the southeast, but the
  final JTWC warning at 05/0000 UTC relocated the center about 170 nm to
  the southwest of the previous analysis position (to a point about
  700 nm east of Catanduanes Island in the Philippines).  This relocation
  was based upon the first visible satellite pictures of the day.  The
  intensity was lowered from 50 kts to 25 kts with animated satellite
  imagery indicating a fully-exposed LLCC which was beginning to break
  down on the southern side.   (The JMV file for Typhoon Soulik, which
  may be considered a first cut at a Best Track, begins to move the storm
  back to the south-southwest at 04/1200 UTC and also reduces the MSW
  to 55 kts at 1200 UTC and to 40 kts at 1800 UTC.)     In its earlier
  stages Tropical Storm Soulik/Welpring approached to within about 100 nm
  of northern Mindanao in the Philippines and would likely have led to
  some enhanced rainfall in the region, but the author has learned of no
  damage or casualties resulting from this tropical cyclone.   If any
  come to light later they will be reported in a future summary.


  NORTH INDIAN OCEAN (NIO) - Bay of Bengal and Arabian Sea

  Activity for December: 1 tropical cyclone of hurricane intensity

  NOTE:  The tracking and intensity information for North Indian Ocean
  Basin tropical cyclones is based primarily upon operational warnings
  from the Joint Typhoon Warning Center of the U. S. Air Force and Navy
  (JTWC) at Pearl Harbor, Hawaii.  Occasionally some information may
  be gleaned from the daily Tropical Weather Outlooks and other bulletins
  issued by the Indian Meteorological Department (IMD), which is the 
  WMO's RSMC for the basin.
     The MSW are based on a 1-min averaging period, which is used by
  all U. S. civilian and military weather services for tropical cyclone
  warnings.  For synoptic observations in the North Indian region,
  both 10-min and 3-min average winds are employed, but IMD makes no
  attempt to modify the Dvorak scale for estimating tropical cyclone
  intensity; hence, a 1-min avg MSW is implied.  In the North Indian
  basin JTWC usually does not initiate warnings until a system is
  well-organized and likely to attain tropical storm status within
  48 hours.

             North Indian Ocean Tropical Activity for December

     As the month of December opened the remnants of Tropical Cyclone 03B
  (which had reached hurricane intensity in November) were moving west-
  ward across the Arabian Sea.     The system briefly regained minimal
  tropical storm intensity on the 3rd but had dissipated by the 6th
  several hundred miles off the coast of Somalia.  The final NIO tropical
  cyclone of the year formed on Christmas Day east of Sri Lanka and
  struck the island as a hurricane on the 26th.  The system then began
  to weaken, moved over the southern tip of India, and had dissipated
  by the 29th.

                         Tropical Cyclone  (TC-04B)
                               25 - 28 December

     Almost exactly a month after the last Bay of Bengal storm formed,
  another tropical cyclone formed in the Bay and also reached minimal
  hurricane intensity.  TC-03B in November had struck southeastern India
  near Pondicherry, but this month's TC-04B followed a very low-latitude
  track and became the first tropical cyclone to strike the island nation
  of Sri Lanka since TC-10B struck the island with 55-kt winds on
  12 November 1992.  That particular storm left 13 persons dead in Sri
  Lanka, and later claimed over 200 lives in extreme southern India
  where it struck with 70-kt winds on the 13th.  (This information was
  gleaned from some of Jack Beven's Weekly Global Tropical Cyclone
  Summaries, which were the predecessors to the current series of monthly
  summaries.)     TC-04B was the first tropical cyclone of hurricane
  intensity in the Bay of Bengal in the month of December since TC-08B
  in 1996.  (In 1998 TC-08A reached minimal hurricane intensity in the
  Arabian Sea in mid-December.)

     Because of its very low latitude (the northern tip is just south of
  10N), and also by virtue of its being located in a basin with a low
  frequency of tropical cyclone formation, Sri Lanka only rarely receives
  a direct strike by one of these storms.  At present the author does not
  know the last occasion prior to 2000 when a tropical cyclone of full
  hurricane intensity struck the island.  No hurricanes have struck Sri
  Lanka since at least 1987.   In November, 1978, a hurricane (designated
  as TC 21-78 by JTWC) struck the island with 95-kt winds near Batticaloa
  where sustained winds of 85 kts were reported two hours before the
  center reached the coast.     More than 1000 lives were lost in that
  cyclone and many thousands of acres of crops were destroyed by the
  storm's winds, rain, and associated storm surge.  (This information
  was taken from the 1978 Annual Typhoon Report from JTWC.)  

     A STWO issued by JTWC at 1800 UTC on 21 December mentioned that an
  area of convection had developed and persisted very deep in the tropics
  in the central Bay of Bengal.  The convection was in a region of weak
  vertical wind shear and a QuikScat pass indicated a possible LLCC.  The
  disturbance remained quasi-stationary over the next couple of days, and
  by the 23rd central convection had increased and a mid-level cyclonic
  circulation had begun to develop.   The system had moved westward and
  was located about 240 nm east of Sri Lanka at 23/0700 UTC when the
  first of two Formation Alerts was issued.   The disturbance continued
  to slowly become better organized and a second Formation Alert was
  issued at 24/0700 UTC when the LLCC was located approximately 140 nm
  east of Sri Lanka.  A 23/2338 UTC QuikScat pass indicated that the weak
  LLCC was located south of the main convection and JTWC estimated the
  maximum winds at 20-25 kts.

     The STWO issued at 24/1800 UTC noted that animated satellite imagery
  depicted a decrease in overall organization with some weakening of the
  convection; however, this trend apparently soon reversed itself:  at
  0600 UTC on the 25th JTWC issued the first warning on TC-04B with an
  initial warning intensity of 40 kts.  The cyclone was located about
  135 nm east of Sri Lanka and was drifting westward at 2 kts.  Satellite
  imagery indicated that the LLCC had moved under the deep convection,
  thus leading to the increase in Dvorak numbers.     A subtropical
  ridge to the north steered the storm slowly westward as it steadily
  intensified.   The MSW had reached 55 kts by 1800 UTC and animated
  infrared imagery showed improving organization with good outflow in
  all quadrants.      A 25/1602 UTC SSM/I pass depicted the primary
  convective band wrapping tightly into the system center.

     The center of TC-04B made landfall around 0600 UTC on 26 December
  in eastern Sri Lanka near Trincomalee with the MSW estimated at 65 kts.
  Although the cyclone weakened some while over land, it maintained its
  organization rather well.  By 0600 UTC on the 27th the storm's center
  had emerged back over water along the western coast of Sri Lanka with
  the MSW estimated at 50 kts.    The cyclone was forecast to slowly
  re-intensify for at least the next 48 hours, but this failed to happen.
  The intensity was decreased to 45 kts at 1800 UTC as satellite imagery
  had indicated weakening convection and decreasing organization during
  the previous few hours.  The center of TC-04B was located about 120 nm
  northwest of Colombo, Sri Lanka, but most of the deep convection lay
  to the west-northwest of the center over southern India.

     By 0600 UTC on 28 December the system had reached the coast of
  extreme southern India and was centered about 25 nm northeast of Cape
  Comorin.  Convection had continued to weaken and become less organized,
  and most of the deeper convection was sheared to the west-northwest of
  the LLCC.   JTWC decreased the MSW to 35 kts at 0600 UTC, and issued
  the final warning on the system at 1800 UTC with the rapidly weakening
  center still over land about 40 nm north-northwest of Cape Comorin.
  What little convection remained was very weak and displaced well north
  of the system's center; satellite imagery showed primarily low- and
  mid-level clouds near the center.

     Even though only a minimal hurricane at landfall, the cyclone was
  quite destructive to Sri Lanka.   Fortunately the death toll was low:
  seven fatalities was the highest reported number available to the
  author.  However, over 75,000 families were left homeless (upwards of
  half a million individuals) in the districts of Ampara, Batticaloa,
  Mannar, Anuradhapura, Trinacomalee, and Polonnaruwa.     The fishing
  village of Pulmudai was reportedly destroyed, and about 20,000 hectares
  of rice fields were damaged.   Many of the affected areas had already
  been experiencing flooding due to monsoon rains and the cyclone served
  to exacerbate the flooding.  (In the Ampara district 94,000 persons had
  been rendered homeless in late November due to flooding from monsoon
  rains.)   There was some wind-related damage reported:  several police
  stations and military camps had their roofs blown off due to strong
  winds gusting between 80 and 95 kts (more than likely estimated
  values).  Also, apparently many homes experienced the loss of their
  roofs--a report indicated that tens of thousands of people were being
  housed in temporary shelters due to the winds sweeping away the roofs
  of their houses.  In southern India, heavy rains reportedly fell in
  the Tuticorin region of Tamil Nadu state but no damage or casualties
  were mentioned in the press report.


  SOUTHWEST INDIAN OCEAN (SWI) - South Indian Ocean West of Longitude 90E

  Activity for December:  No tropical cyclones



  Activity for December:  1 severe tropical cyclone

  NOTE:  The primary sources of information for Australian Region
  tropical cyclones are the warnings and bulletins issued by the three
  TCWC's at Perth, Darwin, and Brisbane.   Information gleaned from
  JTWC's warnings was 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.
     A description of the Australian Cyclone Severity Scale, which is
  alluded to in the narrative below, can be found in Chris Landsea's FAQ
  on HRD's website:>

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

     A special thanks is due to Mark Kersemakers of the Darwin TCWC for
  forwarding to me a summary of Tropical Cyclone Sam.  Also, a special
  thanks to Carl Smith, a cyclone enthusiast who lives on Queensland's
  Gold Coast, for sending me a report he'd written on Sam from which I
  extracted some information.  Much tropical cyclone-related information
  can be found on Carl's website:>

                  Northwest Australia/Southeast Indian Ocean
                        Tropical Activity for December

     The 2000-2001 tropical cyclone season in northwestern Australia got
  off to a start in a manner remarkably similar to the previous year.  
  In early December, 1999, a very intense Cyclone John made landfall at
  Whim Creek, just east of Roebourne, as a Category 5 cyclone on the
  Australian Cyclone Severity Scale.  This year's Cyclone Sam made land-
  fall also as a Category 5 cyclone (perhaps only slightly less intense
  than John) in Western Australia, but about 400 km to the east near
  Bidyadanga, southwest of Broome.      (In 1999 a much weaker Tropical
  Cyclone Ilsa followed on the heels of John and made landfall a few days
  later in the same general area as this year's Tropical Cyclone Sam.)
  Actually, this was the third consecutive year to feature a December
  Category 5 cyclone making landfall in northwestern Australia.   In
  December, 1998, Severe Tropical Cyclone Thelma battered Darwin with
  hurricane-force gusts and eventually made landfall at peak intensity
  along the Kimberley coast near the Northern Territory/Western Australia
  border.  However, the 1998-1999 season had gotten off to a very early
  start with Cyclone Zelia forming farther out in the Southeast Indian
  Ocean in early October, followed by Alison in November and Billy in
  early December.

                   Severe Tropical Cyclone Sam  (TC-03S)
                               3 - 10 December

     The daily TWO from Darwin on 28 November mentioned that a broad
  area of low pressure had formed in the southeastern Arafura Sea west
  of the Cape York Peninsula.  The LOW moved steadily westward for the
  next few days, passing north of the Northern Territory's Top End on
  the 29th and 30th, and by 1 December had reached a point in the Timor
  Sea about 230 nm northwest of Darwin and became quasi-stationary.  A
  STWO issued by JTWC at 0300 UTC on 1 December indicated persistent
  convection in the area with fair outflow aloft.  The Darwin TCWC began
  issuing tropical cyclone advices on the LOW at 5:00 pm CST on the
  2nd (0730 UTC).  The center of the still-broad circulation was located
  about 250 nm northwest of Darwin and was moving slowly southwestward.
  The STWO issued by JTWC at 1800 UTC on the 2nd indicated that outflow
  had improved and convection was becoming increasingly organized.

     Darwin began issuing High Seas gale warnings at 03/0600 UTC as the
  LOW continued to show signs of further development.  The system moved
  generally very slowly southward over the next 24 hours and had reached
  the Kimberley coast by 0130 UTC on the 4th about 90 km (50 nm) east of
  Kalumburu.    The center of the LOW tracked farther inland as it
  moved west-southwestward over the north Kimberley region.  This track
  over land delayed the strengthening of the system, but once it moved
  back out over the warm Timor Sea waters, intensification proceeded at
  a steady pace.  At 04/1800 UTC the center of the LOW was relocated
  north of the previous position to a point on the coastline about
  180 km (100 nm) west-southwest of Kulumburu and 480 km (260 nm)
  northeast of Broome.  The center was moving westward at 8 kts out
  into the Timor Sea.

     JTWC issued a Formation Alert at 04/1700 UTC, noting that the system
  was beneath the subtropical ridge and the development potential was
  considered good.  The Perth TCWC assumed warning responsibility for the
  developing tropical cyclone at 04/2200 UTC as the center had moved west
  of 125E, and JTWC issued their first warning on TC-03S at 05/0000 UTC.
  The LOW was christened Tropical Cyclone Sam at 0400 UTC when it was
  centered about 75 nm north of Kuri Bay.    The 10-min avg MSW was
  estimated to be around 40-45 kts.  A 05/0958 SSM/I pass depicted a
  partially-exposed LLCC with convection displaced to the southwest.  At
  the time Sam was north of the subtropical ridge axis under 15 to 25-kt
  northeasterly flow which was inhibiting development somewhat.   The
  cyclone's intensity increased slowly for about 48 hours after being
  upgraded as it moved westward off the coast of Western Australia.
  Perth had increased the MSW to 55 kts by 2200 UTC on the 5th while
  JTWC's 1-min avg MSW was lower at 45 kts.   However, JTWC estimated
  that the peak 1-min avg MSW had reached 55 kts by 06/1200 UTC.  Sam's
  convective organization was improving and the storm was under favorable
  outflow aloft.  A 06/0945 UTC SSM/I pass depicted a primary band of
  convection on the west wrapping into the northern quadrant of the
  system.   At 1000 UTC on 6 December the cyclone's center was located
  approximately 170 nm north-northwest of Broome and moving toward the
  west-southwest at 5 kts.

     Sam's motion became increasingly southwestward during the evening
  (local) of the 6th.  JTWC increased the 1-min avg MSW to 65 kts in the
  07/0000 UTC warning based on satellite intensity estimates.  Animated
  satellite imagery depicted increasing organization with a tightly-
  curved banding eye feature, a feature which had been noted earlier in
  microwave imagery.  Perth's 10-min avg MSW was in good agreement: at
  2200 UTC the estimate was 60 kts and the intensity was increased to
  70 kts at 0400 UTC on the 7th, making Sam a Category 3 cyclone.  The
  storm's center was then located about 65 nm northwest of Broome, or
  approximately 90 nm north-northwest of Bidyadanga, moving south-
  southwestward at 6 kts.   During the late afternoon and evening (local)
  of 7 December Tropical Cyclone Sam began to intensify rapidly into
  a very severe cyclone.   Perth upgraded the storm to a Category 4
  cyclone at 1400 UTC (10:00 pm WST) and JTWC issued an offtime warning
  at 1800 UTC (JTWC normally issues warnings every 12 hours for Southern
  Hemisphere cyclones) to upgrade the MSW to 115 kts (up from 85 kts six
  hours earlier).  Sam was sporting a well-defined 25-nm diameter eye at
  this time, although the storm was under some moderate vertical wind
  shear.  (According to Mark Lander, around 07/1200 UTC the objective
  (digital) Dvorak rating for Sam reached T7.7!)

     The cyclone, after moving to the south-southwest, slowly jogged for
  awhile a bit more to the southwest before turning southeastward toward
  the coast.   By 2000 UTC Perth had upgraded Sam to a Category 5 cyclone
  with an estimated CP of 920 nm and peak gusts estimated at 150 kts--
  corresponding to a maximum 10-min avg wind of about 105 kts.   Sam
  became almost stationary for a few hours about 65 nm northwest of
  Bidyadanga before commencing the southeastward movement that would
  carry it inland near the same community.    At 0600 UTC on 8 December
  JTWC increased the 1-min avg MSW estimate to the peak value for the
  storm of 125 kts.   The eye, well-defined and about 15 nm in diameter,
  was centered about 40 nm west-northwest of Bidyadanga, moving south-
  eastward at about 7 kts.   The center of Severe Tropical Cyclone Sam
  crossed the coast just west of Bidyadanga around 1100 UTC (7:00 pm WST)
  on 8 December at its peak intensity.    By 1600 UTC the eye had just
  about completed crossing the coast with the center inland to the south
  of Bidyadanga.   Convection was beginning to weaken but radar imagery
  revealed a strong convective band northwest of the eye moving onshore
  near La Grange Bay.

     After making landfall the powerful cyclone continued moving south-
  eastward across the Great Sandy Desert as it slowly weakened.  By
  08/2200 UTC the center of the by-now Category 3 cyclone was located
  approximately 100 km south-southeast of Bidyadanga with peak gusts
  estimated at 110 kts.   The final warning from JTWC was issued at
  0600 UTC on 9 December with the MSW (1-min avg) still estimated
  at 65 kts.  The warning noted that although convection was weakening,
  Sam still maintained some tightly-wrapped banding features.    At
  09/1000 UTC Sam's center was located 165 km northeast of Telfer and
  moving southeastward at 15 km/hr.  Gusts exceeding hurricane force were
  still reported to be occurring near the center.   The storm was down-
  graded to a Category 1 cyclone at 1300 UTC, and the final advice was
  issued on the weakening Sam at 1200 UTC on the 10th (8:00 pm WST),
  placing the center about 305 km east of Telfer.  The advice indicated
  that there was still a possibility of a few gales with gusts reaching
  near 50 kts, but those were expected to moderate within a few hours.
  The remnants of Tropical Cyclone Sam persisted as a rain-bearing LOW
  for several days as it drifted eastward across northern Australia.

     Most of the 200-plus residents of the Aboriginal community of
  Bidyadanga were evacuated before the cyclone struck; however, press
  reports indicated that around 30 persons elected to remain behind and
  ride out the storm (although a later report mentioned that only three
  people refused to leave).    Major structural damage appeared to be
  light with only a few buildings severely damaged, but many trees, power
  lines, sheds and fences were downed.  The Anna Plains homestead station
  south of Broome was extensively damaged with staff quarters and sheds
  demolished.  The station also lost power and water during the cyclone.
  Shelamar reported 520 mm of rainfall in the 48 hours ending at 9:00 am
  on 11 December, but most of this likely fell within a 24-hour period
  since the community was evacuated for a time and no 24-hour reading
  was taken.

     There was a report from Reuters that 163 illegal immigrants were
  feared drowned after two boats which had left Indonesia, bound for the
  Ashmore Islands (about 600 km off the coast of northwestern Australia),
  had been caught in Tropical Cyclone Sam and sank.  A Japanese tanker
  reportedly picked up four survivors.  This story has apparently never
  been confirmed, but there is no reason to doubt it since five boatloads
  of illegal immigrants did arrive in Australian waters in the week
  following the cyclone, proving that refugee-laden boats were in the
  area at the time.



  Activity for December:  1 tropical LOW

  NOTE:  The primary sources of information for Australian Region
  tropical cyclones are the warnings and bulletins issued by the three
  TCWC's at Perth, Darwin, and Brisbane.   Information gleaned from
  JTWC's warnings was 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.

                       Northeast Australia/Coral Sea
                       Tropical Activity for December
     No tropical cyclones formed in the Gulf of Carpentaria or Coral Sea
  during December; however, a tropical LOW formed on the 4th very near
  the tip of the Cape York peninsula and moved southwestward across
  the Gulf, making landfall around 0130 UTC on the 6th about 90 nm south-
  west of Alyangula or about 75 nm west-northwest of Port McArthur.
  The Brisbane TCWC issued three advices on the LOW before passing
  warning responsibility to Darwin.  It was initially felt that the LOW
  might develop into a tropical cyclone, but by the time Darwin had
  assumed responsibility for issuing advices, the system had not gotten
  any better organized and was rapidly approaching the coastline in the
  southwestern Gulf of Carpentaria region.   One factor which probably
  worked against this LOW's developing into a cyclone was its somewhat
  rapid rate of movement:  for most of its life it moved southwestward
  across the Gulf at speeds of around 16 to 19 kts--rather fast for that
  part of the world--which likely made it more difficult for the system
  to consolidate its convection, and if nothing else, significantly
  decreased the time spent over the warm waters of the Gulf before making


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

  Activity for December:  2 tropical depressions

  NOTE:  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.  

              South Pacific Tropical Activity for December

     There were no tropical cyclones in the South Pacific basin during
  December, but the Nadi TCWC did issue gale warnings on two tropical
  depressions during the month.   TD-01F formed about 200 nm west of
  Fiji on 11 December and moved eastward toward the islands.  Apparently
  no gales actually occurred during this phase of the system's life and
  advisories were discontinued at 12/2100 UTC as the system was moving
  southeastward into an area of increased shear and cooler SSTs.  Gale
  warnings, however, were re-initiated at 14/0000 UTC.  The depression
  by this time had moved rapidly eastward and was located about 300 nm
  east-southeast of the Kingdom of Tonga.  Some gales were occurring over
  an extensive area along the southern periphery of the system, but it
  seems likely that the depression was not fully tropical during its
  latter warning phase.  The system remained quasi-stationary in the area
  until the final gale warning was issued at 15/1200 UTC.

     A report from the Office for the Coordination of Humanitarian
  Affairs stated that a tropical depression (which undoubtedly must have
  been TD-01F) crossed Fiji and brought gusty winds, thunderstorms and
  bands of continuous rainfall.  Rivers reportedly burst their banks,
  flooding low-lying areas.  Two persons drowned and two others were
  reported missing at sea.  Roads and bridges were submerged in some
  areas and power outages were reported.   Minor landslides occurred and
  damage was reported to root crops and other vegetables.

     Another tropical depression (likely more of a hybrid) formed far to
  the southeast of Tahiti (about 375 nm west-northwest of Pitcairn) on
  18 December.  This system was accompanied by some peripheral gales well
  north and east of the center.  The system moved fairly quickly eastward
  and the final warning, issued at 19/1200 UTC, placed the center about
  275 nm east of Pitcairn Island.


                              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
  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
           December as an example:   dec00.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:  dec00.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):>> OR>>>>

     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 website the
  complete Annual Tropical Cyclone Report (ATCR) for 1999 (1998-1999
  season for the Southern Hemisphere).  Also, ATCRs for earlier years
  are available also.

     The URL is:>

     Also, TPC/NHC has available on its webpage nice "technicolor"
  tracking charts for the 2000 Atlantic and Eastern North Pacific
  tropical cyclones; also, preliminary storm reports for all the 2000
  Atlantic and Eastern North Pacific cyclones are now available. 

     The URL is:>

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


Document: summ0012.htm
Updated: 29th December 2006

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