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

                              OCTOBER, 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.)


                            OCTOBER HIGHLIGHTS
  --> Atlantic active with devastating Central American hurricane
  --> Both North Pacific basins also active with one super typhoon
  --> First Southern Hemisphere cyclone of the 2001-2002 season forms


               ***** Feature of the Month for October *****


     Last year on 30 August I received a copy of an e-mail from Roger
  Edson to Philippe Caroff at the La Reunion TCWC.  The message contained
  a letter sent to Roger by Tony Cristaldi, a forecaster and tropical
  cyclone enthusiast at the NWS office in Melbourne, Florida.  A few days
  earlier Tony had been downloading some additional images of the by now
  rather well-known midget cyclone which formed in the Mozambique Channel
  last June and was at its peak intensity on 21 June when the moon's
  shadow also crossed the Channel in the first total solar eclipse of
  the new millennium.  Tony indicated that he had pulled off about two
  days worth of POES passes on the days leading up to 21 June so that he
  could examine the structure of the cyclone during its formative stages.

     To quote Tony's e-mail: "I came upon a problem--the system I was
  looking at was NOT where it should have been.  The times and positions
  didn't match some data that I had already downloaded from the AFWIN and
  NRL Monterrey sites.     Instead, the cyclone remained SOUTH of the
  Channel and NEVER got all that close to Mozambique.  After scratching
  my head for a few minutes, I took a second look at one of the images
  in the HRPT reader.  Lo and behold!  I had typed in a FOUR instead of
  a SIX for the month when I pulled the data from SAA!  I was looking at
  data from APRIL 19-21!!"

     Tony further relates that upon discovering there was a midget
  cyclone on the exact same days two months earlier, he dug up my global
  summary for April, 2001, to read about it.  But nothing was there, nor
  in the monthly cyclone tracks file, since I knew nothing about the
  cyclone's existence.  Philippe's reply to Roger at least cleared up
  the mystery surrounding the cyclone, i.e., why no warnings were issued.
  Philippe indicates that he was certainly aware of the storm, but no
  warnings were issued because it formed outside of La Reunion's area of
  warning responsibility, the boundary being latitude 30 south.  Reunion
  did issue warnings on Tropical Cyclone Dera in March, 2001, until it
  began extratropical transition near 35S, but this was considered sort
  of "extra work".   Philippe related that personally he would like to
  see their AOR extended farther south, perhaps to 40S, and planned to
  bring this matter up at an upcoming regional meeting.

     Philippe's letter states that both the April and June cyclones were
  similar in that both formed in baroclinic environments.    The June
  midget formed from a wave along a cold front which became cut-off and
  migrated northward, whereas the precursor of the April cyclone exited
  alone from southeastern Africa.  Philippe indicates that he did not
  check the SSTs in April around 33S to 34S, but thinks it likely they
  were similar to the SSTs over which the June cyclone formed--around
  24-25C.  Both systems displayed some very similar cloud patterns when
  mature, but the April system was much longer-lived, remaining at a
  significant intensity for about four days, plus displaying some very
  significant diurnal fluctuations.

     A few weeks later Tony sent me a CD containing many satellite images
  of both the April and June cyclones, plus a track for the April system,
  both tabular and plotted.   In the meantime I had informed Dr. Karl
  Hoarau of Cergy-Pontoise University near Paris about the storm, so
  Karl set about the task of downloading satellite imagery covering the
  storm's history and deriving intensity estimates for the cyclone.  The
  track and intensities, based upon Tony's and Karl's inputs, follow
  the narrative.   Karl indicates that his 1-min avg MSW estimates repre-
  sent values less than the normal Dvorak numbers would yield in order to
  take into account the fact that the storm was not tropical all of the
  time, the rapid changes seen in the convection, and the high latitude
  of the track.

     The storm formed about 140 nm southeast of Durban, South Africa. 
  At 1200 UTC on 17 April a ship located near 29.2S, 35.0E reported a
  northerly sustained wind of 20 kts.  At the same time Durban (29.9S,
  30.8E) recorded a south-southwesterly wind of 15 kts.  Convection began
  to build during the morning of 18 April and a warm, elongated eye-like
  feature had formed by 1740 UTC.  However, convection was not all that
  deep--east of the "eye" the cloud top temperatures were in the range
  of -7 to -20 C.  On the 17th, while still basically extratropical,
  the system had moved slowly eastward, dropping a little to the south-
  east.  The center apparently made a small loop early on the 18th before
  moving a little more quickly south-southeastward for several hours.
  After around 1700 UTC the storm embarked on a very slow eastward track
  until early on the 19th.   Karl estimates that the cyclone reached its
  peak intensity of 55-60 kts (1-min avg) around 1700 UTC on the 19th.
  The Objective Dvorak T-number was 4.2 and the subjective T-number was
  4.0.    The CDO-feature appeared somewhat eroded but the "eye" was 
  faintly visible. 

     The storm jogged southward early on the 19th before resuming its
  slow east-southeastward motion several hundred miles south-southwest
  of southern Madagascar.   The convection became ragged and appeared to
  be northerly sheared early on 20 April but made a comeback later in
  the day.   Around 1200 UTC on 21 April the cyclone presented its
  most "tropical" appearance so far in its history.    (This being
  Tony's assessment of the system's character).  A large eye-feature was
  evident, open to the south and southeast.  The CDO extended well to the
  south, then southeastward in a reverse comma shape.  On the 21st the 
  storm took a jog to the north, then northwest, and later westward, 
  completing a loop which resembles a figure "8" lying on its side.  
  Karl's intensity log, which had decreased the MSW to 40 kts on the 
  evening of the 20th, shows an increase back to 45 kts on the morning 
  of the 21st to reflect this increased organization.  (Karl, however, 
  prefers to classify the system as extratropical even though there was 
  an increase in convection.)

     This increase in convection was temporary.  By 22/0000 UTC the cold
  cloud tops had warmed to the point that the cyclone was devoid of deep
  convection and was only a low-level swirl.  The storm was still moving
  west-southwestward early on the 22nd, but during the day recurved to
  the south-southeast and accelerated significantly.  Early on the 23rd
  the system crossed 40S and then underwent an extreme acceleration to
  the southeast.  By 0300 UTC on 24 April the cyclone was near 53.5S,
  57.5E and was being absorbed by an extratropical LOW.   Convection
  began to make a comeback around 1200 UTC on the 22nd and by early on
  the 23rd a ragged, banding-type eye had become visible.  Both Tony and
  Karl agree that at 23/1200 UTC, the cyclone's appearance was the most
  tropical-looking of its entire life.   Satellite imagery at 1126 UTC
  revealed what appeared to be a small eye (-14.8C) in the center of the
  CDO feature.  Karl's log increases the MSW back to 50 kts at this
  juncture.  However, whether or not the cyclone should be classified as
  a tropical cyclone is questionable.      As Karl points out in his
  discussion, the storm did present a tropical appearance around 1200 UTC
  on 23 April, but it was located at a rather high latitude (41S to 44S)
  and over SSTs of 16-18C.  Shortly after this secondary (or actually
  tertiary) peak in intensity, the storm encountered renewed shear and
  quickly weakened as it raced southeastward.

     I would like to extend a very special thanks to Tony Cristaldi, 
  Philippe Caroff, and Karl Hoarau for all the information they provided
  regarding this interesting storm system.

           Track of the Unnamed Southwest Indian Ocean Cyclone
                           17 - 24 April, 2001

   Date   Time   Lat    Lon     MSW               Comments
          (GMT)                1-min  

01 APR 17 0400  32.0 S  33.7 E       Extratropical LOW   
01 APR 17 1200  31.7 S  33.2 E
01 APR 17 1800  31.3 S  34.3 E
01 APR 17 2230  31.8 S  35.0 E  
01 APR 18 0000  31.9 S  35.4 E   25  
01 APR 18 0500  31.7 S  35.7 E   25  XT Low/1st Cb burst south of cntr
01 APR 18 1200  33.0 S  36.3 E   30  XT or Hyb/central Cb-partial CDO
01 APR 18 1730  33.3 S  36.5 E   45  Eye-like feature/little more trop.
01 APR 18 2200  33.2 S  36.9 E   45  Well-def eye/like TC embedded in XT
01 APR 19 0000  33.1 S  37.5 E   40  Cb diminishing north side of "eye"
01 APR 19 0500  33.5 S  38.1 E   40  CDO trying to re-organize
01 APR 19 1200  34.0 S  37.9 E   45  CDO better/"eye" barely visible  
01 APR 19 1700  34.1 S  38.1 E   60  CBO eroded N thru SE/"eye" faint
01 APR 19 2200  34.2 S  38.4 E   50  "Eye" open SW thru W/less tropical
01 APR 19 2330  34.3 S  38.8 E   50  
01 APR 20 0430  34.5 S  39.8 E   45  Central Cb ragged/sheared from NW
01 APR 20 1200  34.6 S  40.7 E   45  CDO better, more central
01 APR 20 1700  34.7 S  41.1 E   40  Cb shearing to SSE of center some
01 APR 20 2300  34.2 S  41.8 E   40  
01 APR 21 0400  34.9 S  41.5 E   40  CDO better, disp. to south of LLCC
01 APR 21 1200  34.4 S  40.6 E   45  More tropical-looking/large "eye"
01 APR 21 1630  34.7 S  40.0 E   45  Large "eye" open to south
01 APR 21 2300  35.1 S  38.8 E   30  System now void of deep Cb
01 APR 22 0400  35.2 S  38.5 E   25  Weak Cb east side
01 APR 22 1130  36.3 S  37.8 E   30  Central Cb re-dev. SE of center 
01 APR 22 2300  39.2 S  39.2 E   30  Cb ragged, disp. to south of LLCC
01 APR 23 0330  40.2 S  39.6 E   25  Ragged central convection
01 APR 23 0500  41.2 S  40.3 E   30  Banded, ragged eye
01 APR 23 1130  43.7 S  42.8 E   50  Most "tropical" appearance of all,
01 APR 23 1730  46.6 S  46.4 E   40    true eye in center of CDO
01 APR 23 2230  49.0 S  50.3 E   35  Accelerating rapidly SE-ward
01 APR 23 2330  49.9 S  51.2 E   30  Eye has collapsed
01 APR 24 0300  53.5 S  57.7 E   25  Being absorbed by large XT LOW
                           ACTIVITY BY BASINS

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

  Activity for October:  3 tropical storms
                         2 hurricanes

  NOTE:  Some 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 October prepared by the Hurricane Specialists which is
  available on TPC/NHC's website.

                  Atlantic Tropical Activity for October

     As will be obvious to most readers of these summaries, I am far
  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 basins 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 write-up for each storm.  I highly recommend that
  all readers go to NHC's website and read the reports.

     Five tropical cyclones developed during the month and all reached
  tropical storm intensity.    Two of these, Iris and Karen, became
  hurricanes with Iris reaching Category 4 intensity on the Saffir/
  Simpson scale.  The last system, Tropical Depression #15, was upgraded
  to Tropical Storm Michelle right around 0000 UTC on 1 November and 
  will be covered in the November summary.  All this activity represents
  an above-normal October--the average numbers of tropical storms, 
  hurricanes, and intense hurricanes (1950-2000) forming in the month 
  of October are 1.6, 1.1, and 0.3, respectively.

                        Hurricane Iris  (TC-11)
                             4 - 9 October

     Hurricane Iris was a very small tropical cyclone which intensified
  rapidly in the western Caribbean Sea into a severe Category 4 hurricane
  on the Saffir/Simpson scale on 8 October.   The core of Iris was very
  small--at one point the eye was only 3 nm in diameter and the radius
  of hurricane-force winds was only 10-15 nm--very small for a 120-kt
  hurricane.  During the morning of the 8th reconnaissance aircraft
  found three concentric eyewalls with radii of 3, 9, and 18 nm.  The
  innermost one soon collapsed, resulting in a temporary weakening of
  Iris, but with two others close in, the hurricane was soon intensifying
  again.  Iris reached an estimated peak intensity of 125 kts just before
  making landfall in southern Belize.  This was supported by a GPS drop
  which measured surface winds of 127 kts and objective T-numbers of
  T6.5 to T7.0 (127 to 140 kts) for about three hours.  Another GPS drop
  at 1900 UTC was reporting 132 kts when it failed at 46 m above the 

     Comparing the official "best track" (BT) with the operational track,
  only minor adjustments were made.  The BT starts the depression stage
  at 04/1200 UTC--six hours before the first advisory was issued--and
  also upgrades Iris to tropical storm intensity six hours before it was
  upgraded operationally.   A slight amount of confusion resulted when
  it was announced that if Iris regenerated in the Pacific, the name Iris
  would be retained, but when an Eastern Pacific storm did develop from
  Iris' remnants, a new number (15E) and name (Manuel) were applied.  I
  asked James Franklin about this and he clarified the issue:  NHC's
  operational procedures were changed a few years ago to the effect that
  if a tropical cyclone crossed Central America and warnings were issued
  continuously, then the original number and name would be retained.  
  However, if the original storm's LLCC dissipated and warnings were
  dropped, a new number and name would be applied if a cyclone developed
  subsequently in the Pacific.  (The same rules would apply for the much
  more rarer Pacific-to-Gulf of Mexico crossing.)  In the case of Iris,
  the hurricane's inner core did dissipate over Mexico, although some of 
  the leftover convection from Iris was instrumental in the formation of
  Tropical Storm Manuel in the Pacific.

     Hurricane Iris was very destructive to southern Belize, but since
  the storm was very small, the path of destruction was correspondingly
  narrow.  The government of Belize has reported a storm damage total of
  $66.2 million.    This figure comes from the official NHC report;
  a report located by the author on the Relief Web's website indicates
  that the damage to Belize was around $250 million.  (This report, dated
  4 January 2002, can be located at  Click on
  the Natural Disasters link, then the Hurricane Iris link.)   The eye
  of Hurricane Iris passed over Independence and Placencia, small towns
  around 130 km south of Belize City.  Eighty-five percent of the banana
  plantations were damaged, and corn, rice, plantain, mango, and cacao
  crops were also seriously affected.   Shrimp farms were also adversely
  impacted by Iris.

     The best estimate of the number of deaths resulting from Hurricane
  Iris stands at 31.  Three persons were killed in the Dominican Republic
  as the storm brushed that area, but the majority of the fatalities
  occurred on the boat M/V Wave Dancer, which capsized with 28 persons on
  board during the height of the storm while anchored at Big Creek.  At
  least 20 persons on board the boat are feared dead--all members of a
  diving club based in Richmond, Virginia, who were on a diving vacation
  off the coast of Belize.  There was also an unconfirmed report that 
  another boat, The Vendera, had capsized with people on board.  Finally,
  there were reports that eight persons had perished in flash flooding
  in Guatemala associated with Iris.

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

                       Tropical Storm Jerry  (TC-12)
                               6 - 8 October

     Tropical Storm Jerry was a short-lived, rather poorly-organized
  tropical cyclone which formed east of the Windward Islands and moved
  into the eastern Caribbean Sea where it dissipated a couple of days
  later.   Interestingly, the dissipation of Jerry was not anticipated.
  Most of the model guidance, as well as the NHC advisories, were calling
  for Jerry to reach hurricane intensity in two or three days.  Jerry's
  center passed just south of Barbados and very near St. Vincent, and
  gale-force winds were recorded on Martinique; however, there were no
  reports of damage or casualties associated with this tropical cyclone.

     The official TPC/NHC storm report on Tropical Storm Jerry, prepared
  by Richard Pasch and Daniel Brown, can be found at the following URL:>

                   Hurricane Karen  (TC-13 / STS #1)
                            10 - 15 October

     Hurricane Karen began as a strong extratropical LOW which caused
  wind gusts well above hurricane force on Bermuda.  The initial extra-
  tropical cyclone subsequently evolved into a subtropical storm and
  later tropical cyclone which became a Category 1 hurricane on the
  Saffir/Simpson scale.  Operationally, the system was not classified as
  a subtropical storm until 1800 UTC on 12 October, but in post-analysis
  it was determined that the parent LOW had acquired sufficient warm-
  core features to be classified as a subtropical storm by 12/0000 UTC
  when the cyclone was near Bermuda.    The NHC storm report on Karen
  includes a very detailed and interesting discussion of the thermo-
  dynamic and kinematic characteristics of the system during its
  evolution from extratropical to subtropical to tropical cyclone.  In
  the lower levels the system resembled a tropical cyclone while the
  upper levels were more typical of an extratropical cyclone.  There are
  presently no detailed, definitive criteria for classifying such systems
  as extratropical, subtropical, or tropical, and frequently it is
  impossible to make the best determination about a storm system's
  character and energetics until a careful study of all available data
  can be accomplished during post-storm analysis.

     By 0600 UTC on 13 October, temperature data from the Advanced Micro-
  wave Sounding Unit (AMSU) indicated that Subtropical Storm One had
  acquired enough warm-core characteristics to be classified as Tropical
  Storm Karen.  Karen was upgraded to a hurricane at 1800 UTC on the 13th
  and reached its peak intensity of 70 kts at 14/0600 UTC based on an
  objective Dvorak intensity estimate of 70 kts.  Thereafter, the storm
  weakened rapidly and made landfall in Nova Scotia as a 45-kt tropical
  storm on 15 October.

     Sustained winds to near hurricane force with gusts ranging from 78
  to 85 kts were officially recorded on Bermuda.    Additionally, the 
  cruise ship Nordic Empress reported a gust to 103 kts at 11/2317 UTC
  while anchored on the west side of the island.  Environmental pressures
  near Bermuda were higher than normal when the pre-Karen LOW approached
  and helped to create a very tight pressure gradient across the island.
  The extreme gust reported by the Nordic Empress was possibly related
  to strong downdrafts emanating from low-topped convection.

     The strong winds caused considerable tree and powerline damage on
  Bermuda.  At one point 23,000 persons were without power.  One cruise
  ship was set adrift when its mooring line snapped, and a dozen or so
  smaller boats broke loose from their moorings and either ran aground or
  were sunk.  Karen's rains were benefial to Nova Scotia and western
  Newfoundland where a drought had been in progress, but up to 150 mm of
  rain fell in twelve hours near Cape Race, resulting in the worst floods
  in 100 years in St. John's.  Wind gusts to 56 kts were reported in Nova
  Scotia but caused only minor tree damage.

     The official TPC/NHC storm report on Hurricane Karen, prepared by
  Stacy Stewart, can be found at the following URL:>

  NOTE:  The official "best track" for Karen begins at 11/0600 UTC, but
  gale warnings for the initial parent LOW were being issued on the 10th.
  The preliminary track for Karen included in the author's cyclone tracks
  file for October begins the track at 10/0000 UTC, based on information
  gleaned from TPC's High Seas Forecasts.

                      Tropical Storm Lorenzo  (TC-14)
                              25 - 31 October

     All things considered, Tropical Storm Lorenzo was the most
  insignificant named storm of the 2001 Atlantic hurricane season.  It
  remained at sea far from any populated shores and was the only storm
  not to intensify above minimal tropical storm intensity of 35 kts.
  Like several of the late-season tropical cyclones, Lorenzo was not
  tropical in origin--its roots lay in an upper-level trough over the
  eastern Atlantic.  The "best track" begins the tropical depression
  stage at 1200 UTC on 27 October.  In the cyclone tracks file for
  October, I traced the weak parent surface LOW back to 1800 UTC on the
  25th based on information contained in TPC's High Seas Forecasts.  For
  tropical cyclones originating from non-tropical systems, NHC normally
  begins the track at the point the system began to show signs of
  developing tropical characteristics, which makes sense for a tropical
  cyclone database.

     The official TPC/NHC storm report for Tropical Storm Lorenzo, 
  prepared by Miles Lawrence, can be found at the following URL:  >


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

  Activity for October:  1 tropical depression
                         2 tropical storms
                         2 hurricanes

            Eastern North Pacific Tropical Activity for October

     In terms of tropical storms, October, 2001, was fairly active
  with four named storms (plus one non-developing tropical depression).
  Two of these storms reached hurricane intensity.    For the period
  1971-2000, the average number of named storms and hurricanes for
  October has been 1.9 and 1.1, respectively.  The most active October
  in terms of tropical storms was in 1992 when five developed.  However,
  October, 1983, stands as the most active month of October on record
  in terms of net tropical cyclone activity.  Three intense hurricanes
  traversed Eastern Pacific waters during that month. 

     Since the official storm reports are now available on TPC/NHC's
  website, and since the storms were rather insignificant and did not
  affect land, I am not going to attempt to summarize them individually.
  Tropical Storm Lorena formed in early October south of the Mexican
  coast and at one point looked like it was going to make landfall, but
  shear increased and the storm dissipated west of Manzanillo.  Tropical
  Depression 14E formed several hundred miles southwest of the Baja
  California peninsula while Lorena was operating further east, but
  dissipated within 30 hours after the first advisory was issued.
  Tropical Storm Manuel formed from the remnants of Caribbean Hurricane 
  Iris and pursued a westerly and west-northwesterly track away from the 
  mainland.  Manuel intensified to 45 kts, weakened to a depression,
  then re-intensified, reaching a peak intensity of 50 kts on the 16th.
  It should be noted that Manuel did not form from the core circulation
  of Iris--that dissipated over Mexico--but rather developed in 
  association with some convection from Iris which had moved southward
  over Pacific waters.  Had the actual circulation of Iris reached the
  Pacific intact and re-intensified, it would have retained the name
  Iris.  Hurricanes Narda and Octave were twins--both formed in the same
  general area roughly 1000 nm southwest of Baja California, both reached
  a peak intensity of 75 kts, and both lasted for only four or five days
  as they pursued similar west-northwestward tracks.

     In the table below I have included the links to the official NHC
  reports for all the 2001 Eastern Pacific tropical cyclones as well
  as the name of the author of each report.  I highly recommend that
  readers go to NHC's website and read the reports.

 Cyclone                     Link                        Author(s)

 Adolph>     Stacy Stewart   
 Barbara>    Jack Beven
 Cosme>      James Franklin
 Erick>      Lixion Avila
 Dalila>     Miles Lawrence
 TD-06E>      Richard Pasch
 Flossie>    Stacy Stewart
 Gil>        Jack Beven
 Henriette>  Daniel Brown/
                                                         James Franklin 
 Ivo>        Lixion Avila
 Juliette>   Miles Lawrence/
                                                         Michelle Mainelli
 Kiko>       Richard Pasch
 Lorena>     Stacy Stewart
 TD-14E> Jack Beven
 Manuel>     James Franklin
 Narda>      Lixion Avila
 Octave>     Miles Lawrence

     Tropical cyclone activity was very minimal in the Central North
  Pacific region during 2001.  The Central Pacific Hurricane Center to
  my knowledge has not prepared any storm reports such as those by
  TPC/NHC, but a brief end-of-season summary can be found at the website
  for the CPHC:>

  Click on the link: Year End Summary


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

  Activity for October:  1 tropical depression **
                         2 typhoons
                         1 super typhoon

  ** - This system was treated as a tropical depression by JMA and
       some of the other Asian TCWCs, but not by JTWC

  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 October

     Tropical cyclone activity in the Northwest Pacific basin was down
  some from the level seen during August and September, but was probably
  about normal for the month.  Three tropical cyclones were named, and
  all three reached typhoon intensity.  Typhoon Krosa formed near the
  Marianas Islands, moved northwestward and executed a fairly smooth
  recurvature south of Japan.  Typhoon Haiyan formed in the Philippine
  Sea and recurved about midway between northern Taiwan and Okinawa.
  Both Krosa and Haiyan were typhoons of moderate intensity, but the
  third typhoon of the month, Podul, became an intense and long-lived
  super typhoon.  Podul formed near Pohnpei, farther east than most of
  the year's tropical cyclones, and followed a generally northward track
  well-removed from any populated areas except for a brush with the
  small island of Minami Tori Shima (Marcus Island).  Podul also was
  the first in a parade of tropical cyclones forming at very low
  latitudes during the latter months of 2001.

     One other system was classified as a tropical depression by JMA
  during October.  The initial disturbance can be traced back to an
  area of convection that formed on 17 October east of Palau.  During
  succeeding days the system moved westward, crossing Mindanao on the
  19th and 20th and emerging into the South China Sea.  JTWC upgraded
  the development potential to fair in a special STWO issued at 2100 UTC
  on 20 October.  A weak LLCC was present just west of Mindanao with
  some convection organizing around the center.    JMA classified the
  system as a weak depression in their High Seas Summary at 21/0000 UTC
  when the center was a couple hundred miles east of the Vietnamese
  coast.   JTWC issued a TCFA at 21/0300 UTC, noting that the disturbance
  was embedded in a broad expanse of convection associated with the
  monsoon trough.   The LOW continued moving westward at around 15 kts
  and had moved inland into Vietnam by 21/1800 UTC.   With the LLCC
  inland with no further chance of development, JTWC cancelled the TCFA
  at 22/0200 UTC.

     Even though the depression's winds were weak, it had precipitation
  power.  Torrential rains fell over portions of Vietnam's central
  provinces, leading to flash floods and river flooding.  A press report
  sent to the author by Huang Chunliang indicated that since August,
  floods and lightning had killed 361 people in Vietnam.    Earlier
  flooding in the Mekong Delta had claimed 322 lives, and 39 persons
  had died recently in the nine central provinces, likely due to the
  effects of the tropical depression.  Three of these deaths were due
  to lightning.  Total flood damages were estimated to be $66.6 million.

                    Typhoon Krosa  (TC-24W / TY 0120)
                             3 - 11 October

  Krosa: contributed by Cambodia, is the Cambodian word for crane (a
         type of bird)

  A. Storm Origins

     A persistent area of convection developed in early October near the
  Marianas Islands and on the 3rd was located just east of Guam.
  Animated satellite imagery depicted unorganized convection associated
  with a weak LLCC in the area.   As the day progressed the disturbance
  began to develop rather rapidly.  JTWC issued a TCFA at 1600 UTC as
  radar depicted a LLCC west of Rota on the southern edge of some deep
  convection and synoptic data indicated falling pressures in the region.
  A 200-mb analysis indicated that the system was located in an area of
  weak vertical shear with good outflow aloft.

     JTWC issued the first warning on Tropical Depression 24W at 1800 UTC
  with the center located approximately 40 nm north-northwest of Guam or
  about 30 nm west of Rota.    (A post-storm track indicates that it is 
  likely the system had reached depression status by 03/1200 UTC.)  Deep
  convection continued to increase and JTWC upgraded the depression to
  a tropical storm at 04/0000 UTC when the center was located about
  100 nm northwest of Guam or a like distance west-southwest of Saipan.
  JMA classified the system as a tropical depression at 0000 UTC, and at
  0600 UTC upgraded the cyclone to Tropical Storm Krosa while at the
  same time JTWC upped the MSW to 45 kts.

  B. Track and Intensity History

     Krosa tracked rather quickly northwestward away from the Marianas
  on 4 October as it was steered by a mid-level subtropical ridge to its
  northeast.    The storm also continued to intensify steadily in a
  favorable environment with water vapor imagery indicating the develop-
  ment of a poleward outflow channel.  By 1800 UTC JTWC had upped the
  MSW to 60 kts based on CI estimates of 55 and 65 kts.   JTWC upgraded
  Krosa to a 65-kt typhoon at 05/0000 UTC when it was located roughly
  400 nm west-northwest of Saipan.  Between 0600 and 1200 UTC the cyclone
  underwent rapid intensification, reaching its peak intensity of 105 kts
  at 1200 UTC (per JTWC's analysis) when located about 380 nm southwest
  of Iwo Jima.  Enhanced infrared satellite imagery and a recent SSM/I
  pass indicated that an intense convective ring had developed over the
  previous few hours, and animation indicated that the eyewall had
  contracted around a 14-nm diameter irregular eye.  Water vapor imagery
  revealed a pronounced poleward outflow channel extending from the
  system.  Gales extended outward about 180 nm from the center in the
  northern semicircle and about 115 nm to the south.  The radius of
  storm-force winds was estimated to be 60 nm.

     Typhoon Krosa tracked in an increasingly northward direction on the
  6th as it moved around the western edge of the subtropical ridge and by
  1800 UTC was moving north-northeastward.     The storm reached the
  westernmost point of its track at 06/0600 UTC when it was centered
  approximately 385 nm west-southwest of Iwo Jima.  The typhoon held its
  own, although there were some signs that it had weakened slightly:  the
  eye became less defined and convection weakened some.  JTWC reduced the
  intensity to 100 kts at 0000 UTC where it remained for 24 hours.
  Interestingly, the tracks from JMA and NMCC depict Krosa reaching its
  peak intensity (10-min avg) of 80 kts and 90 kts, respectively, at
  06/1200 UTC.  On 7 October JTWC decreased the MSW to 95 kts at 0000 UTC
  and to 90 kts at 0600 UTC where it remained through 1800 UTC.    It
  should be noted, however, that at least one CI estimate remained at
  102 kts through 1200 UTC.   By 1200 UTC both NMCC and JMA indicated
  some weakening of the typhoon.  At 07/0000 UTC Krosa was located about
  300 nm west of Iwo Jima, moving northeastward at 10 kts.  This fairly
  slow northeastward motion continued throughout the 7th.

     The storm continued to slowly weaken on the 8th with the intensity
  dropping to 75 kts by 0600 UTC (although one CI estimate remained at
  90 kts through 1200 UTC).  Typhoon Krosa passed approximately 275 nm
  north of Iwo Jima around 0900 UTC as it began to accelerate northeast-
  ward.  The cyclone's track gradually shifted more to the right, and by
  1800 UTC Krosa was racing east-northeastward at 27 kts.  The storm was
  also showing signs of extratropical transition as it encountered shear
  from the mid-latitude westerlies.  JTWC issued their final warning on
  Krosa at 09/0600 UTC, downgrading it to a 55-kt extratropical LOW
  located about 575 nm east-southeast of Tokyo or about 650 nm south-
  southeast of the Kuril Islands.  The system was developing frontal
  features as it moved further into a baroclinic zone.  NMCC also dropped
  the storm at 0600 UTC, but JMA carried it through two more warning
  cycles before declaring Krosa extratropical at 1800 UTC.  The potent
  extratropical storm continued rapidly east-northeastward, crossing the
  Dateline late on the 10th, and at 11/0000 UTC was still generating
  60-kt winds well south of the Aleutian Islands.

  C. Comparisons Between JTWC and Other Centers

     The MSW estimates from NMCC and JMA compared rather well with those
  from JTWC (after adjusting for the different averaging times) for most
  of Typhoon Krosa's history.  NMCC's estimated peak intensity of 90 kts
  compares very well with JTWC's peak MSW of 105 kts.  JMA's peak of
  80 kts is a little lower, but still in fairly good agreement.  As noted
  above, the interesting thing is that both the Asian TCWC's time of
  peak intensity for Krosa was shifted later than JTWC's.  JTWC's peak
  of 105 kts was from 05/1200 through 06/0000 UTC, JMA's peak intensity
  of 80 kts occurred from 06/1200 through 07/1200 UTC, and NMCC estimated
  their peak of 90 kts from 06/1200 through 07/0600 UTC.  The minimum
  central pressure estimated by JMA was 950 mb from 06/1200 through
  07/1200 UTC.

  D. Damage and Casualties

     No reports of damage or casualties resulting from Typhoon Krosa have
  been received.

                Typhoon Haiyan  (TC-25W / TY 0121 / Maring)
                               11 - 19 October

  Haiyan: contributed by China, is the name of a bird--the petrel

  A. Storm Origins

     On 7 October a persistent area of convection was noted deep in the
  tropics far to the south-southwest of Guam.  Animated satellite imagery
  depicted organized convection associated with a weak LLCC.  The system
  remained quasi-stationary on the 8th, but by the 9th had moved north-
  westward to a position about 100 nm southeast of Yap.  Convection had
  decreased some, but a 200-mb analysis indicated that the disturbance
  lay beneath diffluent easterlies associated with a sub-equatorial 
  ridge.    At 10/0600 UTC the system was relocated to a point about 
  275 nm northeast of Yap.  Convection was scattered, but by 1400 UTC 
  deep convection was seen to be increasing so JTWC upgraded the develop-
  ment potential to fair.

     The disturbance was relocated significantly to the northwest at
  11/0600 UTC to a position approximately 510 nm northwest of Yap.  The
  system's organization was continuing to improve in a region of weak
  vertical shear and good outflow.  Also at 0600 UTC, PAGASA initiated
  warnings on the system, naming it Tropical Depression Maring (a
  Filipino nickname) with 30-kt winds.  (Although JTWC did not issue the
  first warning until 1200 UTC, a post-storm track begins Maring/25W as
  a depression at 0600 UTC.)  JTWC issued a TCFA at 0700 UTC, followed
  at 1200 UTC by the first warning on Tropical Depression 25W, located
  approximately 470 nm east of northern Luzon.  The MSW was estimated
  at 25 kts and the depression was moving west-northwestward at 16 kts.
  Deep convection was erupting on the northern edge of the LLCC.

     JMA classified the system as a 30-kt tropical depression at 1800
  UTC.  JTWC's MSW remained at 25 kts based on CI estimates of 25 and
  35 kts plus synoptic reports.  JTWC upped the intensity to 30 kts at
  12/0000 UTC and to tropical storm status at 0600 UTC.   Maring's
  rather rapid west-northwestward motion had come to a halt--the cyclone
  was by this time moving northwestward at only 3 kts.   By 1800 UTC
  the available CI estimates were all 35 kts so JMA upgraded Maring/25W
  to Tropical Storm Haiyan with 35-kt winds (10-min avg).  JTWC's 1-min
  avg MSW was also still reported as 35 kts in the 1800 UTC warning.

  B. Track and Intensity History

     Tropical Storm Haiyan moved little on 13 October.  The cyclone
  remained quasi-stationary most of the day roughly 450 nm east of
  the northeastern tip of Luzon as it slowly strengthened.  JTWC upped
  the MSW to 45 kts at 0000 UTC and to 50 kts at 1200 UTC as animated
  visible satellite imagery depicted building deep convection over the
  LLCC.  By late in the day Haiyan was drifting northward at 3 kts in
  a weakened ridge flow pattern of the subtropical ridge.  A SSM/I pass
  during the (local) morning resulted in a 40-nm southward adjustment in
  the storm's position.  JTWC upgraded Haiyan to typhoon status at
  14/0000 UTC based on current intensity estimates of 45 and 55 kts and
  synoptic reports.  Satellite imagery indicated that the southwest
  monsoonal flow out of the Philippine Sea was enhancing the banding
  features and expanding the stronger winds over the eastern semicircle.
  By 0600 UTC Haiyan had turned to a slightly faster north-northwestward
  track about 500 nm east-southeast of Taipei.  Satellite intensity
  estimates had reached typhoon force by 1200 UTC and the MSW was bumped
  up to 70 kts.  A 14/0944 UTC TRMM pass had indicated that an eye was
  forming under extensive deep convection.  At 1800 UTC Haiyan's center
  was located about 265 nm south of Okinawa, and the storm's heading had
  turned to the west-northwest as the subtropical ridge strengthened
  slightly following the passage of a shortwave trough to the north.
  JTWC increased the MSW slightly to 75 kts, and NMCC and PAGASA both
  upgraded Haiyan to typhoon status.  (JMA did not upgrade the storm
  for another 24 hours.)

     During the 15th Typhoon Haiyan tracked initially westward and west-
  northwestward, but by 1800 UTC the storm had turned to the northwest.
  The mid-level ridge to the north was being weakened by the approach
  of a mid-latitude trough from the west.  JTWC gradually increased the
  MSW to the peak for the storm of 90 kts at 1800 UTC.  Satellite
  intensity estimates had reached 90 kts by this time and a ragged eye
  was visible.  Haiyan was located at 1800 UTC about 200 nm southwest of
  Okinawa, moving northwestward at 10 kts.  Gales covered an area almost
  400 nm in diameter, and 50-kt winds extended outward 80 nm from the
  center.  The forecast northward turn became reality on 16 October.
  At 0600 UTC the typhoon was moving northward, and by 1800 UTC Haiyan
  had passed north of the subtropical ridge axis and was trekking north-
  eastward under the steering influence of the mid-level ridge to the
  east.  Although there were a couple of CI estimates of 102 kts (T5.5),
  JTWC did not raise their MSW estimate above 90 kts.  At 1800 UTC Haiyan
  was located about 100 nm west of Okinawa and was beginning to show
  signs of extratropical transition--the MSW had been lowered to 75 kts
  by this time.

     On the 17th Haiyan began to get caught up more and more in the mid-
  latitude westerlies.   At 17/0000 UTC the storm was located about 80 nm
  northwest of Okinawa and moving northeastward at 11 kts.  By 1800 UTC
  the center was approximately 230 nm southeast of Sasebo, or 500 nm
  southwest of Tokyo, and scooting east-northeastward at 23 kts.  The
  intensity continued to slowly decline as the day progressed, although
  infrared imagery indicated some re-development of deep convection
  during the (local) night.  At 1800 UTC JTWC downgraded Haiyan to a
  60-kt extratropical storm and issued their final warning.  JMA carried
  the cyclone as a tropical storm for another twelve hours, then declared
  Haiyan to be extratropical at 18/1200 UTC.  The remnant extratropical
  gale continued moving eastward, and at 19/1800 UTC was still generating
  35-kt winds about 950 nm east of Tokyo.  However, I was unable to find
  any further references to the system in JMA's High Seas Warnings, so
  presumably it weakened thereafter or else was absorbed by another

  C. Comparisons Between JTWC and Other Centers

     Intensity estimates between JMA and JTWC, after allowing for the
  different averaging periods, were in good agreement during the early
  stages of Haiyan's life when the storm was intensifying, and again
  during the rather rapid decaying phase.  JMA's peak 10-min avg MSW
  of 70 kts was a little low compared to JTWC's 90-kt peak MSW, but
  not unusually so.   NMCC's peak 10-min avg MSW estimate of 80 kts
  was in excellent agreement with JTWC's peak intensity.  PAGASA had
  reached 70 kts when Haiyan exited its AOR after 16/0000 UTC; however,
  this was during the time of the storm's peak per the other centers.
  CWBT and HKO estimated the storm's intensity (10-min avg) at 70 and
  75 kts, respectively, during the time that Haiyan was within their
  AORs.  The minimum central pressure estimated by JMA was 960 mb from
  16/0000 through 16/1800 UTC.

  D. Meteorological Observations

     I received a few rainfall reports from Huang Chunliang which had
  been sent to him by Chun-Chieh Wu of the National Taiwan University.
  These represent storm totals for the period 14/1600 UTC through
  16/1400 UTC for several stations on Taiwan:

            Station                        Rainfall (mm)

       Neo-Tsu, Hsinchu County                 322
       Anpu, Chutzhu                           234
       Tung-Hou, Taipei County                 223
       Ta-Chi, Taoyuan County                  214
       Kuang-Wu, Miaoli County                 185
       Da-Cho-C, Ilan County                   160

  E. Damage and Casualties

     No reports of damage or deaths resulting from Typhoon Haiyan/Maring
  have been received.

                  Super Typhoon Podul  (TC-26W / TY 0122)
                              18 - 29 October

  Podul: contributed by DPR Korea (North Korea), is the Korean name for
         the willow tree

  A. Storm Origins

     On 16 October a persistent area of convection was located deep in
  the tropics near Pohnpei.     Animated visible and infrared imagery
  indicated disorganized convection associated with a weak LLCC.  CIMSS
  analysis indicated fair outflow and weak to moderate vertical shear.
  Little change was noted on the 17th, except that the area of convection
  shifted about 120 nm to the south.  At 1200 UTC JTWC upgraded the
  potential for development to fair.  Deep convection was becoming better
  organized and a CIMSS analysis indicated that outflow was improving and
  shear was lessening over the region.    JTWC issued a TCFA at 2200 UTC
  after a considerable increase in the coverage of deep convection had
  been observed.  Also, a 17/1920 UTC QuikScat pass had indicated a LLCC
  situated over a surface trough just south of Pohnpei.

     JMA was the first warning agency to classify the developing cyclone
  as a tropical depression.  At 18/0000 UTC JMA located a 30-kt tropical
  depression slightly over 100 nm southwest of Pohnpei.   JTWC re-issued
  the TCFA at 2200 UTC followed by the first warning on Tropical
  Depression 26W at 19/0000 UTC.   (A post-storm track retroactively
  identifies the system as a depression at 18/1800 UTC.)  The center of
  TD-26W was located approximately 150 nm west-southwest of Pohnpei or
  about 270 nm east-southeast of Chuuk.  The warning intensity of 30 kts
  was based on CI estimates of 25 and 30 kts.  The partially-exposed LLCC
  was decoupled to the east of the deep convection.

     By 1200 UTC CI estimates were 30 and 35 kts, so JTWC upgraded the
  depression to tropical storm status, still pretty much in the same
  location.  A 19/0754 UTC SSM/I pass had revealed a partially-exposed
  center to the northeast of the nearest deep convection.  However, more
  recent enhanced infrared imagery depicted deep convection building over
  the LLCC.  Organization had improved by 20/0000 UTC, and with CI
  estimates of 35 and 45 kts, JTWC increased the MSW to 45 kts.  At the
  same time, JMA upgraded the cyclone to tropical storm status, assigning
  the name Podul.  Tropical Storm Podul was then located about 250 nm
  east of Chuuk, moving northward at 4 kts.

  B. Track and Intensity History

     Podul's intensity remained pegged at 45 kts for about 18 hours on
  20 October, but deep convection continued to increase and organize
  near the system's center.  JTWC upped the MSW to 55 kts at 1800 UTC
  and to typhoon intensity at 21/0000 UTC when Podul was centered about
  260 nm north-northwest of Pohnpei or roughly 700 nm east of Guam.
  The typhoon continued to trek toward the north as a weakness in the
  subtropical ridge allowed a near-equatorial ridge south and east of
  the system to exert a steering influence on Podul.  Intensification
  of the cyclone proceeded at a rather slow rate.  The MSW was increased
  to 75 kts at 21/1200 UTC and remained there for 18 hours.  NMCC and
  JMA both upgraded Podul to typhoon status at 22/0000 UTC.

     Typhoon Podul plodded northward on 22 October, shifting to a north-
  northeastward track late in the day.  The primary steering mechanism
  remained a mid-level near-equatorial ridge southeast of the storm, but
  a cutoff LOW to the northeast apparently was the factor causing the
  northeastward jog in Podul's track.  Podul continued its slow intensi-
  fication with winds reaching 90 kts by 1200 UTC.  A 22/1117 UTC SSM/I
  pass indicated a developing banding eye feature, while animated water
  vapor imagery revealed favorable conditions aloft with dual outflow
  channels.  The northeastward motion continued early on the 23rd, but
  by 1200 UTC had become north-northwesterly as a major shortwave ridge
  moving off Japan and a building mid-level peripheral ridge helped
  to provide a more northwestward track while the cutoff LOW filled and
  lifted out to the northeast.  JTWC increased the MSW to 100 kts at
  23/0000 UTC and steady intensification continued throughout the day.
  Winds were upped to 115 kts at 0600 UTC as satellite imagery indicated
  that the eyewall had contracted around a cloud-free eye.  By 1800 UTC
  Dvorak numbers had reached T7.0 from SAB, JTWC and KGWC, therefore,
  Podul was upgraded to the season's second super typhoon with 135-kt
  winds, located approximately 550 nm west-southwest of Wake Island.
  The storm was then moving northwestward at 4 kts, but was forecast to
  recurve to the north and northeast as a mid-latitude trough approached
  from the northwest.

     Super Typhoon Podul's slow northwestward trek continued on
  24 October, becoming slightly west-northwestward as the day progressed.
  The storm intensified further with the estimated MSW reaching 140 kts
  at 0600 UTC.  Satellite imagery revealed that Podul underwent a
  concentric eyewall cycle on the 24th--by 0600 UTC the eye diameter had
  expanded slightly to 24 nm.  Gales extended outward 170 nm from the
  center to the southwest and out 155 nm in the northern semicircle.
  The radius of 50-kt winds was estimated to be around 50-60 nm.  JTWC
  lowered the intensity to 130 kts for a 12-hour period beginning at
  25/0000 UTC but bumped it back up to 140 kts at 1200 UTC.  The eye
  diameter had increased to 30 nm by 25/0000 UTC and storm-force winds
  extended outward 80 nm from the center.  Podul maintained the 140-kt 
  intensity for 24 hours the second round.  During this period JMA and 
  NMCC both estimated their peak intensities of 100 and 120 kts, 
  respectively, while JMA estimated a minimum CP of 925 mb for the 
  typhoon's history.

     By 1800 UTC on the 25th Podul's motion had become northerly as
  the mid-latitude trough east of Japan continued to deepen and weaken
  the subtropical ridge.  The cyclone at this time was located about
  500 nm east of the northernmost Marianas Islands, and this represents
  the westernmost point in Podul's track.  Although satellite intensity
  estimates were still 140 kts at 26/1200 UTC, JTWC lowered the MSW to
  130 kts as the storm began to show signs of weakening.   Enhanced
  infrared imagery revealed cirrus streaming northeastward and a decrease
  in convection in the southwestern quadrant.  Even though still a super
  typhoon, Podul was showing the first hints of extratropical transition.
  By 1800 UTC Podul was located approximately 700 nm northwest of Wake
  Island and was moving north-northeastward at 22 kts.  JTWC decreased
  the MSW to 120 kts, thus ending Podul's reign as a super typhoon.  
  Podul had maintained super typhoon intensity (MSW 130 kts or higher) 
  for 72 hours, making it the longest-lived super typhoon since Keith in
  November of 1997 which was a super typhoon for 3.5 days.  According to
  Mark Lander, Super Typhoon Joan just a month earlier in October, 1997,
  holds the record for the longest continuous period of 130+ kt winds.  
  Joan maintained super typhoon status for 4.5 days, peaking at 160 kts.

     JTWC reduced the MSW to 100 kts at 27/0000 UTC, noting that animated
  satellite imagery indicated dry air entrainment and cold air advection
  in the southwestern quadrant.  As the day progressed Podul continued
  to accelerate north-northeastward and weaken.  By 1800 UTC JTWC judged
  the system to have completed extratropical transition and issued their
  final warning, locating the center south of the Kamchatka Peninsula
  approximately 1000 nm east of Japan and racing north-northeastward at
  32 kts.  Winds were still at typhoon strength, however, and JMA also
  was still classifying Podul as a typhoon.    JMA continued to issue
  warnings on Podul as a tropical storm through 28/0600 UTC, declaring
  the system extratropical at 1200 UTC.  The remnant extratropical LOW
  subsequently turned eastward and weakened--by 29/0600 UTC it was a
  996-mb LOW well south of the Aleutians, just west of the Dateline.

  C. Comparisons Between JTWC and Other Centers

     NMCC's peak 10-min avg MSW of 120 kts agrees very well with JTWC's
  estimated 140-kt peak intensity.  NMCC maintained an intensity of
  110 kts from 24/0600 through 26/1800 UTC, closely matching JTWC's
  period of super typhoon intensity for Podul.  JMA's estimated peak
  10-min avg MSW of 100 kts was reached briefly at 24/0000 UTC, and
  again from 25/1200 through 26/0600 UTC.   JMA's estimated 10-min avg
  MSW remained at 90 kts or higher from 23/1200 through 26/1800 UTC.
  The minimum central pressure estimated by JMA was 925 mb from 25/1200
  through 26/0600 UTC.

  D. Meteorological Observations

     The only observations I have available came from the small island of
  Minami Tori Shima (also known as Marcus Island).  These were obtained
  by Rich Henning.  At first it appeared that the intense typhoon might
  pass directly over the small island, but the center appeared to pass
  just to the east.  The lowest pressure reported was 967 mb at 1000 UTC
  on 26 October while the peak sustained wind was 44 kts at 0900 UTC.
  Winds exceeded gale force from 0300 through 1200 UTC, coming initially
  from the east-northeast and veering around to the northwest as the
  center passed by.

  E. Damage and Casualties

     Even though Podul was a very intense typhoon, other than the brush
  with Minami Tori Shima, it remained well away from any land areas.  No
  reports of damage or casualties have been received.


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

  Activity for October:  2 tropical cyclones of gale intensity **

  ** - One of these was classified as a cyclonic storm by IMD only

  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 October

     Two weak tropical cyclonic systems were tracked in the North Indian
  Ocean basin during October.  The first one, in the Arabian Sea, was
  designated as Tropical Cyclone 03A by JTWC and briefly reached minimal
  tropical storm intensity.  The second system developed in the Bay of
  Bengal and moved westward into southeastern India.  JTWC did not issue
  warnings on this disturbance, but IMD classified it as a cyclonic storm
  (i.e., a tropical storm).

                        Tropical Cyclone  (TC-03A)
                              9 - 10 October

     An area of convection developed on 7 October about 100 nm west-
  southwest of Bombay.  A weak LLCC which had tracked westward off the
  coast of India was associated with the convection, which was increasing
  in organization.  JTWC upgraded the development potential to fair at
  0500 UTC on the 8th, noting that convection was continuing to increase
  and that the disturbance was located in an area of fairly weak vertical
  shear with good outflow aloft.  However, a 08/1625 SSM/I pass failed to
  indicate any significant organization.   A TCFA was issued at 0300 UTC
  on the 9th.  Early morning visible satellite imagery and a 09/0055 UTC
  QuikScat pass indicated that a LLCC had developed beneath an intense
  mid-tropospheric cyclone with deep convection and the strongest winds
  in the northern quadrant.   The first warning on TC-03A was issued at
  09/0600 UTC with the initial intensity estimated at 30 kts.  Visible
  satellite imagery indicated the development of a banding cloud feature
  in the western semicircle.  A 200-mb analysis indicated diffluent flow
  extending over the region.

     JTWC increased the MSW to 35 kts at 09/1200 UTC.  The cyclone's
  center was located approximately 250 nm west of Bombay or about 370 nm
  south of Karachi, Pakistan, tracking west-northwestward at 7 kts as
  it was steered by a mid-level ridge anchored over the northeastern
  Arabian Sea.  Some recent microwave images depicted convective bands
  surrounding the LLCC and 37 GHz data from a 09/0913 UTC TRMM pass
  indicated that the low-level convection was most intense on the
  northern side in convergent flow.     The intensification trend for
  TC-03A, however, was quite brief.  At 1800 UTC, even though Dvorak CI
  estimates were still 35 kts, a QuikScat pass revealed peak winds of
  30 kts and it was felt that the QuikScat winds were more representative
  and in line with the current imagery trend.   Also, deep convection had
  dissipated over the LLCC, so the MSW was lowered back to 30 kts.

     The cyclone continued to slowly weaken as it drifted to the west-
  northwest across the Arabian Sea.  Entrainment of dry air from the 
  north was another inhibiting factor in the system's demise.  By 10/0600
  UTC the LLCC had decoupled from the deep convection farther north and 
  the MSW was lowered to 25 kts.  The final JTWC warning was issued at 
  1200 UTC with the exposed, convection-free LLCC located about 400 nm 
  south of Karachi, drifting slowly northward.  Re-intensification was 
  not considered likely given the unfavorable upper-level conditions and
  the dry air environment into which the system was moving.  (NOTE:  I
  was unable to obtain any bulletins or outlooks from IMD on the 10th
  and 11th, so I do not know if that agency ever classified TC-03A as
  a cyclonic storm.  IMD's Tropical Weather Outlook issued at 09/0711
  UTC referred to the system as a depression.)

                       Bay of Bengal Cyclonic Storm
                             15 - 16 October

     An area of convection developed in the Bay of Bengal about 325 nm
  south-southwest of Cuttack, India, on 13 October.  Synoptic data
  revealed a broad LLCC beneath the convection, and a 200-mb analysis
  indicated that the subtropical ridge extended over the region.  The
  system drifted westward on the 14th with little change in intensity.
  Late on the 14th the LOW seemed to be getting better organized, so
  JTWC upgraded the development potential to fair.  Enhanced infrared
  and early morning visible imagery on the 15th indicated a significant
  improvement in the convective organization of the system, so JTWC
  issued a TCFA at 15/0300 UTC.  A 15/0003 UTC QuikScat pass indicated
  a 25-30 kt LLCC.  The system was centered approximately 115 nm north-
  east of Madras at the time.  In the meantime, IMD had classified the
  LOW as a depression by early on the 15th.

     By 0900 UTC IMD had upgraded the depression to a deep depression
  (MSW of 30 kts), and at 1200 UTC it was further upgraded to a cyclonic
  storm (MSW of 35 kts).  The storm was then located about 75 nm east-
  northeast of Madras or 90 nm east-southeast of Nellore.  In the SWTO
  issued at 1800 UTC, JTWC mentioned that a 15/1232 UTC QuikScat pass
  had revealed a LLCC with 25-30 kt winds, therefore, JTWC did not
  initiate warnings on the system.  A second TCFA was issued at 16/0300
  UTC, noting that the center was exposed with the convection sheared to
  the west.  However, a bulletin issued by IMD at the same time indicated
  that the center of the cyclonic storm had crossed the south Andhra
  Pradesh coast earlier in the morning near Nellore.  With the center
  inland, JTWC cancelled the TCFA at 1600 UTC.    Bulletins from IMD
  indicated that the system had weakened into a depression by 16/2100
  UTC and was centered about 100 km northwest of Nellore.  By 0300 UTC
  on the 17th the system had moved northwestward and weakened further
  over central Andhra Pradesh.


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

  Activity for October:  1 tropical depression ++
                         1 severe tropical storm **

  ++ - Classified as a minimal tropical storm by JTWC
  ** - System originated 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 October

     Not long after the sun had crossed the equator on its annual south-
  ward journey, the first stirrings in the South Indian Ocean began
  to be seen.   A disturbance during the first week of October a few
  hundred miles east of Diego Garcia became both JTWC's and RSMC La
  Reunion's first numbered tropical system of the 2001-2002 Southern
  Hemisphere season.  The system remained weak, but since JTWC briefly
  upgraded the winds to 35 kts, and since MFR archives 30-kt tropical
  depressions in their Best Track database, I am including a short
  summary of this depression below.   Late in the month the Southwest
  Indian basin saw more tropical cyclone activity in the form of a
  visitor from the Australian Region.  Tropical Cyclone Alex was named
  by the Perth TCWC on 26 October and subsequently moved westward,
  crossing longitude 90E the next day and receiving the name Andre from
  the Mauritius Meteorological Service.   Since Alex-Andre originated
  in the Perth TCWC, it will be covered in the Northwest Australia/
  Southeast Indian Ocean section of this summary.

                  Tropical Depression  (TC-01S / MFR #01)
                               4 - 8 October

     A STWO issued by JTWC at 0400 UTC on 2 October mentioned that an
  area of convection had formed several hundred miles east of Diego
  Garcia.  Satellite imagery revealed disorganized convection in the
  area and a QuikScat pass indicated the existence of a weak LLCC.
  By the 3rd the system had moved to the southwest from its position
  the previous day and seemed a bit better organized, so JTWC upgraded
  the development potential to fair.  Some deep convection was noted,
  and a 200-mb analysis indicated that the disturbance lay beneath an
  upper-level ridge axis under diffluent flow.  Satellite imagery on
  4 October revealed an exposed LLCC to the northeast of deep convection.
  The LOW was located roughly 600 nm east-southeast of Diego Garcia, and
  lay on the equatorward side of an upper-level ridge axis with moderate
  northeasterlies aloft.  The maximum winds were estimated to be 20 to
  25 kts.

     The system remained quasi-stationary on the 5th with little change
  in appearance.  MFR initiated warnings on the developing system at
  05/0600 UTC with the center located roughly 650 nm east-southeast of
  Diego Garcia.  By late in the day animated satellite imagery depicted
  an increase in deep convection over a partially-exposed LLCC, so JTWC
  issued a TCFA at 2300 UTC.    In the meantime MFR had upgraded the 
  disturbance to tropical depression status with 30-kt winds (10-min 
  mean) at 1800 UTC.  The depression was still experiencing some vertical
  shear, but had good outflow aloft.   JTWC issued their first warning on
  TC-01S at 06/0600 UTC, placing the center about 665 nm east-southeast 
  of Diego Garcia and moving southward at 7 kts.   The initial warning 
  intensity was estimated at 35-kts (1-min avg), which was very much in 
  line with MFR's estimated 10-min avg wind of 30 kts.  Satellite imagery
  revealed an exposed LLCC approximately 30 nm east of the deep 
  convection.  A 200-mb analysis indicated that the system lay under 20 
  to 30 kts of vertical shear.

     MFR's intensity estimate remained at 30 kts, and on the second JTWC
  warning at 06/1800 UTC, the MSW was lowered to 30 kts.  The center
  remained exposed and convection was weakening.  Over the next couple
  of days the system moved slowly southward and southwestward.  The
  center remained partially-exposed with cycling convection which
  gradually weakened.  MFR downgraded the depression to a tropical
  disturbance at 0600 UTC on the 7th and issued their final bulletin at
  07/1800 UTC.    The final JTWC warning at 08/0600 UTC noted that
  animated satellite imagery revealed very weak cycling convection with
  no evidence of a LLCC.  The dissipating system's final position was
  approximately 720 nm southeast of Diego Garcia.   No casualties or
  damage are known to have resulted from this tropical depression.



  Activity for October:  1 tropical cyclone of storm intensity **

  ** - System moved west of 90E into Southwest Indian Ocean basin

     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.
  Information gleaned from JTWC's warnings was used as a supplement for 
  times when it was impossible to obtain Australian bulletins and for 
  comparison purposes.  References to sustained winds should be under-
  stood as being based on a 10-min averaging period unless otherwise 

                Northwest Australia/Southeast Indian Ocean
                      Tropical Activity for October

     The first tropical cyclone of the 2001-2002 season in the Australian
  Region formed during the last week of October a few hundred miles
  northwest of Cocos Island.  Named Alex by the Perth TCWC, the cyclone
  moved westward across longitude 90E into the Southwest Indian Ocean
  basin where it was renamed Andre by Mauritius.   A little explanation
  might be useful here regarding the use of the term "severe".  Alex was
  referred to as "Tropical Cyclone Alex" east of 90E, but became "Severe
  Tropical Storm Andre" upon entering the Southwest Indian basin,
  although the reported intensity remained about the same.  In the
  Australian Region, a "severe tropical cyclone" is one in which maximum
  10-min mean winds exceed 64 kts, i.e., a cyclone of hurricane
  intensity.  But west of 90E a "severe tropical storm" is a system with
  10-min average winds in the range of 48-63 kts.  More information on
  the particular terminology used by the various TCWCs can be found in
  the summary for April, 2001 (Feature of the Month section).

              Tropical Cyclone Alex-Andre  (MFR #2 / TC-02S)
                              24 - 31 October

  A. Storm Origins

     At 1000 UTC on 24 October JTWC issued a STWO which mentioned that an
  area of convection that had developed earlier was located in the South
  Indian Ocean southwest of Sumatra or a few hundred miles north of Cocos
  Island.    Persistent deep convection was associated with a broad, 
  poorly-organized LLCC.  A 200-mb analysis indicated that the region was
  beneath weak northerly winds associated with an extension of an upper-
  level ridge.   At 1000 UTC on the 25th JTWC relocated the disturbance
  farther to the west and upgraded the development potential to fair.
  Animated infrared and visible satellite imagery revealed a well-defined
  LLCC with increasing organization of deep convection.  A SSM/I pass had
  indicated that the primary convection was situated along the southern
  periphery of the LLCC.

     JTWC issued a TCFA at 25/1600 UTC, upgrading the potential for
  development to good.  Maximum winds were estimated at 20 to 30 kts.
  At 0300 UTC on 26 October the Perth TCWC issued a gale warning for
  the LOW in anticipation of further development.  At 0600 UTC the system
  was upgraded to Tropical Cyclone Alex, located about 300 nm northwest
  of Cocos Island.  Also at 0600 UTC, JTWC issued their first warning
  on the system, estimating the MSW to be 35 kts.    Perth's warning 
  estimated the peak winds to be 30-45 kts (10-min avg).  Alex displayed
  a well-developed LLCC with deep convection wrapping into the center of
  the cloud system.  The cyclone was situated in a weakness between a
  mid-level HIGH to the northwest and a stronger ridge to the east-

  B. Track and Intensity History

     After being upgraded to tropical cyclone status, Alex moved slowly
  westward.  Upper-level northeasterlies continued to shear the system,
  hampering the intensification process.  By 1800 UTC on 27 October deep
  convection had become better organized with both JTWC and Perth
  estimating the intensity at 50 kts.  Alex continued to be steered west-
  ward to west-southwestward by a mid-level ridge situated to the south-
  east.    At 27/1800 UTC the cyclone was located about 525 nm north-
  west of Cocos Island and just east of the 90th meridian.  By 0000 UTC
  on the 28th Alex had entered the Southwest Indian Ocean basin and had
  been renamed Andre by Mauritius.   Alex-Andre was near its peak
  intensity at this time with the MSW as reported by both JTWC and MFR
  being 55 kts (1-min and 10-min averages, respectively).  A 10-min avg
  wind of 55 kts would equate to a 1-min avg of 65 kts, and the JTWC
  warnings on 28 October noted that there were some CI estimates of
  65 kts received.   Severe Tropical Storm Andre (by MFR's terminology)
  tracked slowly to the southwest on the 28th with some evidence of
  shearing evident by 1800 UTC, the system being located in a region of 
  moderate northeastly shear equatorward of the subtropical ridge.

     Andre's track became west-southwesterly and later westerly on
  29 October.  Convection seemed to increase early in the day, but by
  1800 UTC the deep convection had been sheared to the west of the LLCC
  and had decreased in coverage.  MFR and JTWC lowered the MSW estimates
  to 35 and 45 kts, respectively, at 1800 UTC.   JTWC's 29/0600 UTC
  warning had forecast slow intensification, but the 1800 UTC warning
  called for no strengthening with weakening after 36 hours.   The shear
  continued unabated on 30 October and Andre continued to slowly weaken.
  By 1800 UCT, MFR and JTWC had lowered their respective MSW estimates
  to 30 and 35 kts.  The storm at this time was located roughly 600 nm
  east-northeast of Diego Garcia.

     Andre's center was apparently quite difficult to pinpoint on 30 and
  31 October as there were quite a bit of discrepancies between MFR's and
  JTWC's coordinates.  The best estimate is that the storm halted its
  westward motion and jogged back to the east-northeast late on the 30th
  before embarking on a southwesterly track once more early on the 31st.
  The JTWC warning issued at 31/0000 UTC notes that the LLCC was embedded
  in a larger, broad circulation and was difficult to locate.  By 1800
  UTC on 31 October, Andre's LLCC had broadened and become disorganized.
  Therefore, both MFR and JTWC issued their final warnings on the system
  at that hour, placing the dissipating center approximately 400 nm
  east-southeast of Diego Garcia.  A weak remnant LOW remained in the
  area for a couple of days but showed no signs or regeneration.

  C. Comparisons between Perth/MFR and JTWC

     Intensity estimates basically were in good agreement between the
  official Southern Hemisphere warning centres and JTWC.  Over the past
  few years that I have been writing these summaries, I have noticed a
  persistent upward bias in Perth's reported 10-min avg MSW estimates
  as compared with JTWC's, and this was the case for Tropical Cyclone
  Alex.  However, for the time of peak intensity when the cyclone crossed
  90E, the values from Perth and La Reunion were in excellent agreement.
  JTWC's equivalent 1-min avg MSW was close, but represented a slightly
  weaker storm than that estimated by the Southern Hemisphere centres.
  But, as noted above, JTWC did receive some CI estimates of 65 kts but
  chose to be slightly on the conservative end.  During Andre's weakening
  phase, the intensities reported by JTWC and MFR were in close agree-

  D. Damage and Casualties

     No reports of damage or casualties resulting from Tropical Cyclone
  Alex-Andre have been received.



  Activity for October:  1 tropical LOW

                       Northeast Australia/Coral Sea
                       Tropical Activity for October

     There were no tropical cyclones or well-organized tropical LOWS in
  the Gulf of Carpentaria or Coral Sea during October, but there was
  one system which deserves a brief mention.  The equatorial westerly
  wind burst around mid-month which produced Super Typhoon Podul in the
  North Pacific helped to spawn a weak "twin" south of the equator.  This
  system did not show any significant signs of development until the 25th
  when a fairly well-defined LOW center formed near Bougainville.  The
  TCWC at Port Moresby, Papua New Guinea, issued a gale wind warning for
  the 1005-mb LOW, which at 25/1030 UTC was located approximately 60 nm
  southwest of Bougainville Island or about 145 nm northeast of Woodlark
  Island.  Gale-force winds and severe squalls of 34-45 kts were forecast
  to occur and persist for the next 6 to 12 hours.  The deep convection
  associated with this LOW developed against the diurnal trend as an
  upper-level trough was crossing Australia.    However, the upper-level
  trough also eventually brought detrimental vertical wind shear over the
  system and it soon weakened.  (A special thanks to Jeff Callaghan of
  the Brisbane TCWC for forwarding me a copy of the Port Moresby warning
  and for providing some information on this system.)


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

  Activity for October:  No tropical cyclones

                              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
           October as an example:   oct01.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:  oct01.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 2000 and a report on the 2000-2001 season in
  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:>

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


Document: summ0110.htm
Updated: 27th December 2006

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