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Monthly Global Tropical Cyclone Summary November 2001
[Summaries and Track Data] [Prepared by Gary Padgett]

                             NOVEMBER, 2001

  (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.)


                            NOVEMBER HIGHLIGHTS
  --> Most active November on record in Atlantic with three hurricanes
  --> Most intense hurricane since 1952 strikes Cuba
  --> Much loss of life in Philippines from tropical cyclone rains
  --> Scattered activity in the Southern Hemisphere


               ***** Feature of the Month for November *****


     This month's feature is a potpourri of various topics relating to
  the 2001 Atlantic hurricane season.    I have arranged it into three

  (1) Some interesting statistics concerning the active late season
  (2) Brief review of subtropical/hybrid activity
  (3) Links to official storm reports for June through September
      cyclones with a few additional comments

  1. Some interesting statistics concerning the active late season

     Overall the 2001 Atlantic tropical cyclone season was one of the
  more active ones on record, with 15 named storms, 9 hurricanes, and
  4 intense hurricanes (Category 3+ on the Saffir/Simpson scale).  The
  above-normal overall activity for the season was due in large measure
  to the very active period from October through early December.  Prior
  to 1 October there had been 8 named storms, 4 hurricanes, and 2 intense
  hurricanes--about average, although the complete dearth of hurricanes
  through the end of August was very unusual.  However, the final two
  months of the season produced 7 tropical storms and hurricanes--the
  highest since 1887 when there 9 post-September cyclones (including two
  which formed in December).

     Another new record was the highest number of hurricanes forming
  after 30 September.  There were 5, breaking the previous record of
  4 set in 1887, 1950 and 1969.  With regard to post-August activity,
  2001 set a new record for the highest number of hurricanes forming
  after 31 August.  There were 9, the previous high being 8 hurricanes
  in 1969.  Also, 2001 produced 11 tropical storms after August, the
  first such occurrence since 1969.   The season continued the string
  of very active seasons which began in 1995, broken only by the quiet
  El Nino season of 1997.  Since the big turnaround in Atlantic tropical
  activity in 1995, there have been 94 named storms, 58 hurricanes, and
  27 intense hurricanes.    By way of contrast, the previous 10-year
  period (1985-1994) produced 90 named storms, 49 hurricanes, and 14
  intense hurricanes.

  2. Brief review of subtropical/hybrid activity

     David Roth, a meteorologist at the Hydrometeorological Prediction
  Center in Maryland, has provided me with a list of systems which he
  classified as subtropical storms or depressions during 2001.  David's
  primary criterion for inclusion was classification of a system on the
  Hebert/Poteat scale for subtropical cyclones.  It should be clearly
  understood that TPC/NHC does not always regard an ST-number assignment
  on the Hebert/Poteat scale as a sufficient criterion for classification
  as a subtropical cyclone.   Many forecasters and researchers use the
  terms "subtropical" and "hybrid" interchangeably, but NHC in practice
  employs a much more restrictive definition of a "subtropical storm".

     To be officially classified as a subtropical storm (either
  operationally or in post-analysis), a system must have no evidence of
  surface fronts and display quite well-organized convective banding.
  The primary rationale for inclusion of subtropical cyclones
  in the Atlantic "best track" database is the belief that many such
  systems prior to the satellite era were treated as tropical cyclones,
  and to not include them now would introduce a bias in the historical
  data set.   Some of the systems not classified operationally as sub-
  tropical storms nor so classified by the end of the season may still
  be reviewed for inclusion at a later date.

     Six of the systems on David's list constitute portions of the life-
  spans of named tropical cyclones.  For four of these:  Allison, Karen,
  Noel and Olga, the official "best track" classifies a portion of the
  track as a subtropical storm.  For Allison and Noel, the subtropical
  designation was added after-the-fact; Karen and Olga were operationally
  designated as subtropical storms before being named as tropical
  cyclones.  David also included Dean and Gabrielle in his list.  In the
  case of Dean, the tropical storm near the Leeward Islands dissipated
  and a very weak remnant LOW moved northward.  This interacted with a
  frontal trough, ultimately resulting in the redevelopment of a tropical
  storm south of the Canadian Maritimes.     As the system was
  re-intensifying in the North Atlantic it possibly had some subtropical
  characteristics, but the "best track" does not classify it as a sub-
  tropical storm.  The TPC/NHC advisories for Gabrielle make it plain
  that the storm did exhibit some pronounced subtropical features, but
  since the storm was being carried operationally all the while as a
  tropical storm or hurricane, the "best track" does not attempt to
  designate any portion of Gabrielle's history as a subtropical cyclone.

     The other three systems on David's list include a system in late
  April, another in early May, and a subtropical depression lasting
  from 22-25 July.  The April and May systems are described in the
  global tropical cyclone summaries for those months.  There were some
  reports of gale-force winds associated with them, but the systems
  did not display very strong tropical features and have not officially
  been classified as subtropical storms.   I have no further information
  on the July subtropical depression except its dates and maximum wind
  and minimum reported pressure--30 kts and 1008 mb.

  3. Links to official storm reports for June through September cyclones
     with a few additional comments

     In the October and November summaries I have included links to
  TPC/NHC's official storm reports for the tropical cyclones forming in
  those months, plus a few comments about changes made to the operational
  intensities during post-storm analyses as reflected in the official
  "best tracks" (BT).  I wanted to include the same information for the 
  earlier storms here for the benefit of interested parties.

 Cyclone                     Link                        Author(s)

 Allison>    Stacy Stewart
 TD-02>        Miles Lawrence
 Barry>      Jack Beven
 Chantal>    James Franklin
 Dean>       Lixion Avila
 Erin>       Richard Pasch/
                                                         Daniel Brown
 Felix>      Stacy Stewart
 Gabrielle>  Miles Lawrence/
                                                         Eric Blake
 TD-09>       Jack Beven
 Humberto>   James Franklin

  (a) Tropical Storm Allison - The peak operational intensity of 50 kts
      is retained in the BT.  The biggest change for Allison is that
      the system has been classified as a subtropical cyclone from
      10/0000 UTC until it became extratropical at 18/0000 UTC.  Most
      of this time it was quite weak (a subtropical depression) with
      winds of 25 kts or less, but reached subtropical storm intensity
      for about 18 hours on 11 June when it re-intensified over south-
      eastern Louisiana and southern Mississippi, and again for 12 hours
      on the 17th when located south of the New England coast.

  (b) Tropical Storm Barry - The primary change to the storm's intensity
      in the BT was the downgrading of Barry to a tropical depression 
      from 0000 through 1800 UTC on 4 August.  Reconnaissance aircraft
      could find no evidence of gale-force winds, but since tropical
      storm warnings had already been issued, it was decided to keep
      Barry as a tropical storm unless it weakened further in order to
      lessen confusion should the storm re-intensify, which of course
      it did.  The operational peak intensity of 60 kts at landfall has
      been retained in the BT file.

  (c) Tropical Storm Chantal - Tropical Depression 04 was upgraded to
      Chantal in an intermediate advisory at 1200 UTC on 16 August.  
      A late-afternoon reconnaissance flight could find no closed low-
      level center, so the storm was downgraded to a tropical wave at
      17/0000 UTC.  During the post-storm analysis it was concluded that
      the depression likely had lost its circulation by 16/1200 UTC, so
      the BT file reduces it to tropical wave status at that time.  
      However, even as a tropical wave the system had developed 35-kt
      winds by 17/0000 UTC, and the BT shows it becoming a tropical storm
      at 17/1200 UTC after a reconnaissance aircraft had closed off a
      low-level center.  The operational peak intensity of 60 kts has
      been retained in the BT file.

  (d) Tropical Storm Dean - There are not any noteworthy differences 
      between the operational and BT intensities for Dean.  The early
      peak of 50 kts and the latter one of 60 kts are both reflected
      in the BT file.  After the storm redeveloped south of the Canadian
      Maritimes, advisories were re-started at 27/0900 UTC.  The BT file
      shows Dean as having regained tropical storm status and intensity
      by 27/0000 UTC.

  (e) Hurricane Erin - For Erin the only differences between the BT and
      operational intensities concern the duration of the storm's peak
      intensity.   Operationally, Erin's peak MSW of 105 kts was main-
      tained for 24 hours and at 100 kts or greater for 30 hours.  How-
      ever, the BT keeps Erin at 105 kts for 18 hours and at Category 3
      status for 24 hours.  Also, the storm was upgraded to a hurricane
      at 1800 UTC on 8 September, but the BT delays the attainment of
      hurricane status until 09/0000 UTC.

  (f) Hurricane Felix - Very few differences--in the BT file Felix's
      period of peak intensity (100 kts) was reduced from 18 hours to
      12 hours.

  (g) Hurricane Gabrielle - Again only minor adjustments to intensity.
      The operational advisories gave the MSW at 14/0600 and 14/1200 UTC
      as 60 and 50 kts, respectively.  The BT reverses these, reporting
      50 kts at 0600 UTC and 60 kts at 1200 UTC.  As noted above, the
      advisory discussions (mainly on 15 September) pointed out that
      after crossing the Florida Peninsula and entering the Atlantic,
      Gabrielle did not resemble a tropical cyclone, but rather looked
      more like a subtropical cyclone or even an occluded frontal LOW.
      However, since the cyclone was maintained in the advisories as a
      tropical entity, the BT file likewise keeps Gabrielle as a tropical
      system until it became extratropical on 19 September.

  (h) Hurricane Humberto - As with the previous few tropical cyclones,
      there were few changes implemented in the BT file as compared with
      the operational MSW values.  In the BT file, Humberto is shown as
      reaching tropical storm intensity six hours earlier than in real
      time.  The first reconnaissance flight into Tropical Depression 10
      on 21 September found the system somewhat weaker than satellite
      imagery suggested.   The satellite appearance early on the morning
      of the 22nd implied a tropical storm, but the MSW was estimated at
      a more conservative 30 kts in the 1500 UTC advisory.  However, a
      reconnaissance flight during the early afternoon found a 50-kt
      tropical storm, so it was assumed that the surface MSW had "caught
      up" with the satellite signature during the night.   The BT file
      also indicates that Humberto reached hurricane intensity six hours
      earlier than in real time.  The peak operational MSW of 90 kts has
      been retained in the BT file.

                           ACTIVITY BY BASINS

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

  Activity for November:  3 hurricanes

  NOTE:  Much of the information presented below was obtained from the
  TPC/NHC discussion bulletins issued with every regular advisory.  All
  references to sustained winds imply a 1-min averaging period unless
  otherwise noted.   Some information was also obtained from the monthly
  summary for November prepared by the Hurricane Specialists and
  available on TPC/NHC's website.

                  Atlantic Tropical Activity for November
     As will be obvious to most readers of these summaries, I am way
  behind schedule, just as I was last year following active Atlantic
  and North Pacific seasons.  Happily, the official storm reports
  prepared by the staff of TPC/NHC for the Atlantic and Eastern North
  Pacific basins have now appeared on NHC's website.  So, just as I
  did last year, I am not going to write much about the October and
  November cyclones in those areas in order to facilitate getting
  caught up and back on schedule.   While the reports may not contain
  quite as much detail about certain aspects of the storms as I might
  have included, there is no need for me to spend time re-creating what 
  others have already accomplished.  I shall confine my remarks about 
  the cyclones for the latter two months of the season to pointing out 
  a few interesting features and tidbits that were not mentioned in the 
  NHC reports.  The reports are very nicely done and highly informative 
  with several figures and tables, including charts and maps of the 
  official analyzed "best tracks".  I will include links to the specific
  reports below in the section for each storm.

     Over the period 1950-2000, the month of November has produced an
  annual average of 0.5 tropical storms, 0.3 hurricanes, and 0.1 intense
  hurricanes.  November of 2001 was the most active month of November
  ever observed, at least since 1851.   Three tropical cyclones were
  active during the month and all three reached hurricane intensity.
  Michelle probably should count as an October named storm, but reached
  hurricane intensity and intense hurricane status in early November.
  November has produced two hurricanes on several occasions, but never
  three.  Michelle continued the trend seen in recent years of late-
  season intense Western Caribbean hurricanes.  Noel and Olga both
  originated as subtropical storms in the Atlantic with Olga following
  a very erratic track for over a week and keeping the tropical storm
  season active into early December.

                     November Atlantic Hybrid Systems

     The subtropical North Atlantic during November was remarkable for
  the high number of LOWs which formed and exhibited some signs of
  beginning the process of evolving into a subtropical or tropical
  cyclone.  Only Noel and Olga made the transition, but some of the
  others are worth mentioning.

  (1) System of 7 - 9 November:  A non-tropical low-pressure system
      about 600 nm south-southwest of the Azores was mentioned in a
      TWO issued by NHC.  There was sort of an elongated area of low
      pressure, and early on 8 November the northern portion of the
      LOW made an attempt to close off an eye feature which was main-
      tained for a few hours.  At 0600 UTC a ship located about 30 nm
      northeast of the center reported winds to 50 kts and a pressure
      of 1001.9 mb.  However, the eye disappeared and the circulation
      rejoined its frontal band.  (Most of this information came from
      David Roth--a special thanks to David.)  James Franklin of NHC,
      however, indicated that he felt the ship report could very well
      be in error, as it did not fit in with manual cloud track motions
      in the vicinity.  By the morning of 9 November the LOW was located
      about 150 nm southwest of the Azores.  Thunderstorm activity was
      minimal and it was moving over colder waters.  This was the last
      reference to this system by NHC.

  (2) System of 11 - 13 November:  Another non-tropical LOW moved from
      about 1100 nm east-southeast of Bermuda on the morning of the 11th
      to a position 1000 nm west-southwest of the Azores early on the
      13th.  Gale-force winds occurred well east of the center but the
      system did not develop significant subtropical characteristics.

  (3) System of 14 - 17 November:  A non-tropical low-pressure system
      had developed by the morning of 14 November between the east coast
      of Florida and the northern Bahamas.  The system produced gusty
      winds and heavy surf along the Atlantic coast of central Florida
      northward to the Carolinas.  The LOW initially moved slowly north-
      ward just off the Florida coast, then turned eastward and by
      midday on the 17th was located about 250 nm east of the northern
      Bahamas, moving east-southeastward.    Upper-level conditions
      remained unfavorable for tropical development, but the potential
      for such was mentioned in the TWOs issued by NHC.

  (4) System of 17 November:  A non-tropical LOW was located about 300 nm
      east-northeast of Bermuda around midday on 17 November.  The LOW
      was moving east-northeastward and had shown some increased organ-
      ization during the morning.  However, conditions were unfavorable
      for tropical development and the system was dropped from the TWOs
      after the 17th. 

  (5) System of 18 November:  Another non-tropical LOW was mentioned in
      the TWOs issued by NHC on 18 November in the far eastern Atlantic
      well south of the Azores.   Like the two preceeding systems this
      LOW was not located in an environment conducive to tropical cyclone

     I've saved the most interesting system til last.  A small system
  which looked like a small shear-type tropical cyclone formed in the
  eastern Atlantic west of the Straits of Gibraltar.   Mark Lander
  discovered this system while looking for a possible developing
  Mediterranean cyclone which Julian Heming had alerted him to.  Mark
  dubbed it a "Spaincane", although it was actually closer to Portugal.
  David Roth, while looking at satellite pictures for the remains of
  Hurricane Noel, also accidentally noticed this system.  Following is
  a partial track of the "Spaincane" which David sent to me:

  Nov 6 - 2100 UTC   34.8 N, 11.6 W
  Nov 7 - 0000 UTC   34.9 N, 11.7 W
  Nov 7 - 0300 UTC   35.1 N, 11.8 W
  Nov 7 - 0600 UTC   35.2 N, 11.9 W
  Nov 7 - 1800 UTC   35.8 N, 13.1 W
  Nov 7 - 2100 UTC   35.7 N, 13.4 W
  Nov 8 - 0000 UTC   35.8 N, 13.8 W
  Nov 8 - 0300 UTC   35.8 N, 14.1 W

     David indicated that to him, it at least looked like a small-scale
  tropical depression/storm on the tail end of a stationary front.  Water
  temperatures, however, were only around 18 C.   Mark Lander stated his
  opinion that he was "95% serious that this is a genuine tropical
  storm!"   Later, when David sent me his list of subtropical cyclones
  for 2001, he briefly discussed the "Spaincane".  David noted that the
  system was not classifiable using the Hebert-Poteat scale since it had
  no attachments to fronts aloft.   It had the tropical characteristic
  of being non-frontal, yet it was over cool SSTs with cold air aloft.
  A few months ago I discussed this system during a telephone conver-
  sation with Jack Beven.  Jack was of the opinion that the small cyclone
  did somewhat resemble a tropical system, but felt that it was quite
  weak.  If I learn anything further about this system, or at least get
  some more opinions on it, I'll include them in a future summary.

                       Hurricane Michelle  (TC-15)
                         29 October - 6 November

     Hurricane Michelle continued the trend seen during the past few
  years of late-season intense Caribbean hurricanes.  Late-season
  (October and November) hurricanes reaching Category 4 intensity on
  the Saffir/Simpson scale were not all that uncommon during the decades
  of the 1950s and 1960s.  Between 1952 and 1966, seven hurricanes were
  at Category 4 strength on or after 1 October:  Fox (1952), 
  Hazel (1954), Greta (1956), Hattie (1961--Cat. 5), Flora (1963), 
  Hilda (1964), and Inez (1966).  Between 1967 and 1994 there were only 
  two:  Gladys (1975) and Joan (1988).     Since 1995 there have been 
  six:  Opal (1995), Mitch (1998--Cat. 5), Lenny (1999), Keith (2000), 
  Iris and Michelle (2001).  Indeed, since 1998 the most intense hurri-
  cane of the season has occurred on or after 1 October (with Floyd in 
  September of 1999 being co-equal with Lenny).    Typical of November 
  tropical cyclones forming in the Western Caribbean, Michelle turned to
  the northeast while still in the Caribbean, thus missing the Florida 
  Peninsula.  However, the hurricane was the strongest to strike Cuba
  since Hurricane Fox in late October, 1952.     The storm spread
  destruction from Nicaragua and Honduras and Jamaica through Cuba to 
  the Bahamas.

     Comparing the official "best track" (BT) with the operational track,
  there were more than the usual number of small (5-10 kts) adjustments.
  Likely this is due to the fact that there was a lot of reconnaissance
  data available to sift through during post-storm analysis, and also due
  to Michelle's displaying the unusual characteristic of its peak winds
  not coinciding with the lowest measured central pressure.  The peak MSW
  reported operationally was 115 kts from 03/1200 through 04/1800 UTC.
  However, the BT reports the MSW at 120 kts at 0600, 1200, and 1800 UTC
  on 4 November.  The central pressure reported by reconnaissance air-
  craft was in the range of 944-950 mb during this period while the 
  minimum central pressure for the storm's history--933 mb--occurred at 
  1800 UTC on 3 November.      Operationally, tropical advisories on 
  Michelle were continued through 2100 UTC on 6 November.   However, the
  BT file indicates that Michelle had become extratropical by 06/0000 

     The death toll from Michelle stands at 17 persons:  6 in Honduras,
  5 in cuba, 4 in Nicaragua, and 2 in Jamaica.   Additionally, 26 persons
  have been reported as missing:  14 in Honduras and 12 in Nicaragua.  
  Widespread flooding was reported in Honduras and Nicaragua during the 
  storm's early stages with 100,000 people forced to flee their homes.  
  Some flooding was also reported in Costa Rica, and flash floods and 
  mudslides caused damage on Jamaica.  In the Cayman Islands the damage 
  estimate was placed at $28 million, the damage mainly occurring on 
  Grand Cayman.  

     Cuba was hardest hit by Michelle.  More than 12,500 houses were 
  totally destroyed with over 100,000 damaged.  The sugarcane crop was 
  especially adversely affected with the estimated losses in exports 
  totalling $60 million (USD).    Export losses in the citrus crop 
  industry were estimated at $27 million (USD).    The banana and plan-
  tain crops were largely destroyed in the three hardest-hit provinces 
  of Cienfuegos, Matanzas, and Villa Clara.    (More information about 
  the effects of Hurricane Michelle can be found on the Relief Web's 
  website:>.  Click on the Natural Disasters 
  link, then the Hurricane Michelle link.)

     The official TPC/NHC storm report on Hurricane Michelle, prepared 
  by Jack Beven, can be found at the following URL:>

                         Hurricane Noel  (TC-16)
                              1 - 7 November

     Hurricane Noel was one of three late-season hurricanes in 2001 to
  initially develop as a subtropical storm, the others being Karen and
  Olga.  However, unlike the other two, the pre-Noel cyclone was not
  classified operationally as a subtropical storm.  The system formed
  from an occluded frontal LOW which gradually shed its fronts and
  acquired a weak mid-level warm-core structure.  During its early
  stages the system was carried in the High Seas Forecasts issued by
  MPC.  The TPC/NHC "best track" (BT) starts the system at 0000 UTC on
  4 November, classifying it as a subtropical storm.  Convection, which
  had been limited and confined to the northern semicircle, became more
  symmetric and formed a ring around the center at a radius of about
  60 nm.  On the morning of the 5th a ship reported 65-kt winds, so NHC
  initiated advisories on Hurricane Noel at 1500 UTC, located several
  hundred miles south of Cape Race, Newfoundland.   Within twelve hours
  after being upgraded, cooler waters and increased shear were already 
  taking their toll on Noel, and the cyclone was downgraded to a tropical
  storm at 06/0000 UTC.  The storm had become extratropical by 1200 UTC 
  and was absorbed by a larger extratropical system later in the day.

     The official TPC/NHC storm report on Hurricane Noel, prepared by
  James Franklin, can be found at the following URL:>

                    Hurricane Olga  (TC-17 / STS #2)
                        23 November - 6 December

     Hurricane Olga, the final tropical cyclone of the active 2001
  season, formed from an initially non-tropical LOW which underwent 
  an evolution into a subtropical storm and eventually into a tropical
  cyclone.  Olga was the third Atlantic hurricane to originate as a
  subtropical storm, Karen and Noel being the others.  Noel, however,
  was not classified operationally as a subtropical storm; hence, Olga
  was numbered as Subtropical Storm #2 when advisories were initiated.
  After making an unusual double-cyclonic loop east of Bermuda, Olga
  was steered southwestward by a strong HIGH to its northwest to a point
  near the Bahamas.  This southwesterly track for a tropical cyclone
  late in the season is unusual, but certainly not unprecedented.  Some
  other late-season or out-of-season hurricanes which have followed
  southwesterly or southerly tracks in that general region include a
  November hurricane in 1934; the famous "Yankee" Hurricane which struck
  Miami in 1935; a hurricane in March, 1908, which struck the Leeward
  Islands; Hurricane Alice in January, 1955, which also struck the Lee-
  ward Islands; and more recently Hurricane Lili in December, 1984.
  As it neared the Bahamas, Olga encountered shear which caused it to 
  weaken into a tropical depression.  However, the shear had lessened 
  enough by early on 2 December that Olga was able to regain minimal 
  tropical storm intensity for about 48 hours, thus extending the 2001 
  tropical cyclone season several days into December.    Such an 
  occurrence is uncommon but not all that rare.  The last Atlantic storm
  to actually form in December was Lili in 1984, but Tropical Storm 
  Karen in 1989 and Hurricane Nicole in 1998, both of which formed in 
  late November, were still operating as tropical cyclones in early 

     Comparing the operational intensity estimates with the "best track"
  (BT) values, there were few changes.  The biggest difference between
  the two concerns the classification of the storm during its early
  stages.  Operationally, the pre-Olga system was treated as a typical
  non-tropical gale center in the High Seas Forecasts on 23 and early
  24 November.  Post-storm analysis (reflected in the BT file) indicates
  that the system had acquired subtropical characteristics by 24/0000 UTC
  with a comma-shaped cloud band extending east of a well-defined center
  and gale-force winds extending outward several hundred miles to the 
  north.  Later in the day a ship passed through the center and reported
  a pressure of 989 mb.    This report was the basis for initiating 
  advisories on Subtropical Storm #2 at 2100 UTC.  However, the cyclone 
  had already taken on a distinctive tropical appearance in satellite 
  imagery with hints of an eye.  The BT file now shows Olga becoming a 
  tropical storm at 1200 UTC on the 24th.  The storm consisted of a small
  tropical-like core within a larger extratropical cyclonic envelope.  
  The gale wind radii were much more typical of a non-tropical system, 
  and this was the rationale for classifying the cyclone as a subtropical
  storm rather than a tropical cyclone at that juncture.

     The storm gradually acquired more typical tropical characteristics 
  on 25 November and also intensified.  The first tropical advisory on
  the system, naming it Tropical Storm Olga, was issued at 1500 UTC on
  26 November with the center located several hundred miles east of
  Bermuda.  Olga was upgraded to a hurricane six hours later, but the
  BT file now indicates that Olga had reached hurricane intensity by 
  1200 UTC.  One interesting little difference between the operational 
  and "best track" is the time of the peak intensity of 80 kts.  In the
  real-time advisories, Olga's MSW was estimated at 80 kts at 27/1800
  and 28/0000 UTC.  However, the BT reduces the intensity at those times
  to 75 kts but raises the MSW to 80 kts at 27/0600 and 27/1200 UTC.

     The official TPC/NHC storm report on Hurricane Olga, prepared by
  Lixion Avila, can be found at the following URL:>


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

  Activity for November:  1 hurricane

              Northeast Pacific Tropical Activity for November

     The final Northeast Pacific tropical cyclone of the 2001 season,
  Hurricane Octave, was active during the first few days of November
  far to the southwest of Baja California.  However, Octave formed late
  in October and is counted as an October system.    A link to the 
  official TPC/NHC storm report for Octave (as well as all the 2001
  tropical cyclones) was included in the October summary.


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

  Activity for November:  2 tropical storms **
                          1 typhoon

  ** - One of these systems was classified as a tropical storm by only
       JTWC and PAGASA, and the other by JTWC only

  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 some of the Asian warning centers 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.   Also, a special thanks to
  Huang Chunliang of Fuzhou City, China, for sending me tracks based on
  warnings from the National Meteorological Center of China (NMCC), the
  Hong Kong Observatory (HKO), and the Central Weather Bureau of
  Taiwan (CWBT).

     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 November

     Only one typhoon formed during the month, Lingling, but it was quite
  destructive to the Philippines (where it was known as Nanang) and to
  Vietnam.   Two other tropical depressions developed which were both
  classified as tropical storms by JTWC.   These were never named by
  JMA, but PAGASA named them Ondoy and Pabling, respectively, when they
  entered that agency's AOR.   PAGASA also classified Ondoy (28W) as a
  tropical storm, but regarded Pabling (29W) as only a depression.

  NOTE: Following the narratives for the three November cyclones is a
  short addendum to the October summary.

              Typhoon Lingling  (TC-27W / TY 0123 / Nanang)
                            6 - 12 November

  Lingling: contributed by Hong Kong, is a fairly common pet name for
            young girls

  Nanang: PAGASA name, is a Filipino nickname

  A. Storm Origins

     A STWO issued by JTWC at 1900 UTC on 3 November noted that an area
  of convection had developed and persisted approximately 120 nm east-
  southeast of Yap.  Animated infrared satellite imagery indicated little
  organization of the convection.  A morning surface analysis revealed
  that the disturbance lay in a monsoon trough with no closed LLCC.  A
  200-mb analysis, however, showed that the convection was located in a
  favorable environment for intensification with good diffluence under
  the subtropical ridge axis.  Satellite imagery the next day indicated
  the presence of multiple LLCCs within a broad circulation.   JTWC
  upgraded the development potential to fair at 1400 UTC since an
  improvement in the organization of the convection had been observed.

     By 0600 UTC on the 5th the disturbance had moved westward and was
  located west of Yap, still showing evidence of multiple circulation
  centers.  JTWC issued a TCFA at 05/2000 UTC.  The subject area of
  interest was a large monsoon depression centered roughly 215 nm east-
  northeast of Mindanao.  A 05/1359 UTC TRMM pass depicted convection
  around the periphery with sparse convection near the center--a typical
  characteristic of a monsoon depression.  The system was still situated
  in a favorable environment with divergence aloft.  

     JTWC initiated warnings on Tropical Depression 27W at 06/0000 UTC
  with the center approximately 90 nm east-northeast of Mindanao, moving
  westward at 6 kts.    PAGASA also began issuing bulletins at the same 
  time and named the system Tropical Depression Nanang.  Both warning
  centers estimated the intensity at 25 kts.  PAGASA upgraded Nanang to
  a tropical storm at 0600 UTC as the system's organization continued to
  improve with an increase in convection as it neared the Philippines.
  By 1200 UTC Nanang's center was near the Leyte Gulf.  JTWC upped the
  MSW to 30 kts, although the coverage of deep convection had been 
  reduced somewhat with the majority confined to the western semicircle.
  JMA upgraded the depression to Tropical Storm Lingling at 1800 UTC with
  the center located over southern Leyte Island.  CI estimates at the 
  time were around 30 to 35 kts.  As Lingling/Nanang continued to move
  westward through the Philippine Archipelago, convective organization
  continued to improve with impressive outflow noted over the northern
  quadrant.  At 0000 UTC on 7 November, both JTWC and NMCC upgraded the
  cyclone to tropical storm status with the center located over northern
  Cebu island.

  B. Track and Intensity History

     Lingling/Nanang's intensity hovered near or just above minimal
  tropical storm intensity on 7 November as it moved generally west-
  northwestward through the Philippine Islands, steered by a low to
  mid-level ridge situated near the southern coast of China.   The
  system's organization gradually improved and water vapor imagery
  depicted good outflow, especially to the north.    At 1200 UTC the
  center was located near northern Negros Island and by 0600 UTC on the
  8th was over northwestern Panay Island.  Tropical Storm Lingling/Nanang
  maintained its deep convection as it passed through the Philippines but
  remained loosely-organized.   JTWC upped the MSW to 45 kts at 0000 UTC,
  and by 0600 UTC some CI estimates were reaching 55 kts.  At 1200 UTC
  on the 8th the cyclone's center was just south of the island of
  Mindoro.  JTWC increased the MSW to 55 kts as the system continued to
  become better organized with both equatorward and poleward outflow

     A TRMM pass at 08/2239 UTC revealed a banding feature wrapping
  around the southern periphery of the storm.  By 09/0000 UTC the center
  of Lingling/Nanang had moved through the Mindoro Strait into the South
  China Sea at a point about 185 nm southwest of Manila.   Satellite
  intensity estimates had reached 65 kts so JTWC upgraded the storm to
  typhoon status.   Typhoon Lingling continued its slow westerly to
  west-northwesterly march through the South China Sea on 9 November
  as convection continued to increase in coverage and organization.  JTWC
  increased the MSW to 90 kts at 1800 UTC and further to 100 kts at 0000
  UTC on 10 November.   Lingling reached its peak intensity of 115 kts
  at 0600 UTC and maintained it for 24 hours.   The storm at this time
  was located roughly 365 nm west-southwest of Manila or about 320 nm
  east of the Vietnamese coast.   JMA estimated the minimum central 
  pressure at 945 mb, and gales reached out 170 nm in all quadrants and
  up to 250 nm in the northwest quadrant.    Storm-force winds were
  estimated to extend outward 80 nm from the 25-nm diameter eye.
  Lingling was a rather strong typhoon for the South China Sea to
  experience so late in the year.

     The storm slowly weakened on the 11th as it approached the coast of
  Vietnam.  The ridge to the north remained intact and steered Lingling
  on a fairly straight westward course.  The typhoon made landfall just
  south of the city of Qui Nhon around 11/1930 UTC with winds estimated
  at 95 kts, gusting to 115 kts.  Lingling was downgraded to a 60-kt
  tropical storm at 0000 UTC on 12 November, and JTWC issued their final
  warning on the cyclone at 0600 UTC.  The MSW had dropped to 45 kts and
  satellite imagery indicated that Lingling was rapidly weakening over
  land about 110 nm west of the coast.  JMA continued tracking the system
  for 12 more hours before dropping it from their bulletins.

  C. Comparisons Between JTWC and Other Centers

     NMCC's peak 10-min avg MSW estimate of 100 kts was in excellent
  agreement with JTWC's peak 1-min avg MSW of 115 kts.  HKO's peak of
  95 kts was just a little lower, but was reported for only one 6-hour
  cycle while NMCC's 100-kt peak was maintained for 24 hours.  JMA's
  maximum 10-min mean wind was 85 kts from 10/1200 through 11/1200 UTC.
  There were some interesting differences in the intensity estimates at
  11/1800 UTC--the final warning time prior to landfall when Lingling's
  center was just off the coast of Vietnam.  JTWC reported 95 kts, based
  on a rather wide spread of CI numbers ranging from 4.5 (77 kts) to
  5.5 (102 kts).  NMCC agreed closely with JTWC, their estimate being
  80 kts (10-min avg).  HKO, however, was substantially lower at 65 kts,
  and JMA even lower at 55 kts, dropping the intensity 25 kts from the
  80 kts reported six hours earlier.   (Typhoon Lingling had departed
  PAGASA's AOR prior to reaching its peak intensity.)

  D. Damage and Casualties

     Typhoon Lingling/Nanang was a very deadly event in the Philippines.
  I have located sources quoting varying numbers of deaths.  The Annual
  Tropical Cyclone Report prepared by JTWC reports 171 confirmed deaths
  and 118 missing.  A report on the website of ReliefWeb from the Office
  for the Coordination of Humanitarian Affairs (OCHA) states that over
  200 persons were killed with almost as many missing and presumed dead.
  The majority of the deaths seem to have occurred on the small resort
  island of Camiguin lying just west of northern Mindanao.  Cloudbursts
  during the night created widespread flash flooding which caught people
  while they were sleeping.  Over 40,000 persons were displaced by the
  flooding with 1000 homes destroyed and almost 3000 damaged.  Total
  damage in U. S. dollars was estimated at $22.7 million.

     In Vietnam where Lingling made its final landfall the death toll was
  much lower, due in part to evacuation of thousands of residents in the
  path of the storm.  The highest Vietnamese death toll located by the
  author was 20, with 131 persons reported as injured.  Even though the
  death toll was relatively low, Lingling was a destructive typhoon to
  Vietnam.  Over 1000 houses were destroyed with several thousand more
  damaged.  Heavy rains were also a big factor in the damage sustained
  by Vietnam from the storm.  Over 10,400 hectares of rice paddies were
  inundated and destroyed while almost 19,000 hectares of subsidiary
  crops were destroyed by flooding.  Over 30,000 banana trees were
  destroyed, and the sugarcane and tobacco crops were hard hit also.
  Almost 40,000 hectares of shrimp ponds were damaged and over 1400 small
  boats were swept away.  In addition, much soil erosion was caused by
  the typhoon's heavy rains.   The total damage estimate in Vietnam
  resulting from Typhoon Lingling was placed at $37.3 million in U. S.
  dollars.  (More information on the effects of Lingling can be found at
  the following URL:>.  Click on the Natural
  Disasters link on the left side of the screen.)

                   Tropical Storm  (TC-28W / Ondoy)
                           17 - 25 November

  Ondoy: PAGASA name, is a Filipino nickname

  A. Storm Origins

     An area of convection with an associated weak LLCC had developed by
  14/0600 UTC about 170 nm west-southwest of Pohnpei.  The disturbance,
  embedded in the monsoon trough, displayed unorganized, cycling
  convection which was limited to the southern periphery of the LLCC.
  Upper-level conditions were marginal, but were forecast to become more
  favorable as a TUTT located to the east continued moving westward.  At
  15/0600 UTC the disturbance was relocated to a position about 240 nm
  southwest of Pohnpei.  By 0600 UTC on the 16th the system was located
  roughly 300 nm southwest of Chuuk.  Convection was getting better
  organized, outflow was fair, and shear was weak; therefore, JTWC
  upgraded the development potential to fair.   A few hours later, at
  1400 UTC, JTWC issued a TCFA.  The disturbance was then located about
  470 nm southeast of Guam with a banding feature beginning to form in
  the northeast quadrant.

     The system, which consisted of a broad circulation embedded in a
  monsoon trough, was relocated once more at 17/0600 UTC to a position
  approximately 320 nm south of Guam.  Also at 0600 UTC, JMA classified
  the disturbance as a 30-kt depression.  (JMA never upgraded the system
  to a tropical storm and maintained it as a 30-kt depression for its
  entire life.)  JTWC re-issued the TCFA at 1400 UTC, and at 0600 UTC
  on 18 November the depression was located approximately 200 nm south-
  west of Guam.  Animated multi-spectral satellite imagery revealed
  an elongated LLCC with cycling convection near the circulation.  
  Conditions remained favorable for further intensification, and at
  1200 UTC JTWC issued the first warning on Tropical Depression 28W.
  The depression at the time was centered about 160 nm southwest of
  Guam, moving northwestward at 7 kts with an initial intensity of
  25 kts.

     At 1200 UTC on 19 November TD-28W was located approximately 290 nm
  north-northeast of Yap, moving west-northwestward at 9 kts.   The MSW
  was still estimated at 25 kts, and a SSM/I pass indicated little
  improvement in overall organization.  The depression lay under the axis
  of a near-equatorial ridge with fair outflow and weak vertical shear,
  so further intensification was considered likely.   JTWC upped the MSW
  to 30 kts at 20/0000 UTC when the depression's center was located
  roughly 300 nm north-northwest of Yap.     Satellite imagery indicated
  a partially-exposed LLCC just southwest of deep convection.  At 0600
  UTC the system passed about 420 nm north of Palau, moving westward at
  a rather quick 16 kts.  By this time TD-28W had entered PAGASA's AOR
  and had received the name Ondoy.  JTWC upgraded Ondoy/28W to a tropical
  storm at 1200 UTC based on CI estimates of 30 and 35 kts.     The
  cyclone's motion had changed to west-southwesterly at a slower pace
  of 9 kts.

  B. Track and Intensity History

     Tropical Storm Ondoy/28W reached its estimated peak intensity of
  40 kts (per JTWC's analysis) at 1800 UTC on 20 November when located
  about 400 nm north-northwest of Palau.  At 21/0000 UTC satellite CI
  estimates were 35 and 45 kts, but imagery revealed a partially-exposed
  center southwest of the deep convection, so JTWC decreased the
  intensity to 35 kts.  (Interestingly, PAGASA upgraded Ondoy to tropical
  storm status at this time.)    At 1200 UTC intensity estimates were 25
  to 30 kts, so JTWC downgraded Ondoy/28W back to tropical depression
  status.  The system was then located about 325 nm east-southeast of
  Catanduanes Island, moving west-southwestward at 16 kts.  The JTWC
  warning at 21/1800 UTC reported that the depression was moving north-
  northwestward, but the next warning relocated the center 95 nm south-
  southwest of the previous warning position.  Over the next day or so
  the center of Ondoy/28W dropped farther to the south, then moved north-
  westward and later northeastward, completing a loop.  This erratic
  motion was likely caused by interaction with equatorial westerlies.
  During this period central convection decreased in coverage and
  organization and unfavorable vertical shear increased.

     At 23/1200 UTC the depression's center was relocated to a position
  about 275 nm east of Samar Island.  Animated infrared imagery depicted
  a large, broad area of convection that was showing signs of increasing
  near the center of the low-level circulation.  However, Ondoy/28W never
  regained its intensity and continued to move generally north-
  northeastward.  JTWC issued their final warning on the system at 1800
  UTC on 24 November.   Ondoy/28W was located about 400 nm southeast of
  Okinawa and was moving northward at 21 kts.  The depression had by
  that time lost its tropical characteristics and was declared extra-
  tropical.  However, PAGASA was still classifying Ondoy as a tropical
  storm and issued warnings on the system until 25/1200 UTC when it was
  downgraded to a depression.

  C. Comparisons between JTWC and Other Centers

     JMA never estimated winds higher than 30 kts, which was the reason
  Tropical Storm 28W never received a name from the official WMO naming
  list.  This does not represent a significant difference as compared
  with JTWC, whose peak 1-min avg MSW for the storm was only 40 kts, and
  that for only one 6-hour period.   Neither did NMCC upgrade the system
  to tropical storm status.  PAGASA was the more liberal warning center
  with Ondoy/28W, treating it as a tropical storm for 4 1/2 days.  The
  peak 10-min avg MSW estimated by PAGASA was 40 kts from 22/0600 through
  25/0600 UTC.  Interestingly, PAGASA upped the intensity of Ondoy to
  40 kts twenty-four hours after JTWC had downgraded the system to a
  tropical depression.  A 10-min avg wind of 40 kts would correspond to
  1-min avg MSW of 45 kts.  I do not know if this discrepancy was based
  upon a differing interpretation of satellite imagery or if PAGASA was
  privy to some synoptic reports unavailable to JTWC and JMA.

  D. Damage and Casualties

     No reports of any damage or casualties resulting from Tropical Storm
  Ondoy/28W have been received.

                    Tropical Storm  (TC-29W / Pabling)
                             18 - 24 November

  Pabling: PAGASA name, is a Filipino nickname

  A. Storm Origins

     An area of convection had begun to organize around 0600 UTC on
  16 November approximately 200 nm northwest of the island of Borneo.
  Persistent convection was organizing around a developing LLCC.  A
  15/2204 UTC QuikScat pass had revealed the existence of a broad and
  elongated circulation while CIMSS analysis indicated fair outflow with
  weakening shear over the region.  The disturbance drifted westward 
  during the next two days with little change in organization.  At 0600
  UTC on the 18th the system was located about 280 nm northeast of 
  Singapore.  A surface analysis at 18/0000 UTC revealed a broad LLCC
  on the southern end of a northeast monsoon surge with persistent but
  still unorganized convection.  A SSM/I pass at 18/1122 UTC depicted
  a possible banding feature, therefore, JTWC issued a TCFA at 1700 UTC.
  The disturbance was located roughly 230 nm northeast of Singapore at
  the time.  JMA began classifying the system as a 30-kt depression at
  1800 UTC, an intensity which was maintained in their High Seas 
  Bulletins throughout the depression's history.

     By 19/0600 UTC the disturbance had begun to drift back toward the
  east--it was then located about 310 nm east-northeast of Singapore.
  A 19/0221 UTC SSM/I pass depicted a convective banding feature with
  the LLCC southeast of deep convection.  At 1700 UTC JTWC re-issued the
  TCFA for the system, which by then was located about 350 nm east-
  northeast of Singapore.  Deep convection had continued to cycle and
  was sheared to the northwest of the LLCC.  JTWC issued their first
  warning on Tropical Depression 29W at 20/0600 UTC with an initial
  intensity of 25 kts.  The depression was centered approximately 500 nm
  northeast of Singapore and was moving north-northeastward at 8 kts.
  At 1200 UTC an amended warning was issued which relocated TD-29W's
  center about 95 nm to the southeast of the original warning position.
  A 20/1055 UTC SSM/I pass had depicted a weak, exposed LLCC.  However,
  a QuikScat pass shortly afterward indicated a well-defined vortex
  with a 30-kt westerly wind component.   The depression was upgraded to
  Tropical Storm 29W at 0000 UTC on 21 November.  The cyclone's center
  at the time was located approximately 300 nm west-southwest of the
  southern tip of the island of Palawan, moving east-northeastward at
  4 kts.

  B. Track and Intensity History

     Tropical Storm 29W tracked east-northeastward through most of the
  21st, although by 1800 UTC its forward motion had slowed and it was
  drifting slowly northward.  A 21/1042 UTC SSM/I pass depicted a well-
  defined LLCC with a pronounced banding feature over the northeastern 
  quadrant.   The cyclone was being steered on its eastward track by 
  equatorial westerlies to the south.     JTWC never increased the MSW 
  above 35 kts, and no other warning center assigned tropical storm 
  status.  However, both KGWC and SAB were assigning CI numbers of 2.5, 
  so minimal tropical storm status seems realistic.  By 22/0600 UTC the 
  eastward motion had resumed with the center located approximately 
  220 nm north of Brunei.  Also, the system had entered PAGASA's AOR and
  had been christened Pabling.  At 1200 UTC Pabling/29W's center was 
  located about 110 nm west-southwest of Punta Baja Harbor on Palawan.  
  Satellite intensity estimates were still 35 kts, but SSM/I data 
  indicated that the LLCC was decoupled to the east of the deep 
  convection as the system had encountered increasing vertical shear.

     JTWC downgraded Tropical Storm Pabling/29W to a tropical depression
  at 23/0600 UTC when it was located about 40 nm west of the southern tip
  of Palawan Island.  Convection continued to be sheared to the west of
  the LLCC and JTWC issued the final warning on the system at 0600 UTC
  with the center just off the southern tip of Palawan Island.  The MSW
  was still estimated at 30 kts, and it is a little unusual for JTWC to
  finalize a NWP system until winds have dropped below the normal warning
  criteria of 25 kts or else a system has become extratropical.  However,
  the remnants of Pabling/29W were mentioned in the STWO issued at 0600
  UTC on 24 November.  Disorganized convection was still associated with
  the weak LLCC, but winds by that time were estimated at no higher than
  10 to 15 kts.

  C. Comparisons Between JTWC and Other Centers

     As noted above, JTWC was the only agency to classify Pabling/29W as
  a tropical storm, and a minimal one at that.   Both JMA and PAGASA
  carried the system as a 30-kt tropical depression for several days,
  which represents good agreement with JTWC's peak 1-min avg MSW estimate
  of 35 kts.    However, JMA also uses Dvorak T2.5 as the threshold for
  tropical storm intensity, so apparently they were not assigning CI
  numbers quite as high as some of the other agencies.

  D. Damage and Casualties

     No reports of damage or casualties resulting from Tropical Storm
  Pabling/29W have been received.

  E. Additional Discussion

     Mark Lander of the University of Guam posted an interesting
  discussion about the circulation features in the Southeast Asia/
  Northern Australia region during the time when Pabling/29W was active.
  Two monsoon troughs were present--one north of the equator and one to
  the south.  And as Mark writes, "tropical cyclones are popping out
  all over".  The westernmost system in each hemisphere--a depression in
  the South Indian Ocean (identified by JTWC as TC-04S) and Pabling/29W
  were moving eastward, while the easternmost systems--Ondoy/28W and a
  depression in the Arafura Sea (briefly identified as TC-03S by JTWC)
  were moving westward.  Mark points out that the situation was somewhat
  reminiscent of late 1996 when several tropical cyclones formed in each
  hemisphere along twin monsoon, or near-equatorial, troughs.  Tropical
  Storm Greg in December of that year moved on a very similar track to
  Pabling/29W, moving eastward at a very low latitude and making landfall
  in East Malaysia (on Borneo).  (NOTE:  The term "tropical cyclone" as
  used by Mark is to be understood in the generic sense of a system of
  any intensity, not in the more restrictive sense in which it is used
  in the Southern Hemisphere.)

                       Addendum to October Summary

     A few days after the October summary had been disseminated, I
  received an e-mail from Ms. Duong Lien Chau from Hydromet Service
  of Vietnam with additional information on the unnamed tropical
  depression which affected the country in October.  According to
  Ms. Duong, the depression made landfall very close to Tuy Hoa (13.1N,
  109.3E) with maximum sustained winds of 31 kts, gusting to 35 kts.
  The depression brought rainfall amounts of 100-200 mm for the central
  part of Vietnam with a few locations netting 200-300 mm.  However,
  no significant damage was reported due to the storm.

     I also received some information on this system from Roger Edson,
  who had reviewed some satellite imagery and also QuikScat data for
  the depression.  Roger noted that the depression was accompanied by
  a large monsoon-like cloud mass capable of producing copious amounts
  of precipitation.  QuikScat showed winds 30-35 kts, which also agreed
  with his estimate based on imagery.  Roger concluded that the system
  could have possibly been a minimal tropical storm.

     A special thanks to Ms. Duong and Roger for the information they


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

  Activity for November:  1 tropical cyclone of gale 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 November

     Climatologically, November is one of the more active months in the
  North Indian Ocean basin, having produced some intense hurricanes in
  the past.  However, November of 2001 was rather quiet, producing only
  one tropical cyclone which very briefly was a minimal tropical storm.
  This system was the fourth system in 2001 to be numbered by JTWC, but
  was the only one to occur in the Bay of Bengal, which is the half of
  the basin that normally sees about 2/3 to 3/4 of the tropical cyclone

  NOTE: Following the narrative for Tropical Cyclone 04B is a very brief
  addendum to the October summary.

                       Tropical Cyclone  (TC-04B)
                             9 - 12 November

     An area of convection developed in the southern Bay of Bengal
  in early November--on the 7th it was located about 150 nm east of
  Madras, India.  Deep convection was intermittent, but the broad
  cyclonic circulation was located under a ridge axis with favorable
  upper-level outflow.   A QuikScat pass at 08/1221 UTC indicated a
  weak but well-defined LLCC embedded in a broad trough which extended
  southwest to northeast.  A TRMM pass at 1100 UTC on 9 November
  indicated increasing organization of convection near the circulation
  center.  The MSW was estimated at 20-25 kts and JTWC upgraded the
  development potential to fair.  JTWC issued a TCFA at 1400 UTC on the
  10th when the disturbance was centered roughly 150 nm east-northeast
  of Madras.  The convection had expanded during the previous 12 hours,
  and synoptic data along the Indian coast indicated pressure falls
  associated with the offshore LOW.  The maximum winds were estimated
  at 25-30 kts and the system lay under a ridge axis with minimal shear
  and diffluent flow aloft.   A QuikScat pass around 1800 UTC indicated
  increased organization of the LLCC with the strongest winds located
  to the west and southwest of the center.

     JTWC issued their first warning on Tropical Cyclone 04B at 0000 UTC
  on the 11th.     The system was located just off the Orissa coast, 
  drifting northward at 3 kts.  Animated visible imagery indicated an
  exposed LLCC situated in a weakness in the subtropical ridge.  The
  cyclone was forecast to track slowly northward and make landfall in
  eastern India.  The second warning, issued at 11/1200 UTC, placed 
  the center of TC-04B approximately 275 nm northeast of Madras, moving
  northward at 5 kts.  The MSW of 30 kts was based on CI estimates of
  30 kts and synoptic data.  However, an amended warning was later issued
  upgrading the MSW to 35 kts based on a QuikScat pass at 1245 UTC.  The
  slight intensification trend was brief--at 12/0000 UTC the MSW was
  lowered back to 30 kts based on CI estimates of 25 kts and synoptic
  data indicating 25-30 kt winds.  Animated enhanced infrared imagery
  depicted intermittent bursts of deep convection decoupled well to the
  north of the poorly-defined LLCC.   Recent QuikScat data revealed that
  the gale-force winds in the western quadrant were weakening and that
  winds in the southern quadrant had dropped to 20 kts.  Tropical Cyclone
  04B had become a victim of strong southerly shear.  The 12/0000 UTC 
  warning was the final one issued by JTWC and placed the weakening 
  center about 350 nm northeast of Madras, moving northeastward at 6 kts.

                        Addendum to October Summary

     In the October summary I reported on a Bay of Bengal system for
  which JTWC did not issue any warnings, but which India had classified
  as a cyclonic storm (i.e., a tropical storm).   Roger Edson (at my
  request) also sent me his opinion on this system.  Roger indicates
  that he examined scatterometer data and multi-spectral satellite
  imagery, and in his opinion the system never reached a maximum
  intensity higher than 25 kts.   The center was always well-removed
  from the convection.


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

  Activity for November:  1 tropical depression **
                          1 tropical cyclone ++

  ** - treated as a minimal tropical storm by JTWC
  ++ - system formed east of 90E in the Australian Region

     The primary sources of information upon which the narrative is based
  are the warnings issued by the TCWC on La Reunion Island, part of Meteo
  France, which is the RSMC for the Southwest Indian Ocean basin.
  However, cyclones in this region are named by the sub-regional centres
  on Mauritius and Madagascar with longitude 55E being 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 implying a 10-min averaging period unless
  otherwise stated.   In the accompanying tracks 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. 

           Southwest Indian Ocean Tropical Activity for November

     Two tropical systems roamed Southwest Indian Ocean waters during
  November, both in the eastern portion of the basin.   A tropical
  disturbance, numbered 03 by La Reunion, briefly reached tropical
  depression status (10-min mean winds of 30 kts) on 21 November.  This
  system was treated as a minimal tropical storm by JTWC.  The other
  tropical system, Tropical Cyclone Bako, formed east of longitude 90E
  in the Australian Region where it was originally known as Bessi.  The
  complete history of Tropical Cyclone Bessi-Bako can be found in the
  section of this summary covering the Northwest Australia/Southeast
  Indian Ocean region.

                  Tropical Depression  (TC-04S / MFR #3)
                             15 - 23 November

     An area of convection developed on 14 November approximately 170 nm
  east-northeast of Diego Garcia in association with a developing LLCC.
  The convection was disorganized, but a 200-mb analysis indicated that
  the disturbance was located within a favorable environment for further
  development with low vertical shear and divergence aloft.  A QuikScat
  pass at 15/1248 UTC was the basis for relocating the disturbance to a
  position about 440 nm east of Diego Garcia.  Convection near the LLCC
  was continuing to cycle in intensity.  A special STWO issued by JTWC
  at 16/1600 UTC placed the system approximately 300 nm southeast of
  Diego Garcia.  The potential for development was upgraded to fair--the
  convection was persisting and the upper-level environment improving.
  Over the next couple of days the disturbance changed little in organ-
  ization while meandering about southeast of Diego Garcia.  La Reunion
  issued sporadic bulletins on the broad and diffuse system beginning
  at 1200 UTC on the 15th.

     At 19/1800 UTC JTWC relocated the LLCC to a point about 450 nm
  east-southeast of Diego Garcia and downgraded the potential for
  development to poor.  The system was moving south of the upper-level
  ridge axis into an area of northerly winds.  By 1100 UTC on the 20th
  the disturbance had moved farther to the east and was located roughly
  600 nm east-southeast of Diego Garcia.  The LLCC was located once more
  beneath the upper-level ridge axis in an environment of lower shear
  and enhanced outflow; therefore, the development potential was 
  re-upgraded to fair.    By 21/0300 UTC the LLCC had migrated to a 
  position approximately 675 nm east-southeast of Diego Garcia and had
  shown a marked improvement in its convective organization.    JTWC
  issued a TCFA, estimating the winds at 25-30 kts.   The first warning
  from JTWC on TC-04S was issued at 21/0600 UTC with an initial inten-
  sity of 30 kts.  At the same time MFR upgraded the disturbance to 
  tropical depression status with 10-min mean winds estimated at 30 kts.
  The depression's center was then located approximately 700 nm east-
  southeast of Diego Garcia.  Water vapor imagery depicted a large-
  amplitude trough approaching from the southwest.  Models indicated
  that a cut-off LOW would develop near the base of the trough which
  should prevent TC-04S from becoming embedded in the northwesterlies
  ahead of the trough and moving off to the southeast.

     At 1800 UTC the system was centered about 725 nm east-southeast of
  Diego Garcia.   JTWC upped the 1-min avg MSW to 35 kts based on CI 
  estimates of 30 and 35 kts.  The system was moving southeastward at
  4 kts, but a turn to the west was forecast.    MFR downgraded the 
  depression back to tropical disturbance status with 25-kt peak winds
  at 22/0600 UTC, although 30-kt winds were forecast to occur in
  isolated spots in the southern semicircle.  JTWC maintained the 35-kt
  MSW at 0600 UTC based on 35-kt winds depicted by a 22/0058 UTC QuikScat
  pass.   TC-04S was tracking very slowly to the south-southwest at this
  time, and by 1800 UTC the forecast turn to the west had occurred, the
  system being steered by a low to mid-level subtropical ridge.  The
  center was estimated to be about 630 nm east-southeast of Diego Garcia
  and moving westward at 10 kts.  JTWC reported the MSW at 30 kts based
  on CI estimates of 25 and 30 kts.  

     It is interesting to compare how the intensity forecast (as per the
  JTWC warnings) evolved on 21 and 22 November.    At 21/1800 UTC the 
  forecast called for no strengthening with dissipation by the end of
  the forecast period.    The 22/0600 UTC warning, however, forecast 
  modest strengthening while the 1800 UTC forecast called for slight
  weakening initially followed by static intensity through the remainder
  of the forecast period.   Despite the hints at some strengthening on 
  the 22nd, the intensity forecast included in the 21/1800 UTC warning 
  proved to be the one that verified.     By 23/0600 UTC the MSW had 
  dropped to 25 kts and JTWC issued its final warning on TC-04S with the
  weakening center located about 560 nm southeast of Diego Garcia.  Six
  hours later, La Reunion issued its final bulletin on the system.



  Activity for November:  2 tropical LOWs **
                          1 tropical cyclone ++

  ** - one system originated east of 135E and was very briefly treated
       as a minimal tropical storm by JTWC
  ++ - system later moved across 90E into the Southwest Indian Ocean

     The primary sources of information for Northwest Australia/Southeast
  Indian Ocean tropical cyclones are the warnings and bulletins issued by
  the TCWC at Perth, Western Australia, and Darwin, Northern Territory.
  References to sustained winds should be understood as being based on a
  10-minute averaging period unless otherwise noted.  Warnings issued by
  JTWC in Hawaii were the source of the 1-minute average MSW values given
  in the accompanying cyclone tracks file and were occasionally used for
  comparison purposes.

                Northwest Australia/Southeast Indian Ocean
                      Tropical Activity for November

     The Perth TCWC issued warnings on two tropical systems during the
  month of November.  The first was a tropical LOW early in the month
  which moved over waters west of Cocos Island.  The initial weak LOW
  actually originated just west of longitude 90E about 625 nm west-
  northwest of Cocos on 7 November.  It moved slowly east-southeastward,
  reaching a point 250 nm west of the island early on the 10th.  Perth
  issued gale warnings on the 10th in anticipation of the LOW's 
  developing into a tropical cyclone.  This did not happen, however, and
  the final warning was issued at 10/2200 UTC.  The residual LOW drifted
  back westward and was last mentioned on 13 November when located about
  500 nm west of Cocos Island.  JTWC did not issue any warnings on this
  system, although a TCFA was issued at 2000 UTC on 9 November.

     The other system was Tropical Cyclone Bessi which formed northwest
  of Cocos Island late in the month.   Bessi moved slowly southward,
  later turning westward and crossing longtidue 90E into the Southwest
  Indian Ocean basin where it received the name Bako.  Since the cyclone
  originated in Perth's AOR, it is covered in its entirety below.

     One other tropical LOW of note was one which moved from the Papua
  New Guinea area westward at a very low latitude, moving into the
  Arafura Sea and dissipating near the island of Timor.  Darwin never
  issued any warnings on the LOW, but JTWC briefly upgraded it to a
  minimal tropical storm.  Because of this, and because of the unusual
  track it followed, I have given it a little more coverage than I
  normally would give a weak system.  The history of this tropical LOW
  is contained in the section of this summary covering the Northeast
  Australia/Coral Sea region.

              Tropical Cyclone Bessi-Bako  (TC-05S / MFR #4)
                         25 November - 6 December

  A. Storm Origins

     A STWO issued by JTWC at 0900 UTC on 25 November noted that an area
  of convection had developed approximately 370 nm southwest of Sumatra
  and had persisted for over 12 hours.  Satellite imagery indicated an
  apparent LLCC associated with the convection while a 200-mb analysis 
  indicated that the disturbance lay in a region of marginal wind shear
  with a developing anticyclone aloft.   At 1800 UTC the system was
  located roughly 450 nm southwest of Sumatra and satellite imagery
  indicated increasing coverage of deep convection near the center.
  Upper-level conditions were still conducive for further intensifi-
  cation so JTWC upgraded the development potential to fair.   JTWC
  issued a TCFA at 26/0300 UTC, relocating the LLCC to a position about
  240 nm north-northwest of Cocos Island.  Winds were estimated at 20
  to 25 kts and deep convection near the center had continued to become
  better organized.  The Perth TCWC began issuing gale warnings for 
  the LOW in anticipation of its strengthening.  Some moderate shear
  affecting the system retarded its development slightly, making it
  necessary for JTWC to issue a second TCFA at 0300 UTC on the 27th.
  At 27/0600 UTC Perth upgraded the LOW to Tropical Cyclone Bessi,
  located approximately 350 nm northwest of Cocos Island, moving west
  at 7 kts.  JTWC also issued their first warning on TC-05S at the same
  time, estimating the intensity at 30 kts (based on CI estimates of
  30 and 35 kts).

  B. Track and Intensity History

     Bessi's initial westward track gradually curved to the south as a
  passing mid-latitude trough weakened the subtropical ridge.  The storm
  reached an initial peak intensity of 60 kts (10-min avg from Perth)
  at 0400 UTC on the 28th when centered approximately 375 nm west-
  northwest of Cocos Island, but thereafter began to weaken as it moved
  southward into a zone of significant vertical shear.  By 29/0300 UTC
  Perth had dropped the MSW to 40 kts as Bessi moved south-southeastward
  at 8 kts.  Satellite imagery revealed a partially-exposed LLCC with
  the associated deep convection displaced equatorward from the center.
  At 1800 UTC the cyclone was tracking south-southwestward, still in an
  environment of moderate shear, but by 0600 UTC on 30 November was 
  moving west at 13 kts.  Satellite intensity estimates were running
  around 35 kts, but there was a ship report of 45-kt winds.  Tropical
  Cyclone Bessi had moved west of longitude 90E by 30/0400 UTC, and at
  0600 UTC was renamed Tropical Storm Bako by Mauritius. 

     By the time the storm had entered the Southwest Indian Ocean basin,
  it had moved beneath an upper-level ridge axis into an area of reduced
  shear and convection responded by increasing once more.   At 1800 UTC
  Bessi-Bako was moving west-southwestward at 6 kts, and JTWC had
  increased the 1-min avg MSW back to 55 kts.  La Reunion soon followed
  suit, upping the 10-min avg MSW estimate to 50 kts at 0600 UTC on
  1 December and to 60 kts at 1800 UTC.  Bako's forward motion had
  slowed to only 2 kts, and a SSM/I pass shortly before 0600 UTC had
  depicted a 40-nm diameter eye feature.   By 02/0600 UTC the storm
  was moving south-southwestward at 4 kts.  A 40-nm banding eye feature
  was visible, and CI estimates had reached 65 kts.  JTWC estimated the
  1-min avg MSW at 65 kts, and at 1800 UTC increased it to 75 kts--the
  peak intensity for the storm.  La Reunion also upped the 10-min mean
  wind estimate to 65 kts, making Bako officially a tropical cyclone,
  (i.e., a hurricane).  Tropical Cyclone Bako at 1800 UTC was located
  approximately 700 nm west-southwest of Cocos Island and moving south-
  southeastward at 6 kts.  Satellite imagery revealed a ragged eye 20 nm
  in diameter.  The storm was located beneath an upper-level ridge with
  a poleward outflow channel evident.  The south-southeastward motion
  was due to the steering influence of a mid-level ridge to the storm's
  east and an approaching mid-latitude trough from the west.

     By 0600 UTC on 3 December Bako's forward motion had slowed once more
  and the cyclone was drifting southward at 2 kts.  Animated visible and
  infrared satellite imagery depicted a partially-exposed LLCC.  The La
  Reunion TCWC downgraded Bako to a severe tropical storm with 60-kt
  winds at 1200 UTC.   By 1800 UTC the storm was moving to the south-
  southeast at 5 kts and slowly weakening as it came under the influence
  of moderate vertical shear south of the upper-level ridge axis.  Bako
  had become quasi-stationary by 04/0600 UTC with a fully-exposed LLCC
  evident in satellite imagery.  MFR and JTWC lowered their intensity
  estimates to 40 kts (10-min avg) and 45 kts (1-min avg), respectively.
  A 200-mb analysis indicated that the storm was located beneath strong
  upper-level westerlies associated with a longwave trough over the South
  Indian Ocean.  Bako had weakened to minimal tropical storm intensity
  by 1800 UTC on the 4th, and was downgraded to a tropical depression
  by MFR at 05/0000 UTC.   JTWC issued their final warning at 0600 UTC,
  downgrading the system to a 30-kt depression located about 750 nm
  southwest of Cocos Island and drifting southwestward.    La Reunion
  declared Bako extratropical at 05/1200 UTC but continued to issue
  bulletins for another 24 hours as the LOW continued to move slowly
  southward.  A few gales were forecast for waters well south of the
  center through 06/1200 UTC.

  C. Comparisons Between Perth/La Reunion and JTWC

     Intensity estimates between JTWC and Perth were in reasonably good
  agreement, although the highest MSW estimated by JTWC during Bessi's
  initial peak was 55 kts (1-min avg), whereas Perth estimated a 10-min
  avg MSW of 60 kts--equivalent to a 1-min avg MSW of about 70 kts.
  After Bessi had crossed 90E and become Bako, the respective MSW values
  reported by La Reunion and JTWC were in very good agreement--JTWC's
  peak 1-min avg MSW of 75 kts being equivalent to MFR's peak 10-min avg
  MSW of 65 kts.  During the cyclone's decaying phase, the intensities
  reported by the two agencies were also in close agreement.

  D. Damage and Casualties

     Since Tropical Cyclone Bessi-Bako remained at sea far from any
  populated shores, no reports of damage or casualties have been



  Activity for November:  1 tropical LOW **
                          1 non-tropical LOW

  ** - system moved westward across 135E at a very low latitude

     The primary sources of information for Northeast Australia/Coral Sea
  tropical cyclones are the warnings and bulletins issued by the TCWCs
  at Darwin, Northern Territory, and Brisbane, Queensland.   References
  to sustained winds should be understood as being based on a 10-minute
  averaging period unless otherwise noted.   Warnings issued by JTWC in
  in Hawaii were the source of the 1-minute average MSW values given 
  in the accompanying cyclone tracks file and were occasionally used for
  comparison purposes.

                     Northeast Australia/Coral Sea
                     Tropical Activity for November

     There were no tropical cyclones in the Northeast Australia/Coral
  Sea region during November.   Around mid-month a weak tropical LOW
  formed near Port Moresby, Papua New Guinea, and moved westward along
  the southern coast of the island of New Guinea and into the Arafura
  Sea at a rather low latitude.  The LOW became better organized in the
  Arafura Sea and JTWC briefly upgraded it to a minimal tropical storm.
  For this reason and because of its unusual track, I have covered it
  in greater detail than I normally do for weak systems.  Late in the
  month the Brisbane TCWC issued gale warnings in association with a
  non-tropical LOW which formed about 250 nm east-northeast of Brisbane
  and moved generally eastward into the Fiji AOR.    Since this LOW
  possibly could have had some hybrid features, I included a track for
  it in the November cyclone tracks file.

                         Tropical LOW  (TC-03S)
                            15 - 24 November

     The daily TWO issued by Darwin on 15 November mentioned that a weak
  1006-mb LOW was located near Port Moresby, Papua New Guinea, and was
  forecast to move westward into the Arafura Sea.  JTWC issued a STWO at
  16/0200 UTC which noted that there had been a rapid increase in
  convective activity associated with the LOW, which by then was located
  just northeast of the Cape York Peninsula.  The LOW was near the axis
  of a sub-equatorial ridge under minimal vertical shear and with winds
  estimated at 15-20 kts (per JTWC).  By the 17th the LOW was situated
  over southern Papua New Guinea north of the Torres Strait.  Darwin gave
  the LOW a moderate chance of developing into a tropical cyclone after
  72 hours, and JTWC upgraded the development potential to fair.  Early
  on 18 November the system was still over southern Papua New Guinea
  about 370 nm north-northeast of Nhulunbuy in Australia's Northern

     By the 19th the LOW was over the Arafura Sea, moving westward.
  JTWC's STWO indicated that convection was sheared west of the well-
  defined, yet weak, circulation center.    The system was beneath the
  diffluent flow region of the sub-equatorial ridge--maximum winds were
  estimated at 20-25 kts.  The LOW continued moving westward on the 20th
  about 325 nm north of the Northern Territory coast, still in an
  environment of moderate shear.  At 1800 UTC, when JTWC issued their
  STWO, the center was estimated to be about 350 nm east-northeast of the
  Indonesian island of Timor.  JTWC issued a TCFA at 21/0000 UTC, placing
  the LOW's center approximately 200 nm east-northeast of Timor in the
  Banda Sea, or about 360 nm north of Darwin.   Convection was increasing
  in organization near the LLCC and shear was weak--the maximum winds
  were estimated at 25-30 kts.     Darwin also gave the LOW a moderate
  chance of developing into a cyclone after 48 hours.

     Up to this point Darwin and JTWC had been pretty much in agreement
  regarding the LOW's strength and its potential for development.
  However, that changed later on the 21st.  Darwin continued to regard
  the system as a tropical LOW without any gale warnings being issued.
  (The Australian warning centres normally issue gale warnings for a
  tropical LOW which is expected to develop into a tropical cyclone
  usually in advance of the actual appearance of gale-force winds.)
  JTWC, however, issued a warning at 21/0600 UTC upgrading the LOW to
  a 35-kt tropical cyclone (i.e., a tropical storm in U. S. terminology.)
  The JTWC warning placed the center in the Banda Sea east of Timor, or
  about 350 nm north-northwest of Darwin.  The warning intensity was
  based on CI estimates of 30 and 45 kts, i.e., Dvorak 2.0 and 3.0.
  The warning remarked that visible animated imagery depicted signifi-
  cant organization of convection over the vortex center during the past
  few hours.

     The 21/0600 UTC warning had also forecast a slight strengthening.
  This, however, did not materialize.  The second and final JTWC warning,
  issued at 1800 UTC, reduced the MSW to 25 kts.  CI estimates were 25
  to 30 kts, but synoptic reports indicated winds in the area of only
  15 kts.  Satellite animation depicted deep convection but no organized
  LLCC, and synoptic reports indicated surface pressures around 1012 mb.
  Darwin continued to mention the LOW through the 24th, but gave it only
  a low chance of developing into a tropical cyclone.

     The tropical LOW described in the above paragraphs was admittedly
  rather insignificant.  I gave it more detailed coverage than I normally
  do for such systems for two reasons:  the rarity of its degree of
  development in the Arafura and Banda seas at low latitudes, and the
  confusion that erupted over the system regarding the matter of nomen-
  clature, primarily due to its intensity hovering near that "magical" 
  man-made threshold of 34 kts.  Many students of tropical cyclone clima-
  tology would likely not regard the northern reaches of the Arafura Sea 
  and especially the Banda Sea as locations where tropical cyclones,
  especially intense ones, can occur, but there have been quite a few,
  albeit rare, destructive tropical cyclones recorded in those areas
  over the years.  For the Feature of the Month in the upcoming December
  summary, I plan to include a listing of destructive Indonesian tropical
  cyclones at very low-latitudes which Jeff Callaghan compiled.

     Regarding the issue of tropical system nomenclature, this particular
  system was just at that intensity level where by following the more
  liberal CI estimate or by taking an average, the MSW could be estimated
  at 35 kts, i.e., a tropical cyclone in accordance with Australian
  terminology; but by adhering to the more conservative CI estimate,
  the intensity would fall below gale-force in terms of both 1-min and
  10-min averages.    Darwin opted for the latter, which meant that
  they treated the system as simply a tropical LOW (the Australian TCWCs
  do not officially use the term "tropical depression") whereas JTWC
  opted to follow the more liberal intensity assessment.  In the Dvorak
  scale, T2.5 equates to gale-force in the 1-min avg system, but since
  a given Dvorak rating implies a range of intensities, and since the
  difference between a 1-min avg wind and a 10-min avg wind at the
  threshold of gale-force is only about 4 kts, the Japanese Meteoro-
  logical Agency equates a solid T2.5 to tropical storm intensity, even
  though they use a 10-min avg wind in their warnings.  This difference
  in intensity assessment, however slight, resulted in confusion when
  personnel on a U. S. naval ship related to the crew of an Australian
  naval ship that a tropical cyclone was in the vicinity.  In Australian
  terminology, the term "tropical cyclone" specifically implies 10-min
  avg winds exceeding gale force, whereas in U. S. terminology "tropical
  cyclone" is a generic term for tropical systems of all intensities.
  Furthermore, in the Southwest Indian Ocean basin, the term "tropical
  cyclone" implies a system with 10-min avg winds of 64 kts or greater
  (i.e., a hurricane).  In the author's opinion, of all the differences
  in terminology across the various oceanic basins, the multiple meanings
  attached to the basic term "tropical cyclone" probably leads to the
  most confusion.   (See the April, 2001, tropical cyclone summary for a
  description of official warning terminologies used by all the major
  warning centres.)


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

  Activity for November:  1 tropical cyclone of gale intensity

     Most of the information presented below was taken from operational
  warnings and advisories issued by the Fiji TCWC at Nadi.    References
  to sustained winds should be understood as being based on a 10-minute
  averaging period unless otherwise noted.  Warnings issued by JTWC/NPMOC
  in Hawaii were the source of the 1-minute average MSW values given in
  the accompanying cyclone tracks file and were occasionally used for
  comparison purposes.

     The report on Tropical Cyclone Trina was written by Alipate
  Waqaicelua, Chief Forecaster at the Nadi TCWC, with some additional
  information added by myself.  A very special thanks to Alipate for 
  preparing and sending the report to me (as well as the track for
  the cyclone.) 

               South Pacific Tropical Activity for November

     Last season the first South Pacific tropical cyclone did not make
  its appearance until February.  In contrast, the current season got
  underway quite early with the development of Tropical Cyclone Trina
  near Rarotonga in late November.  Trina remained weak, but did cause
  some significant damage on the island of Mangaia, mainly from flooding.

                Tropical Cyclone Trina  (TC-06P / TD-01F)
                       29 November - 3 December

  A. Storm Origins

     Trina was the first tropical cyclone of the 2001-2002 tropical
  cyclone season in RSMC Nadi's AOR.    It was first identified as a 
  sheared hybrid, developing off an upper-level cut-off LOW which 
  eventually spun its way to the surface to the west of Rarotonga on
  28 and 29 November.  The system was then slow-moving.  At 29/1800 UTC,
  Tropical Depression 01F was located only about 25 nm southwest of 
  Rarotonga over marginally warm SSTs of around 27 C and under strong 
  shear.  By 30/0000 UTC it had drifted closer to Rarotonga with deep 
  convection still displaced to between 30 and 120 nm southeast of the 
  exposed LLCC.  However, around 30/0230 UTC deep-layered convection was
  increasing in curvature and tops were steadily cooling.   With an 
  intense surface anticyclone to the south significantly enhancing the 
  gradient in the southwest quadrant, TD-01F was then named Tropical 
  Cyclone Trina at 30/0700 UTC when located about 45 nm south-southeast 
  of Rarotonga. 

  B. Track and Intensity History

     After being named, the exposed LLCC drifted under the upper-level
  trough axis and into a weak steering regime.  By December 01/0600 UTC,
  the LLCC had partly slipped under the deep convection.    However, 
  prevailing shear prevented any opportunities for intensification. 
  Therefore, for its entire life as a tropical cyclone, Trina maintained
  gale intensity.   Trina drifted slowly eastward on 30 November and
  1 December.  At 0000 UTC on 2 December the cyclone was downgraded to
  tropical depression status when located about 40 nm northwest of
  Mangaia.   The depression lingered in the area for another day or
  two and still produced a few gales in a boundary at some distance
  southwest of the center.

     The Southern Cooks, especially Rarotonga and Mangaia, were put under
  a Tropical Cyclone Alert in the first Special Weather Bulletin (SWB) 
  (updated every 6 hours) issued at 0809 UTC on 30 November.   Twelve 
  hours later, Rarotonga was placed under a Gale Warning while Mangaia
  was still under Alert.   At 0200 UTC on 1 December, Mangaia was placed
  under a Gale Warning as the cyclone drifted closer to the island.  Six
  hours later, only Mangaia was under a Gale Warning.  The final SWB for
  Mangaia was issued around 03/0335 UTC, after Trina had been downgraded
  to a tropical depression. 

  C. Comparisons Between Nadi and NPMOC

     NPMOC issued only three warnings for Tropical Cyclone Trina.  The
  first one, issued at 1200 UTC on 30 November, reported a 1-min avg
  MSW of 35 kts.  Fiji at this time was also reporting 35 kts for their
  10-min avg MSW estimate.  The remaining two NPMOC warnings estimated
  the intensity at 30 kts while Fiji still reported 35 kts, so the fore-
  casters at Nadi apparently saw Trina as a slightly stronger system
  than did NPMOC.

  D. Damage and Casualties

     Unconfirmed damage assessments reported that Mangaia sustained 
  inland and coastal flooding and erosion with 80% of root crops in one 
  area totally destroyed and about 20% of the livestock lost.  In Raro-
  tonga, especially over the southeastern side of the island, some 
  minimal damage was incurred from wind and surge.  The December mango 
  crop was destroyed.   A lady was very fortunate when a coconut tree 
  snapped and landed on her van as she was driving along the main road.
  The van consequently tipped over on the side.

     The above information came from Alipate's report.  I located some
  additional information on the website of the ReliefWeb.  Four days of
  heavy rains on Mangaia resulted in the worst flooding on the island
  in 50 years.  Parts of the island were under 2 metres of water.  Some
  of the press releases indicated that winds gusted above hurricane
  force--somewhat strong for a minimal tropical cyclone but certainly
  possible in strong thunderstorms.  About 90% of the taro crop was
  inundated and lost while other fruit crops fared badly also.  The
  latter press releases indicated that about 60% of the livestock on
  Mangaia--pigs, goats, chickens and horses--were drowned.  Fortunately,
  no human lives were apparently lost.


                              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
           November as an example:   nov01.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:  nov01.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>>>>

  NOTE:  The URL for Michael V. Padua's Typhoon 2000 website has

     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:>


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

     The URL is:>

     Also, TPC/NHC has available on its webpage nice "technicolor"
  tracking charts for the 2001 Atlantic and Eastern North Pacific
  tropical cyclones; also, preliminary storm reports for all the 2001
  Atlantic and Eastern North Pacific cyclones are now available, as
  well as track charts and reports on storms from earlier years.

     The URL is:>

     A special thanks to Michael Bath of Wollongbar, New South Wales,
  Australia, for assisting me with proofreading the summaries.

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


Document: summ0111.htm
Updated: 27th December 2006

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