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Monthly Global Tropical Cyclone Summary December 2004
[Summaries and Track Data] [Prepared by Gary Padgett]


                              DECEMBER, 2004

  (For general comments about the nature of these summaries, as well as
  information on how to download the tabular cyclone track files, see
  the Author's Note at the end of this summary.)


                           DECEMBER HIGHLIGHTS

   --> Two tropical storms stir Western Pacific waters
   --> Tropical cyclone moves southward through central Indian Ocean
   --> South Pacific tropical cyclone forms east of Tahiti


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

                        FOR THE NORTHERN HEMISPHERE

     Following is a tabular summary of all the tropical depressions,
  tropical storms, hurricanes, and typhoons which occurred in the
  Northern Hemisphere between 1 January and 31 December 2004, as
  reported in the Monthly Global Tropical Cyclone Summaries prepared
  by the author.

    (1) Number - this is the sequential cyclone number assigned by either
                 TPC/NHC, CPHC in Honolulu, or JTWC.  If neither of these
                 agencies issued any warnings, no number will be given.

    (2) Name - the name (if any) assigned by either TPC/NHC, CPHC, or
               JMA (and PAGASA for Western North Pacific systems in 
               their area of warning responsibility).

    (3) Dates - range of dates for which tracking information for the 
                cyclone is available in the Global Tropical Cyclone
                Tracks files prepared by the author.

    (4) Pressure - Lowest central pressure (either estimated or recorded)
                   during the lifetime of the cyclone.  For Atlantic and
                   Northeastern Pacific systems these will be the values
                   reported in operational advisories from TPC/NHC or
                   CPHC.  For Northwest Pacific systems the central
                   pressure estimates are taken from advisories issued by
                   the Japanese Meteorological Agency.  An asterisk (*)
                   following the pressure indicates the reading was an
                   actual measured pressure normally obtained by a drop-
                   sonde released during an aerial reconnaissance
                   flight.    Central pressure is given in millibars,
                   which is numerically equivalent to hectopascals.

    (5) MSW - maximum 1-minute average sustained windspeed in knots.
              For the Northwestern Pacific and North Indian Ocean
              basins, these will be the highest value assigned
              operationally by JTWC.  For the Atlantic and Northeastern
              Pacific basins, the MSW values are taken from the
              official tropical cyclone reports prepared by the
              TPC/NHC Hurricane Specialists and which are available
              on TPC/NHC's website:> .

    (6) Basins - tropical cyclone basins where the cyclone tracked during
                 its life:

                 ATL - North Atlantic, Gulf of Mexico, Caribbean Sea
                 NEP - North Pacific east of Longitude 180
                 NWP - North Pacific west of Longitude 180
                       (including South China Sea)
                 NIO - Bay of Bengal and Arabian Sea

     For tropical systems in the NWP basin, two additional columns of
  information are given:

     (1) The tropical storm serial number assigned by the Japanese
         Meteorological Agency to tropical depressions which are deemed
         to have reached tropical storm intensity.  This does not always
         agree with JTWC's assessment.

     (2) An estimate of the maximum 10-minute average sustained wind.
         The value given represents the highest 10-min avg MSW assigned
         by any agency.  If from any warning center other than JMA, a
         numbered note below identifies which center's value is given.

     For tropical systems in the NIO basin, a column is given referencing
  IMD's identifier for cyclonic storms:  ARB for Arabian Sea cyclones and
  BOB for Bay of Bengal systems.

     A number in parentheses (e.g. (1) ) following an entry refers to
  a note following the entries for the given basin.   A separate table
  is given for each of the four Northern Hemisphere basins.


                             ATLANTIC BASIN

 NUM  NAME          DATES           CENT PRS   MSW               BASIN
                                      (mb)    (kts)

 01   Alex          31 Jul-06 Aug      957 *   105                ATL
 02   Bonnie        03-14 Aug         1001 *    55                ATL
 03   Charley       09-15 Aug          941 *   130                ATL
 04   Danielle      13-24 Aug          964      95                ATL
 05   Earl          13-15 Aug         1009 *    45                ATL
 06   Frances       25 Aug-10 Sep      935 *   125                ATL
 07   Gaston        27 Aug-03 Sep      985 *    65                ATL
 08   Hermine       27-31 Aug         1002 *    50                ATL
 09   Ivan          02-24 Sep          910 *   145                ATL
 10   -----         07-10 Sep         1009      30                ATL
 11   Jeanne        13-29 Sep          950 *   105                ATL
 12   Karl          16-28 Sep          938     125                ATL
 13   Lisa          19 Sep-03 Oct      987      65                ATL
 14   Matthew       08-11 Oct          997 *    40                ATL
 15   Nicole        10-11 Oct          986      45                ATL (1)
 16   Otto          26 Nov-05 Dec      995      45                ATL (2)


 (1) System was a subtropical storm which never developed full tropical
     cyclone characteristics.

 (2) System was initially a subtropical storm which evolved into a tropical
     storm.  The peak winds of 45 kts occurred during the subtropical storm
     stage--the highest MSW after transforming into a tropical storm was
     40 kts.


                         NORTHEAST PACFICIC BASIN

 NUM  NAME          DATES           CENT PRS   MSW               BASIN
                                      (mb)    (kts)

 01E  Agatha        22-26 May          997      50                NEP
 02E  -----         02-05 Jul         1007      30                NEP
 01C  -----         05 Jul            1007      25                NEP
 03E  Blas          12-19 Jul          991      55                NEP
 04E  Celia         19-26 Jul          981      75                NEP
 05E  Darby         26 Jul-01 Aug      957     105                NEP
 06E  -----         29 Jul-03 Aug     1006      30                NEP
 07E  Estelle       19-25 Aug          989      60                NEP
 08E  Frank         23-27 Aug          979      75                NEP
 09E  -----         23-28 Aug         1005      30                NEP
 10E  Georgette     26 Aug-03 Sep      995      55                NEP
 11E  Howard        30 Aug-10 Sep      943     120                NEP
 12E  Isis          08-21 Sep          987      65                NEP
 13E  Javier        10-20 Sep          930     130                NEP
 14E  Kay           04-07 Oct         1004      40                NEP
 15E  Lester        11-13 Oct         1000      45                NEP
 16E  -----         25-26 Oct         1004      30                NEP


                         NORTHWEST PACFICIC BASIN

 JTWC    NAME(S)      JMA     DATES         CENT    MSW   MSW    BASIN
 NUM                TROP STM                PRS    1-MIN 10-MIN
                      NUM                   (mb)   (kts) (kts)

 01W  Ambo            ----  11-16 Feb       1000     45    30     NWP (1)
 02W  Butchoy         ----  16-23 Mar        998     45    45     NWP (2)
 03W  Sudal/Cosme     0401  03-18 Apr        940    130    95     NWP (3)
 04W  Nida/Dindo      0402  13-22 May        930    140   110     NWP (4)
 05W  -----           ----  14-20 May       1002     35    30     NWP (1)
 06W  Omais/Enteng    0403  16-23 May        985     65    50     NWP
 07W  Conson/Frank    0404  04-11 Jun        960     95    80     NWP (5)
 08W  Chanthu/Gener   0405  07-15 Jun        970     75    65     NWP
 09W  Dianmu/Helen    0406  12-23 Jun        915    155   130     NWP (5)
 10W  Mindulle/Igme   0407  23 Jun-05 Jul    940    125   105     NWP (2)
 11W  Tingting        0408  25 Jun-06 Jul    945     80    85     NWP
 12W  Kompasu/Julian  0409  13-16 Jul        990     45    45     NWP
 13W  Namtheun        0410  24 Jul-01 Aug    945    115   100     NWP (5)
 ---  NMCC TS-0411    ----  26-27 Jul        990     --    45     NWP (6)
 14W  Meranti         0412  03-09 Aug        960     90    75     NWP
 15W  Malou           0411  04-06 Aug        994     30    40     NWP
 ---  -----           ----  06-07 Aug       1002     --    30     NWP (7)
 16W  Rananim/Karen   0413  06-13 Aug        950     90    90     NWP (5)
 17W  Malakas         0414  10-13 Aug        990     35    45     NWP
 18W  Megi/Lawin      0415  14-22 Aug        970     65    65     NWP
 19W  Chaba           0416  18 Aug-03 Sep    910    155   130     NWP (5)
 20W  Aere/Marce      0417  19-31 Aug        955     85    80     NWP
 21W  -----           ----  26-31 Aug       1000     35    30     NWP (1)
 22W  Songda/Nina     0418  27 Aug-11 Sep    925 *  130   120     NWP (5)
 23W  Sarika          0419  03-09 Sep        980     60    60     NWP (5)
 ---  NMCC TD04       ----  08-11 Sep       1002     --    30     NWP
 24W  Haima/Ofel      0420  10-14 Sep        996     30    40     NWP
 ---  Pablo           ----  14-18 Sep       1006     --    30     NWP
 ---  NMCC TD06       ----  15-16 Sep       1006     --    30     NWP
 25W  Meari/Quinta    0421  20 Sep-01 Oct    940    120   100     NWP (5)
 26W  Ma-on/Rolly     0422  03-10 Oct        920    140   105     NWP (8)
 27W  Tokage/Siony    0423  12-23 Oct        940    125   100     NWP (5)
 28W  Nock-ten/Tonyo  0424  14-27 Oct        945    110    90     NWP (5)
 29W  Muifa/Unding    0425  14-26 Nov        955    115    90     NWP (5)
 ---  Merbok/Violeta  0426  22-23 Nov        998     --    35     NWP 
 ---  Winnie          ----  27-30 Nov       1000     --    30     NWP
 30W  Nanmadol/Yoyong 0427  28 Nov-04 Dec    935    130   100     NWP (2)
 31W  Talas/Zosimo    0428  10-21 Dec        992     45    40     NWP
 32W  Noru            0429  17-23 Dec        990     55    50     NWP (5)


 (1) Classified as a tropical storm by JTWC only.

 (2) The highest 10-min avg MSW was assigned by PAGASA. 

 (3) The highest 10-min avg MSW was assigned by HKO.

 (4) The highest 10-min avg MSW was assigned by HKO and NMCC.

 (5) The highest 10-min avg MSW was assigned by NMCC.

 (6) NMCC was the only agency to classify this system as a tropical

 (7) Classified as a tropical depression by JMA only.

 (8) The highest 10-min avg MSW was assigned by the CWB of Taiwan.


                       NORTH INDIAN OCEAN BASIN

 NUM  NAME        IMD ID       DATES        CENT PRS   MSW       BASIN
                                              (mb)    (kts)

 01A  -----      ARB0401     05-10 May         ---      45        NIO
 02B  -----      BOB0401     17-19 May         ---      60        NIO
 03A  Onil       ARB0402     01-09 Oct         ---      40        NIO (1)
 ---  -----      -------     02-08 Oct         ---      25        NIO (2)
 04A  -----      -------     04-07 Nov         ---      40        NIO
 05A  Agni       ARB0403     28 Nov-03 Dec     ---      65        NIO


 (1) Onil was quite likely more intense than indicated in the warnings
     from JTWC.  SAB ranked the cyclone at T3.5/3.5 (55 kts) on 1 and
     2 October.

 (2) This system was treated as a depression by IMD.  No track was
     available for inclusion in the Global Tropical Cyclone Tracks
     File for October; however, a short report can be found in the
     October monthly summary.

                            ACTIVITY BY BASINS

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

  Activity for December: No tropical cyclones

                  Atlantic Tropical Activity for December

     As the month of December opened, the final tropical cyclone of the
  2004 season, Tropical Storm Otto, was meandering around in the central
  North Atlantic.  Otto weakened on the 2nd, was downgraded to a tropical
  depression and the final advisory written.  However, a remnant LOW
  persisted for several more days.  The report on Tropical Storm Otto can
  be found in the November summary.


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

  Activity for December:  No tropical cyclones


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

  Activity for December:  2 tropical storms

                         Sources of Information

     Most of the information presented below is based upon tropical
  cyclone warnings and significant tropical weather outlooks issued
  by the Joint Typhoon Warning Center of the U. S. Air Force and
  Navy (JTWC), located at Pearl Harbor, Hawaii.   In the companion
  tropical cyclone tracks file, I normally annotate track coordinates
  from some of the various Asian warning centers when their center
  positions differ from JTWC's by usually 40-50 nm or more.   All
  references to sustained winds imply a 1-minute averaging period
  unless otherwise noted.

     Michael V. Padua of Naga City in the Philippines, owner of the
  Typhoon 2000 website, normally sends me cyclone tracks based upon
  warnings issued by the Japanese Meteorological Agency (JMA) and the
  Philippine Atmospheric, Geophysical & Astronomical Services
  Administration (PAGASA).  Also, Huang Chunliang of Fuzhou City, China,
  sends data taken from synoptic observations around the Northwest
  Pacific basin.  A very special thanks to Michael and Chunliang for
  the assistance they so reliably provide.

     In the title line for each storm I have referenced 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 warning responsibility.

              Northwest Pacific Tropical Activity for December

     The active 2004 Northwest Pacific season finally ended in late
  December just as the year was about to end.  As the month of December
  opened, intense Typhoon Nanmadol/Yoyong was about the strike the island
  of Luzon--the fourth tropical system to plague that area in only three
  weeks.  After crossing Luzon Nanmadol recurved sharply in the north-
  eastern South China Sea as it weakened.  The system subsequently crossed
  over the southern portion of Taiwan as it transformed into an extra-
  tropical cyclone.  The full report on Nanmadol can be found in the
  November summary.

     Two other tropical cyclones formed during December with neither
  reaching typhoon status.  Tropical Storm Talas (named Zosimo by PAGASA)
  followed a long trajectory from the Marshall Island area westward,
  passing well south of the Marianas, and eventually recurving east of
  the Philippines.  Talas was in warning status from the 10th until the
  19th--a fairly long life span for a relatively weak system.   Shortly
  after mid-month Tropical Storm Noru sprang up in the Caroline Islands and
  moved northward, recurving just east of the Mariana Islands.  Although
  much shorter-lived than Talas, Noru was the stronger of the two, reaching
  severe tropical storm status per JMA's nomenclature.  Reports on these
  two tropical storms, authored by Kevin Boyle, follow.

                          TROPICAL STORM TALAS
                      (TC-31W / TS 0428 / ZOSIMO)
                            10 - 21 December
  Talas: contributed by the Philippines, means 'acuteness' or

  A. Storm Origins

     At 0130 UTC 9 December a new area of convection developed and
  persisted approximately 630 nm east-southeast of Kwajalein, a position
  located deep within the Western North Pacific close to the border with
  the Central North Pacific.  At this time, multi-spectral satellite
  imagery showed organized deep convection beginning to consolidate over
  a possible LLCC.  An upper-level analysis revealed that the suspect area
  was within a moderate wind shear environment coupled with some
  diffluence.  Based on this, the development potential for the formation
  of a significant tropical cyclone was assessed as 'poor'.  This was soon
  raised to 'fair' at 09/0600 UTC, and as the overall organization of the
  system continued to improve, was followed by a TCFA at 09/2200 UTC.  The
  first warning was issued at 10/0000 UTC, the west-northwest to northwest
  heading bringing the newly-formed Tropical Depression 31W to within
  220 nm east-southeast of Kwajalein.

  B. Synoptic History

     Tropical Depression 31W was an immediate threat to Kwajalein,
  Ailinglaplap and Ujae, and a tropical storm warning was issued for those
  islands as soon as the first warning was issued by JTWC.    Despite
  exhibiting a partially-exposed LLCC, TD-31W was upgraded to a 35-kt
  tropical storm at 1200 UTC 10 December while it was passing Kwajalein 
  Atoll with sustained winds reaching tropical storm force.  Moving west-
  ward Tropical Storm 31W's intensity strengthened to 45 kts at 11/0000
  UTC and this strength was to be maintained for the next couple of days.
  In fact, this was to be the peak MSW estimated for this system.  The
  storm was named Talas at 11/0600 UTC when JMA upgraded it to a 35-kt
  tropical storm.  Tracking westward, Talas passed well to the north of
  Kosrae at 11/0300 UTC, its forward speed increasing to around 23 kts.  
  Although the LLCC was located beneath an almost symmetrical CDO, it
  became fully-exposed at 12/0000 UTC with a marked decrease in deep
  convection, which was confined mainly to the western periphery.

     At 0000 UTC 12 December Tropical Storm Talas was far to the east-
  southeast of Guam, being located approximately 665 nm from the island.
  Its westerly heading, governed by the subtropical ridge to the north,
  took it a little over 200 nm north of Chuuk at 12/0900 UTC.  After what
  seemed to be a reorganizing phase, the system's centre became partially-
  exposed again.  However, the warning at 13/0000 UTC indicated that the
  deep convection was becoming better-organized.  Nonetheless, Talas lacked
  a significant outflow pattern.   In any case, weakening began at 13/1200
  UTC, shortly after Talas had tracked nearly 200 nm to the south of Guam
  and also well south of Saipan, Tinian, and Rota.    The MSW dropped to
  35 kts at 13/1800 UTC but picked up a little to 40 kts six hours later.
  This intensity was maintained through the 14th, a day of little to write
  about.  Talas passed safely north of Yap between 14/1200 UTC and 14/1800

     At 0000 UTC 15 December Talas slowed somewhat as it continued westward
  along the southwestern portion of the steering ridge--the storm was
  located approximately 190 nm northwest of Yap at this time.   The
  intensity had fallen to 35 kts and this was maintained for another six
  hours before Talas was downgraded to a 30-kt tropical depression at
  15/1200 UTC.  At this time, the weak tropical system had drifted into 
  PAGASA's AOR and was named Zosimo by that agency.  The MSW remained at
  30 kts through the 16th as the rather disorganized storm's westward
  motion persisted, but this changed at 16/1200 UTC as a northwesterly
  motion commenced.    The forward speed slowed further as the steering
  currents slackened and by 17/0000 UTC Talas was crawling along at 3 kts.

     At 0000 UTC 17 December Tropical Depression Talas was located
  approximately 615 nm east of Manila, Philippines.  Initially moving 
  slowly northwestward, the system turned north as it began to nudge into
  a weakness in the subtropical ridge.  At this time, deep convection began
  to rapidly flare up, resulting in an expanding CDO.  The MSW rose to
  35 kts at this time and Talas was reinstated as a tropical storm.  It
  soon re-intensified back to its earlier peak intensity of 45 kts at
  17/0600 UTC.  Continuing slowly northward, Talas' strength started to
  wane again and fell to 40 kts at 17/1800 UTC.  At 18/0000 UTC Tropical
  Storm Talas was nearly stationary 820 nm southwest of Iwo Jima and
  weakened a little more to 35 kts at 18/0600 UTC, but held on to minimal
  tropical storm strength for the rest of the 18th as it began to speed up
  a little towards the north.  The cyclone began to fall apart early on
  the 19th as the LLCC split from the deep convection.    Talas was down-
  graded to a tropical depression at 19/0600 UTC, and JTWC logged the
  system for the final time at 19/1200 UTC after 39 warnings--the final 
  position 700 nm west-southwest of Iwo Jima.   JMA continued to follow
  the remnant weak depression eastward along the 20th parallel for a couple
  more days.

     Tropical Storm Talas was an average-sized system with gales extending
  no further than 110 nm from the centre in any one quadrant.

     The peak MSW estimated by JMA, NMCC and CWB was 40-kts (10-min avg)
  with the lowest estimated CP per JMA warning being 992 mb.   During the
  period that Talas/Zosimo was within PAGASA's AOR the maximum intensity 
  reckoned by that agency was 35 kts.  HKO issued no warnings on this

     A graphic displaying the track of Tropical Storm Talas/Zosimo may be
  found at the following link:>

  C. Damage and Casualties

     There were no damages or casualties reported in association with 
  Tropical Storm Talas.

  (Report written by Kevin Boyle)

                          TROPICAL STORM NORU
                           (TC-32W / TS 0429)
                            17 - 23 December

  Noru: contributed by the Republic of Korea, is the roe deer--a type
        of small deer which lives in the forest

  A. Storm Origins

     Tropical Storm Noru stemmed from an area of convection that had
  persisted approximately 235 nm northeast of Chuuk.  JTWC issued a TCFA
  on this suspect area at 0300 UTC 17 December, a QuikScat pass at 16/1950
  UTC revealing a broad, well-defined LLCC.   Water vapor imagery showed
  deep convection starting to consolidate around this centre with strong
  radial outflow associated with the system.  Since an upper-level analysis
  indicated an environment of low vertical shear and favourable divergence,
  further development was expected.     The first warning on Tropical
  Depression 32W was released at 17/1800 UTC with the system moving west-
  northwest at 7 kts, located at that time 370 nm east-southeast of Saipan.
  It was upgraded to a tropical storm at 18/0600 UTC when satellite CI 
  estimates had reached 35 kts, and because of the threat posed by this 
  tropical cyclone to the Marianas, the National Weather Service on Guam 
  urged the island communities to monitor the progress of this storm.      
  The intensity remained at 35 kts throughout the 18th as the storm 
  continued westward, and the system was named Noru when JMA upped their 
  MSW to 35 kts at 1800 UTC on 18 December.

  B. Synoptic History

     At 0000 UTC 19 December Tropical Storm Noru was maintaining 35-kt
  winds approximately 165 nm southeast of Saipan.      At this time, it
  decelerated and veered sharply north-northwestwards, passing 50 nm east
  of Saipan at 19/1200 UTC.    Three hours later, Noru made its closest
  approach to Tinian, roughly 85 nm to the east-northeast.  During this
  period it had undergone a strengthening phase which brought the MSW up
  to 50 kts at 19/1800 UTC.  Tropical Storm Noru reached its peak intensity
  of 55 kts at 20/0000 UTC when it began pushing northwards, and at 20/0300
  UTC Noru was passing roughly 45 nm east of Pagan and around 45 nm east
  of Agrihan three hours later.

     Noru completed recurvature at 20/1800 UTC and began to track towards
  the northeast, its associated cloud pattern becoming elongated with cold,
  dry air entraining from the west, a sign that extratropical transition
  was underway.  The MSW had remained 55 kts up to this point but began to
  slowly fall off at 21/0000 UTC.    The tropical cyclone continued north-
  eastward and had merged with a baroclinic zone by 21/0600 UTC.  JTWC
  issued the final warning at this time, placing the 45-kt extratropical
  system some 815 nm west-northwest of Wake Island.  JMA maintained Noru as
  a 45-kt tropical storm through the 22nd and gradually weakened the storm
  down to 35 kts by 23/1200 UTC.    The intensity was brought back up to
  40 kts when JMA mentioned ex-Noru for the last time in their bulletins
  at 23/1800 UTC.   The extratropical gale by this time had crossed the 
  Dateline into the Central North Pacific and was still racing rapidly 

     Tropical Storm Noru was somewhat smaller than average with the radius
  of storm-force winds never exceeding 20 nm while gales extended no
  further than 80 nm in any one quadrant.

     NMCC considered Noru as a 50-kt severe tropical storm while JMA
  estimated a peak intensity of 45-kts and a minimum CP of 990 mb.  CWB
  estimated a maximum intensity of 40-kts.

     A graphic displaying the track of Tropical Storm Noru may be found
  at the following link:>

  C. Damage and Casualties

     There were no reports of damages or casualties from any of the islands
  in association with Tropical Storm Noru.

  (Report written by Kevin Boyle)


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

  Activity for December:  No tropical cyclones

             North Indian Ocean Tropical Activity for December

     No tropical cyclones or depressions formed in the North Indian Ocean
  basin during December.  As the month opened Severe Cyclonic Storm Agni
  was weakening as it moved westward through the southern Arabian Sea.
  Agni had been of hurricane intensity on 29 and 30 November but had
  weakened into a tropical storm late on the 30th.  Agni had the unusual
  distinction of having reached tropical storm intensity only 40 nm north
  of the equator!  The report on Agni can be found in the November summary.


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

  Activity for December:  1 subtropical depression
                          1 tropical cyclone

                        Sources of Information

     The primary sources of tracking and intensity information for
  Southwest Indian Ocean tropical cyclones are the warnings issued by
  the Tropical Cyclone Warning Centre on La Reunion Island, part of
  Meteo France (MFR), and the Regional Specialised Meteorological Centre
  for the basin.    However, tropical cyclones in this region are named 
  by the sub-regional warning centres on Mauritius and Madagascar with
  longitude 55E being the demarcation line between their respective
  areas of warning responsibility.  The La Reunion centre only advises
  these agencies regarding the intensity of tropical systems.  References
  to sustained winds imply a 10-minute averaging period unless otherwise

     In the companion tropical cyclone tracks file, I occasionally
  annotate positions from warnings issued by the Joint Typhoon Warning
  Center (JTWC) of the U. S. Air Force and Navy, located at Pearl
  Harbor, Hawaii, when they differ from MFR's coordinates by usually
  40-50 nm or more.  The JTWC warnings are also the source of the
  1-minute average maximum sustained wind values included in the
  tracks file.    Additionally, information describing details of
  satellite imagery and atmospheric circulation features included in
  the narratives is often gleaned from the JTWC warnings.

            Southwest Indian Ocean Tropical Activity for December

     One named tropical system formed in the South Indian Ocean west of
  longitude 90E during December, and it reached tropical cyclone intensity.
  (In that basin, the term 'tropical cyclone' is equivalent to 'hurricane'
  in the Atlantic and Northeast Pacific basins and to 'typhoon' in the
  Northwest Pacific basin.)  Tropical Cyclone Chambo formed in the eastern
  portion of the region and pursued a southwesterly trajectory across the
  central South Indian Ocean, passing far to the southeast of Diego Garcia
  and well east of Rogrigues Island.  A report on this cyclone follows.

     MFR issued bulletins for one other system, designated as Subtropical
  Depression 05.  This very short-lived system (only two bulletins were
  issued) formed and dissipated on 11 December in the southern Mozambique
  Channel 200-300 nm west of the southern tip of Madagascar.  Maximum
  winds in this short-lived disturbance were estimated at only 25 kts.
  As brief as it was, a track was included for Subtropical Depression 05
  in the companion cyclone tracks file.

                         TROPICAL CYCLONE CHAMBO
                             (MFR-06 / TC-06S)
                         23 December - 2 January

  Chambo: contributed by Malawi

  A. Storm Origins

     Around 1800 UTC on 18 December an area of convection had formed about
  550 nm west-northwest of Jakarta, Indonesia, and persisted for 24 hours.
  The disturbance was located within a region of low vertical shear and
  favorable divergence aloft, and microwave imagery revealed a weak LLCC.
  Over the next few days the system drifted westward with little change.
  By 0900 UTC on 22 December the disturbance had reached a point slightly
  more than 400 nm northwest of the Cocos Islands.  Deep convection was
  increasing around an elongated LLCC, and the upper-level environment was
  still conducive to strengthening.  MFR initiated bulletins on Tropical
  Disturbance 06 at 23/0000 UTC, placing a weak 25-kt center approximately
  650 nm northwest of the Cocos.   JTWC issued a TCFA at 23/0100 UTC as
  the LLCC had become well-organized with increasing consolidation of deep
  convection.  MFR upgraded the disturbance to a 30-kt tropical depression
  at 23/0600 UTC, and JTWC issued their first warning on TC-06S at 1800

  B. Synoptic History

     JTWC's initial warning intensity of 35 kts (1-min avg) was based on
  CI estimates of 30 and 35 kts.  The system was then moving southward at
  8 kts, but soon turned to a southwesterly track which it would follow for
  most of its life.  Intensification proceeded slowly, and it was not until
  24/0600 UTC that MFR upgraded the depression to tropical storm status
  with Mauritius supplying the name Chambo.  Tropical Storm Chambo at
  that time was located approximately 750 nm west of the Cocos Islands
  and moving southwestward with 40-kt winds.   After reaching tropical
  storm intensity, Chambo intensified rather steadily, reaching cyclone
  (i.e., hurricane) intensity 24 hours later.  At 0600 UTC on Christmas
  Day Tropical Cyclone Chambo was located about 650 nm east-southeast of
  Diego Garcia sporting a MSW of 70 kts.

     For most of its existence Tropical Cyclone Chambo followed a general
  southwesterly course across the central South Indian Ocean, guided by
  a persistent anticyclone anchored to its southeast.  The intensity
  levelled off at 80 kts after 25/1200 UTC where it remained pegged for
  almost two days.  The cyclone reached its peak intensity of 85 kts at
  27/0000 UTC when centered approximately 725 nm southeast of Diego
  Garcia.  The minimum CP estimated by MFR was 945 hPa, and gales reached
  outward 90 nm from the center in most quadrants.  JTWC's peak 1-min avg
  MSW of 95 kts is in good accord with MFR's peak 10-min avg MSW of 85 kts.
  Thus, Chambo fell just shy of the 90 kts (10-min avg) required for
  classification as an intense tropical cyclone.

     The cyclone's motion had slowed somewhat as it reached its peak
  intensity and became mostly westerly for a day or so.    On the 27th a 
  west-southwesterly motion ensued, becoming southwesterly on the 28th.
  Chambo's decline following its peak was rather rapid.  Twenty-four hours
  after peaking at 85 kts, MFR's MSW had dropped to 50 kts, and JTWC's
  estimated 1-min avg MSW fell from 95 kts to 35 kts in a like time span.
  As Chambo moved poleward of the 18th parallel, it began to run into some
  rather strong vertical shear.   MFR lowered the cyclone to tropical storm
  status at 28/0000 UTC, placing the center about 725 nm south-southeast of
  Diego Garcia.  JTWC issued their final warning at 28/0600 UTC, basing the
  MSW of 35 kts (1-min avg) on final T-shear estimates ranging from 30 to
  45 kts and QuikScat data showing 35-40 kt winds associated with the
  LLCC.  The CI estimates were not followed since they remained at 45 and
  55 kts per Dvorak constraint rules.  Chambo's center was fully-exposed
  over 85 nm northeast of the remaining deep convection.
     MFR continued to classify Chambo as a slowly weakening tropical storm
  for another couple of days.  The system gradually transformed into an
  extratropical system, and was formally classified thusly by MFR at 0600
  UTC on 30 December when located about 500 nm southeast of Rodrigues
  Island.  The ex-Chambo system continued to move slowly southwestward,
  turning to the south early on 1 January.  Gales to 45 kts occurred during
  this period, and MFR continued issuing gale warning through 0000 UTC on
  2 January.    The final bulletin placed the 40-kt extratropical LOW
  approximately 675 nm south-southeast of Rodrigues Island.

     A graphic displaying the track of Tropical Cyclone Chambo may be
  found at the following link:>

  C. Damage and Casualties

     No damage or casualties are known to have resulted from Tropical
  Cyclone Chambo.

  (Report written by Gary Padgett)



  Activity for December:  1 tropical LOW **

  ** - classfied as a minimal tropical storm by JTWC

                        Sources of Information

     The primary sources of tracking and intensity information for
  Northwest Australia/Southeast Indian Ocean tropical cyclones are 
  the warnings and advices issued by the Tropical Cyclone Warning
  Centres at Perth, Western Australia, and Darwin, Northern Territory. 
  References to sustained winds imply a 10-minute averaging period
  unless otherwise stated.

     In the companion tropical cyclone tracks file, I occasionally
  annotate positions from warnings issued by the Joint Typhoon Warning
  Center (JTWC) of the U. S. Air Force and Navy, located at Pearl
  Harbor, Hawaii, when they differ from the Australian centres' coor-
  dinates by usually 40-50 nm or more.  The JTWC warnings are also the
  source of the 1-minute average maximum sustained wind values included
  in the tracks file.   Additionally, information describing details of
  satellite imagery and atmospheric circulation features included in
  the narratives is often gleaned from the JTWC warnings.

                 Northwest Australia/Southeast Indian Ocean
                       Tropical Activity for December

     No tropical cyclones formed in Southern Hemisphere waters between
  90E and 135E during December.  A tropical LOW formed very early in the
  month near Java and moved off to the west-southwest, passing south of
  Christmas Island as it was weakening on the 6th.  The Perth TCWC issued
  gale warnings on this LOW for a couple of days in anticipation of the
  system's developing into a tropical cyclone, but this never happened.
  Since JTWC estimated the peak winds to have reached 35 kts (1-min avg),
  I have included a brief report on TC-05S below.

     At the end of December another tropical LOW formed off the coast of
  Western Australia north of Broome which necessitated the issuance of
  gale warnings.  This LOW pursued an unusual eastward track and on the
  2nd of January intensified into Tropical Cyclone Raymond, eventually
  making landfall in the Kimberley region.  The report on Tropical Cyclone
  Raymond will be contained in the January summary.

                              TROPICAL LOW
                             2 - 7 December

     The daily STWO issued by Perth on 2 December indicated that a weak
  tropical LOW had developed in the Java Sea near the north-central coast
  of Java and had a moderate chance of strengthening into a tropical
  cyclone in about three days.    The first gale warning was issued at
  03/0400 UTC, relocating the center along the southeastern coast of Java,
  or about 450 nm east-northeast of Christmas Island.  A few hours later
  JTWC issued an interim STWO which mentioned the disturbance.  Low-level
  cloud lines were converging into a developing LLCC, and an upper-level
  analysis indicated good outflow and low vertical shear in the region.
  By 0200 UTC on the 4th deep convection had continued to increase near
  the LLCC and JTWC issued a TCFA for the LOW, which was then centered
  approximately 320 nm southeast of Jakarta, Indonesia.

     The first JTWC warning on TC-05S was issued at 04/0600 UTC.  The
  system was tracking west-southwestward at 7 kts, and this motion was
  forecast to continue under the steering influence of a low to mid-level
  anticyclone anchored to the southeast of the tropical LOW.  The system
  moved on a general west-southwesterly track throughout its short life.
  Perth maintained the MSW at 30 kts from 03/2200 UTC through 1600 UTC
  on the 5th, while JTWC assigned a peak 1-min avg MSW of 35 kts on the
  4th and 5th.  By 1800 UTC on 5 December the LOW had moved into a region
  of increased vertical wind shear and marginal SSTs.  JTWC dropped the MSW
  to 25 kts (1-min avg) and ceased to issue warnings.  Shortly afterward,
  at 05/2100 UTC, BoM Perth issued their final gale warning on the system
  which was then centered approximately 200 nm south-southeast of Christmas
  Island.  The remnant LOW continued to move west-southwestward and was
  last mentioned at 0200 UTC on 7 December when it was located about 425 nm
  southwest of Christmas Island.

     A graphic displaying the track of the tropical LOW (TC-05S) may be
  found at the following link:>

     No reports of damage or casualties resulting from this system have
  been received.

  (Report written by Gary Padgett)



  Activity for December:  No tropical cyclones


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

  Activity for December:  2 tropical depressions
                          1 tropical cyclone of gale intensity **

  ** - No warnings were issued on this system by JTWC

                        Sources of Information

     The primary sources of tracking and intensity information for
  South Pacific tropical cyclones are the warnings and advisories
  issued by the Tropical Cyclone Warning Centres at Nadi, Fiji (for
  waters north of latitude 25S), and Wellington, New Zealand (for
  waters south of latitude 25S).  References to sustained winds imply
  a 10-minute averaging period unless otherwise stated.

     In the companion tropical cyclone tracks file, I occasionally
  annotate positions from warnings issued by the Joint Typhoon Warning
  Center (JTWC) of the U. S. Air Force and Navy, located at Pearl
  Harbor, Hawaii, when they differ from the Southern Hemisphere
  centres' coordinates by usually 40-50 nm or more.  The JTWC warnings
  are also the source of the 1-minute average maximum sustained wind
  values included in the tracks file.    Additionally, information
  describing details of satellite imagery and atmospheric circulation
  features included in the narratives is often gleaned from the JTWC

                South Pacific Tropical Activity for December

     Three tropical depressions formed in the South Pacific east of 160E
  during December.  The first, designated Tropical Depression 02F by the
  Nadi, Fiji, TCWC formed on 3 December with the broad center located
  approximately 150 nm north of Port Vila, Vanuatu.   This depression was
  very slow-moving and erratic--over the next week it meandered aimlessly
  around over waters northeast of Vanuatu and northwest of Fiji.  On the
  10th it was relocated far to the east of the previous position--about
  325 nm north-northeast of Fiji.  But later the same day the center
  was shifted well back to the west to a position about 325 nm north-
  northwest of Fiji.  Obviously the disturbance was broad and poorly
  organized and likely had multiple low-level centers.   Ultimately, a
  LLCC consolidated on the 12th a few hundred miles east of northern
  Vanuatu, and Nadi commenced gale warnings due to some peripheral gales.
  TD-02F subsequently began to move southward and passed between Vanuatu 
  and Fiji on the 13th and 14th.  The system then weakened and the final 
  gale warning was issued at 14/1800 UTC, placing the center about 250 nm
  southeast of Port Vila.

     The second system, Tropical Depression 03F, formed and dissipated
  during the rather long life of Tropical Depression 02F.  TD-03F formed
  on 5 December south of Tuvalu, or about 425 nm north-northeast of Fiji.
  It subsequently moved southward to a position just east of Fiji, then
  turned east-southeastward and accelerated on the 9th.  The final bulletin
  on the system at 0900 UTC on 10 December placed the center approximately
  450 nm east of Nuku'alofa in the Kingdom of Tonga.  Tracks for both of
  these depressions can be found in the companion cyclone tracks file.

     Graphics displaying the tracks of these two tropical depressions may
  be found at the following links:>>
     The third depression, TD-04F, formed on 22 December well east of
  Tahiti and on Christmas Eve Day was named Tropical Cyclone Judy--the
  first cyclone of the 2004-2005 season in the South Pacific basin.  A
  report on Judy, written by Simon Clarke, follows.

                         TROPICAL CYCLONE JUDY
                               (TC 04F)
                            22 - 27 December

  A. Storm Origins

    An almost stationary tropical depression was analyzed by RSMC Nadi
  over French Polynesia (near 18.0S/145.0W), approximately 270 nm east of
  Tahiti, as early as 21 December 2004 (TD-04F).  The system was subject to
  significant shear as the LLCC was clearly exposed with major convection
  located to its east and south.  Aloft, TD-04F was situated to the south-
  west of the 250-hPa anticyclone and underneath an intensifying 250-hPa
  trough.  At the surface the sub-tropical ridge along 30S caused strong 
  easterly winds, inducing more cyclonic vorticity into the area.  However,
  the area of gale force winds was detached to the south and east of the 
  centre.  The SST was approximately 28 C. 

     A little over 36 hours later, the depression remained subject to
  shear, displaying baroclinic characteristics.  However, deeper convection
  began to wrap around the LLCC from the southern convective band.  By
  24/2100 UTC, gales had worked their way to the centre of TD-04F and it 
  was named Tropical Cyclone Judy, located approximately 275 nm east-
  southeast of Tahiti.

  B. Synoptic History

     At this time Judy was moving south-southwestward at about 5 kts with
  a CP of 993 hPa.  The system strengthened marginally in the ensuing
  hours (peaking at 989 hPa) and produced a broad area of gales, especially
  in the southern semi-circle.    The maximum 10-min avg winds near the
  centre were estimated to be about 40 kts.  A slight weakening in shear
  allowed a small flare up of convective activity close to the LLCC during
  Judy's life which was clearly evident in satellite imagery.   At 26/1200
  UTC Judy moved into Wellington's AOR.    However, twelve hours later
  (27/0000 UTC), increasing shear and cooler SSTs put a halt to further 
  development and Judy underwent extra-tropical transition (near
  28.5S/146.5W) and eventually merged with a low-pressure system to the
  south about 750 nm south-southeast of Tahiti soon after.

     A graphic displaying the track of Tropical Cyclone Judy may be found
  at the following link:>

  C. Meteorological Observations

     Thunderstorms from the initial depression produced some heavy rainfall
  totals in parts of French Polynesia.     The island of Takaroa at
  14.3S/145.0W received 160 mm between midnight and 24/1200 UTC, making a
  total of 356 mm there since 21/0000 UTC--well above the average December
  rainfall of 195 mm.

  D. Damage and Casualties

     No reports of damage or casualties resulting from Tropical Cyclone
  Judy have been received.

  E. Additional Discussion

     On a final note, while RSMC Nadi issued warnings on Judy, JTWC did not
  officially recognize the cyclone.  It is possible that Judy was no more 
  than a subtropical hybrid rather than a tropical cyclone.   However, as
  noted by meteorologists at Nadi, the storm packed winds of gale force 
  intensity and possibly higher around the LLCC.   Naming Judy drew public
  attention to the system during the Christmas festive season to ensure 
  that other technical/scientific issues were not down-played or ignored.
  This approach has been adopted elsewhere in the Southeast Pacific where 
  data can be difficult to obtain and the need to relay potentially life-
  saving advice is necessary: the most recent example being Tropical 
  Cyclone Epi (TCWC Port Moresby) in the Solomon Island group in June,

  (Editor's Note: Tropical Cyclone Judy was attached to a large cloud
  mass which does suggest that it was located near a baroclinic zone.
  However, the central area of the cyclone looked very much like a tropical
  cyclone.  It is interesting to note that SAB, which occasionally does
  assign subtropical ST classifications using the Hebert-Poteat scale,
  assigned Judy tropical T classifications, peaking at T2.5/2.5 on the
  24th and 25th, lending support to the idea that Judy was nominally a
  tropical cyclone.)

  (Report written by Simon Clarke)



     The purpose of this section is to list some websites where many and
  varied types of tropical cyclone information are archived.  Many readers
  will know about these already, but for the benefit of those who don't,
  I wanted to include them. 

  (1) Aircraft Reconnaissance Information

     Various types of messages from reconnaissance aircraft may be
  retrieved from the following FTP site:>

     Information regarding how to interpret the coded reconnaissance
  messages may be found at the following URL:>

  Links are also included to websites with further information about the
  U. S. Air Force 53rd Weather Reconnaissance Squadron and the NOAA Air-
  craft Operations Center.

  (2) Archived Advisories

     All the advisory products (public advisories, forecast/advisories,
  strike probabilities, discussions, various graphics) issued by TPC/NHC
  are archived on TPC's website.  For the current year (using 2004 as an
  example), the archived products can be found at:>

  Links to tropical products archives for earlier years are available at
  the following URL:>

  JTWC warnings for past storms are archived on the NRL Monterry website:>

  On the NRL site, the link to past years can be found in the upper left 
  corner of the screen.

     I am not aware at the moment of any other TCWC which archives all
  its tropical cyclone warning/advisory products for public access, but
  if I learn of any, I will add them to this list.

  (3) Satellite Imagery

     Satellite images of tropical cyclones in various sensor bands are
  available on the NRL Monterrey and University of Wisconsin websites,
  courtesy of Jeff Hawkins and Chris Velden and their associates.  The
  links are:>>

  On the NRL site, the link to past years can be found in the upper left 
  corner of the screen.  For the CIMSS site, a link to data archives is 
  located in the lower left portion of the screen.

     I'm sure there are other sites with available imagery available, and
  as I learn of them, I will add the links to this list.


                              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 August, 1998
  summary.  I don't normally include the Glossary in most months in
  order to help keep them from being too long.  If anyone would like to
  receive a copy of the Glossary, please e-mail me and I'll be happy
  to send them a copy.


  AUTHOR'S NOTE:  This summary should be considered a very preliminary 
  overview of the tropical cyclones that occur in each month. The cyclone
  tracks (provided separately) will generally be based upon operational
  warnings issued by the various tropical cyclone warning centers.  The
  information contained therein may differ somewhat from the tracking and
  intensity information obtained from a "best-track" file which is based
  on a detailed post-seasonal analysis of all available data. Information
  on where to find official "best-track" files from the various warning
  centers will be passed along from time to time.

    The track files are not being sent via e-mail.  They can be retrieved
  from the archive sites listed below.  (Note: I do have a limited e-mail
  distribution list for the track files.    If anyone wishes to receive
  these via e-mail, please send me a message.)

    Both the summaries and the track files are standard text files
  created in DOS editor.  Download to disk and use a viewer such as
  Notepad or DOS editor to view the files.

     The first summary in this series covered the month of October,
  1997.   Back issues can be obtained from the following websites
  (courtesy of Michael Bath, Michael V. Padua, Michael Pitt, Chris
  Landsea, and John Diebolt):>>>>>

     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 Annual Tropical Cyclone
  Report (ATCR) for 2004 (2003-2004 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 2004 Atlantic and Eastern North Pacific
  tropical cyclones; also, storm reports for all the 2004 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 McLeans Ridges, New South Wales,
  Australia, for assisting me with proofreading the summaries.


  Gary Padgett
  E-mail:  [email protected]
  Phone:  334-222-5327

  Kevin Boyle  (Eastern Atlantic, Western Northwest Pacific, South
                China Sea)
  E-mail:  [email protected]

  John Wallace (Assistance with Eastern North Pacific)
  E-mail:  [email protected]

  Huang Chunliang  (Assistance with Western Northwest Pacific, South
                    China Sea)
  E-mail:  [email protected]

  Simon Clarke  (Northeast Australia/Coral Sea, South Pacific)
  E-mail:  [email protected]


Document: summ0412.htm
Updated: 17th May, 2005

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