MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY

 

                                NOVEMBER, 2006

 

  NOTE FROM THE AUTHOR: Almost two years ago I began including links to

  track graphics prepared by John Diebolt of Tucson, Arizona, and archived

  on his tropical cyclone website.  A few months back John experienced a

  disk crash which resulted in a error.  He had to request assistance from

  the programmer who had written the map-generation software, but so far

  has not been able to get the problem solved.   As a convenience to users,

  I've also recently been including links to the individual tabular tracks,

  prepared by myself, which John had archived on his website.  Now, due to

  family concerns, John has not had time to place the tracks for recent

  cyclones on the website.  I have checked the websites listed at the end

  of the summaries and found that the entire November track file has been

  archived on two of them.  The links are:

 

  http://australiasevereweather.com/cyclones/2007/trak0611.htm

 

  http://www.typhoon2000.ph/garyp_mgtcs/nov06tks.txt

 

  (For general comments about the nature of these summaries, as well as

  information on how to download the tabular cyclone track files, see

  the Author's Note at the end of this summary.)

 

  *************************************************************************

 

                             NOVEMBER HIGHLIGHTS

 

   --> Eastern North Pacific unusually active for November

   --> Two intense typhoons strike Luzon--one very deadly

   --> Second South Pacific hurricane of season forms

   --> Very interesting tropical or subtropical storm forms near 40N

       in Central North Pacific

 

  *************************************************************************

 

                              ACTIVITY BY BASINS

 

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

 

  Activity for November:  No tropical cyclones

 

  *************************************************************************

 

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

 

  Activity for November:  1 tropical depression

                          1 possible tropical or subtropical storm **

                          1 tropical storm

                          1 hurricane

 

  ** - no tropical cyclone warnings issued on this system

 

 

                          Sources of Information

                          ----------------------

 

     Most of the information presented below was obtained from the

  various tropical cyclone products issued by the Tropical Prediction

  Center/National Hurricane Center (TPC/NHC) in Miami, Florida (or the

  Central Pacific Hurricane Center (CPHC) in Honolulu, Hawaii, for

  locations west of longitude 140W):  discussions, public advisories,

  forecast/advisories, tropical weather outlooks, special tropical

  disturbance statements, etc.  Some additional information may have

  been gleaned from the monthly summaries prepared by the hurricane

  specialists and available on TPC/NHC's website.  All references to

  sustained winds imply a 1-minute averaging period unless otherwise

  noted.

 

 

              Northeast Pacific Tropical Activity for November

              ------------------------------------------------

 

     Following are some statistics for the Northeast Pacific basin during

  the month of November:

 

                                      November         Average

        Parameter                       2006         1971 - 2005

        --------------------------------------------------------

        Named Storms (NS)                2               0.3

        Hurricanes (H)                   1               0.1

        Intense Hurricanes (IH)          0                0

        Named Storm Days (NSD)          6.00             1.0

        Hurricane Days (HD)             1.75             0.2

        Intense Hurricane Days (IHD)     0                0

 

     As can be seen from the above chart, overall tropical cyclone activity

  in the Northeast Pacific basin during November was greatly above the

  average for the month, being over 5 times the level normally seen during

  the month of November.  Considering just the portion of the basin lying

  east of 140W, 2006 was the first time since 1961 that two named storms

  formed in the Eastern North Pacific.  Sergio was only the fourth known

  November hurricane in the basin since at least 1960, the others being

  Tara (1961), Nora (1991), and Rick (1997).  (Hurricane Iwa formed in

  the Central North Pacific region in November, 1982.)    Had Sergio

  intensified only 5 kts more, it would have become the first November

  Category 3 hurricane in the Eastern North Pacific.  Since the beginning

  of the satellite era, only two intense hurricanes (Cat. 3+ on the Saffir/

  Simpson scale) have formed outside the June-October period:  Adolph in

  2001 and Alma in 2002, both in the month of May.  (Hurricane Ekeka in

  January-February, 1992, became an intense hurricane in the Central North

  Pacific.)

 

     Rosa was the first named November cyclone to form in the month of

  November since Tropical Storm Rosa in 2000.  Between Rosa and Sergio

  a very short-lived tropical depression (TC-20E) formed and dissipated

  on 11 November several hundred miles southwest of Manzanillo, Mexico.

  The official TPC/NHC report on this depression, as well as reports on

  all the 2006 systems, may be found at the following URL:

 

  http://www.nhc.noaa.gov/2006epac.shtml

 

     Brief reports follow on Rosa and Sergio.  Also included is a report

  on an unusual system of higher-latitude origin which formed over the

  Central North Pacific at the end of October and appeared to make the

  transition from a subtropical to tropical cyclone.

 

     Short reports with satellite pictures and small-scale maps for all

  the Northeast Pacific systems may be found at the following link:

 

  http://en.wikipedia.org/wiki/2006_Pacific_hurricane_season

 

 

 

                         POSSIBLE TROPICAL CYCLONE

                             (NRL Invest 91C)

                          30 October - 3 November

               ---------------------------------------------

 

  A. Introduction

  ---------------

 

     Every once in awhile nature throws something unexpected at us.  This

  is very true in the realm of tropical cyclones.  Since I have been

  writing these summaries for the past almost 10 years, I've had the

  privilege to cover several "firsts" in tropical cyclone climatology:

 

  (1) A fully-developed typhoon only 90 nm north of the equator--Typhoon

      Vamei near Singapore in December, 2001;

 

  (2) A tropical storm only 40 nm north of the equator and whose parent

      disturbance could be observed migrating from north of the equator

      to just south of the equator, and thence back into the Northern

      Hemisphere while maintaining a counter-clockwise circulation--

      Tropical Cyclone Agni in the Arabian Sea in November, 2004;

 

  (3) The first observed hurricane in the South Atlantic Ocean--the

      destructive Cyclone Catarina which struck Brazil in March, 2004;

 

  (4) The first known tropical cyclone to make four landfalls in

      Australia--Cyclone Steve in February-March, 2000, which practically

      circumnavigated the continent, and either as a tropical cyclone or

      during its extratropical stages, caused gales in every Australian

      state except New South Wales;

 

  (5) A fantastically active and vigorous Atlantic hurricane season which

      makes the very active seasons of 1933 and 1995 look almost tame by

      comparison and which featured four Category 5 hurricanes, including

      the lowest observed central SLP in an Atlantic hurricane--882 mb in

      Hurricane Wilma in October, 2005.

 

     In early November, another very unusual occurrence was observed in

  subtropical latitudes of the Central North Pacific ocean.   A system

  with typical subtropical cyclone characteristics formed and evolved into

  what appeared to be a tropical cyclone in an area which has always been

  considered "off limits" to tropical cyclones.  In an attempt to expedite

  the preparation of this summary, I will summarize the synoptic history

  of the system, and then follow that with some discussion gleaned from

  e-mails prompted by the storm.

 

     For the history of the storm, I am following a track and intensities

  compiled and sent by Dr. Karl Hoarau of Cergy-Pontoise University, Paris.

  NRL opened an invest on the system and numbered it '91C', so I am using

  that as an ID for the storm.

 

 

  B. Synoptic History

  -------------------

 

     Storm '91C' appeared to form in a manner similar to many subtropical

  systems seen in the North Atlantic with a cold upper-level cut-off LOW

  moving over relatively "warm" SSTs of around 20 C coincident with the

  first appearance of a closed surface LOW and with the warm lower-level

  core supported by convection.  (This information from Mark Guishard,

  Director of the Bermuda Weather Surface.)  Based upon Karl's track, a

  25-kt LOW with subtropical characteristics was located approximately

  1000 nm northeast of Honolulu, Hawaii, at 0600 UTC on 30 October.

  The LOW initially moved eastward, gradually curving to the northeast.

  By 1200 UTC on 31 October '91C' had reached a position near 39.8N/142.4W

  and had taken on a more tropical appearance with an eye feature visible.

  At this juncture the system curved rather sharply back to the north-

  northwest and by early on 1 November was moving almost due westward.

 

     At 1200 UTC on 1 November '91C' had reached a point approximately

  1400 nm northeast of Honolulu.  An eye was clearly visible and convection

  was deepest around this time.  Karl estimates that the system reached

  a peak intensity of 55 kts at 1200 UTC before beginning to slowly weaken.

  After 01/1800 UTC the storm turned abruptly to the southeast and then

  eastward, completing a counter-clockwise loop shortly after 02/0600 UTC.

  The eye was still visible at this time, but shortly thereafter shear

  increased and convection began to quickly disappear.  The LOW began to

  rapidly weaken as it accelerated to the east-northeast.  The final entry

  in Karl's track places a 30-kt non-convective remnant LOW about 450 nm

  west of Coos Bay, Oregon, around 0000 UTC on 3 November.

 

     Since no operational warnings were issued for this system (except

  for marine warnings issued by OPC), I have included below the track

  for '91C' which I prepared for the companion global cyclone tracks

  file:

 

  Storm Name: None                  Cyclone Number: None    Basin: NEP

  (NRL Invest - 91C / System was a subtropical/possible tropical cyclone)

 

     Date   Time   Lat      Lon    Cent  MSW   MSW        Remarks

            (GMT)                 Press 1-min 10-min

                                   (mb) (kts) (kts)

  -------------------------------------------------------------------------

 

  06 OCT 30 0600  36.0 N  149.1 W         25        Subtropical

  06 OCT 30 1200  35.7 N  147.7 W         25

  06 OCT 30 1800  36.6 N  145.4 W         30

  06 OCT 31 0000  37.6 N  143.8 W         35

  06 OCT 31 0600  38.5 N  142.9 W         45        Eye feature/more trop.

  06 0CT 31 1200  39.8 N  142.4 W         40

  06 OCT 31 1800  40.9 N  142.8 W         45

  06 NOV 01 0000  42.2 N  143.5 W         45        Eye visible

  06 NOV 01 0600  42.8 N  144.7 W         50

  06 NOV 01 1200  42.9 N  145.9 W         55        Deepest convection

  06 NOV 01 1800  42.5 N  146.4 W         50

  06 NOV 02 0000  41.8 N  145.7 W         50

  06 NOV 02 0600  41.7 N  143.8 W         50        Eye still visible

  06 NOV 02 1200  42.0 N  140.3 W         45

  06 NOV 02 1800  42.5 N  137.7 W         35        Sheared

  06 NOV 03 0000  43.5 N  134.5 W         30        Convection absent

 

  Note: The positions, intensities and comments above were kindly provided

  by Dr. Karl Hoarau of Cergy-Pontoise University, Paris.  A special thanks

  to Karl for creating a track for this interesting system.

 

 

  C. Additional Discussion

  ------------------------

 

     Disturbance '91C' was not entirely without historical precedent, rare

  though it was.  In late August/early September, 1975, a tropical cyclone

  was tracked at fairly high latitudes in the Central North Pacific,

  becoming a tropical storm at 32.0N/159.0W and reaching hurricane

  intensity at 40.0N/156.0W.   The Eastern North Pacific seasonal summary

  prepared by the staff of the former Eastern Pacific Hurricane Center

  in San Francisco noted that there was a possibility that the hurricane

  formed from the remnants of Eastern Pacific Hurricane Ilsa, which had

  dissipated as a tropical cyclone several days earlier well east of 140W.

  Since the Central Pacific storm was not named, likely no operational

  warnings were issued, except for perhaps ordinary marine warnings.  It

  is not known to the author exactly when this system was added to the

  Eastern/Central North Pacific "best tracks" database.

 

     With systems of this nature there is always a fair amount of

  discussion generated regarding its nature and classification.  Clark

  Evans of the Department of Meteorology at Florida State University notes

  that the cyclone phase space from the various model solutions were in

  good agreement on the thermal structure of the cyclone, that being a

  reasonably symmetric low-level warm core and a neutral thermal structure

  aloft--consistent with a subtropical storm or possibly a shallow tropical

  cyclone.   Mark Guishard of the Bermuda Weather Service was of the

  opinion that by 2 November the system had undergone tropical transition.

  Mark Lander noted that cloud tops in '91C' were between 35,000 and 40,000

  feet with temperatures between -42 and -53 C.  In Mark's opinion this

  system was not very different from some of the tropical cyclones seen in

  the Atlantic the previous season, Hurricane Vince in particular.

 

     There were a couple of obs associated with '91C' worth mentioning.

  According to Derrick Herndon of CIMSS, a number of buoys in the region

  indicated a very large area of SLPs below 1000 mb.  The center appeared

  to pass within 45 nm of buoy 46637 which reported a pressure of 989 mb

  (no winds from the buoy) at 01/1300 UTC.  This represented a drop of

  10 mb in 13 hours.  Since the center was about 36 nm to the south at

  the time of the observation, the pressure could have been a little lower.

  Mark Lander noted that a QuikScat pass at approximately 0400 UTC on

  2 November depicted winds of at least 45 kts within the storm.

 

  (Report written by Gary Padgett)

 

 

 

                            TROPICAL STORM ROSA

                                 (TC-19E)

                              8 - 10 November

                  ---------------------------------------

 

     Tropical Storm Rosa was the first Eastern North Pacific tropical

  storm to form in the month of November since 2000.  (The 2000 storm,

  coincidentally, was also named Rosa.)  Rosa's progenitor seems to have

  been a tropical wave which left the west coast of Africa on 22 October.

  The wave remained weak while crossing the Atlantic, but after crossing

  into the Pacific on 3 November, convective activity began to increase.

  A broad low-pressure area formed several hundred miles south of the Gulf

  of Tehuantepec on the 5th.  Convection remained disorganized for a day

  or so, but began to increase on the 7th and Dvorak classifications were

  begun.   Deep convection significantly increased shortly after 0000 UTC

  on 8 November and the system was upgraded to Tropical Depression 19E

  at 0600 UTC while located about 385 nm south of Manzanillo, Mexico.

 

     The system moved slowly northwestward throughout its existence and

  was hampered by southwesterly shear.  Although it appeared weaker later

  on the 8th, convection re-formed near the center early on 9 November

  and it was upgraded to Tropical Storm Rosa at 0600 UTC while centered

  about 260 nm south-southwest of Manzanillo.  However, further intensi-

  fication was halted by the strong shear and Rosa remained a minimal

  tropical storm for only 18 hours.  The storm weakened into a tropical

  depression at 10/0000 UTC and became an open trough later that day

  about 215 nm southwest of Manzanillo.

 

     No damage or casualties are known to have resulted from Tropical

  Storm Rosa.

 

     This report is largely based upon the official TPC/NHC storm report,

  authored by Daniel P. Brown.  The report can be accessed at:

 

  http://www.nhc.noaa.gov/2006epac.shtml

 

 

 

                              HURRICANE SERGIO

                                  (TC-21E)

                              14 - 20 November

                    ------------------------------------

 

     Hurricane Sergio was the strongest Eastern North Pacific hurricane

  for so late in the season, and was the longest-lasting November tropical

  cyclone on record for the basin.  A tropical wave crossed southern

  Central America and entered the Eastern Pacific on 7 November.  An area

  of associated showers and cloudiness moved slowly westward for several

  days.  By 12 November convective activity became more concentrated

  over an area roughly 350 nm to the south of Acapulco, Mexico, and Dvorak

  classifications were initiated.   The system had developed sufficient

  organization by 1800 UTC on 13 November to be designated as Tropical

  Depression 21E while centered about 400 nm south of Manzanillo, Mexico.

 

     The storm initially moved northwestward, but soon stalled while

  strengthening into Tropical Storm Sergio on the 14th.   Sergio then

  turned toward the southeast, apparently due to the flow associated with

  a mid to upper-level trough to its northeast, while continuing to

  intensify.  The storm became a hurricane on 15 November while situated

  within a favorable environment of light vertical shear, anticyclonic

  outflow aloft, and a generally moist troposphere.  Hurricane Sergio

  quickly strengthened, reaching its peak intensity of 95 kts around

  15/1800 UTC, exhibiting a very small and distinct eye.  After peaking

  in intensity, Sergio turned toward the northeast and then north-northeast

  and began to weaken as westerly shear increased over the cyclone.  By

  early on 17 November the LLCC had become partially-exposed on the western

  side of the circulation and the hurricane was downgraded to a tropical

  storm at 17/0600 UTC.   Over the next few days high pressure built to

  the north and northeast of Sergio and it meandered around in several

  directions, ultimately moving to the west-southwest.  Deep convection

  re-formed near the center on the 18th and Sergio re-intensified

  slightly, but the weakening trend soon resumed and the storm had weakened

  into a tropical depression by 20/0000 UTC.  Later that day the cyclone

  dissipated about 300 nm southwest of Manzanillo as the LLCC became

  elongated along a cyclonic shear axis.

 

     No damage or casualties are known to have resulted from Hurricane

  Sergio.

 

     This report is largely based upon the official TPC/NHC storm report,

  authored by Richard J. Pasch and David P. Roberts.  The report can be

  accessed at:

 

  http://www.nhc.noaa.gov/2006epac.shtml

 

  *************************************************************************

 

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

 

  Activity for November:  1 subtropical storm **

                          1 typhoon

                          1 super typhoon

 

  ** - no tropical cyclone warnings issued on this system

 

 

                          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

  Philippines' Atmospheric, Geophysical & Astronomical Services

  Administration (PAGASA).  A very special thanks to Michael for the

  assistance he so reliably provides.

 

      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 November

              ------------------------------------------------

 

     As the month of November opened, Typhoon Cimaron was spinning in the

  South China Sea after striking northern Luzon as a super typhoon.   The

  storm subsequently began to weaken as it drifted around in the Sea and

  had dissipated by the 6th.  The complete report on Typhoon Cimaron

  (known as Typhoon Paeng in the Philippines) may be found in the October

  summary.

 

     Two other major typhoons formed during the month, and like their

  immediate predecessor, struck the Philippines as strong typhoons.  The

  first, Typhoon Chebi/Queenie, followed a path across northern Luzon very

  similar to that taken by Cimaron/Paeng.  Like the earlier storm, Chebi

  was rather small and made landfall in a fairly unpopulated area and

  did not leave behind a large loss of life.  Super Typhoon Durian/Reming,

  however, followed a more southern track across southern Luzon and was

  very deadly, being responsible for more than 700 fatalities.  Reports on

  these two typhoons, authored by Kevin Boyle, follow.

 

     A short report is also included on a system which appeared to be a

  subtropical storm early in the month over waters between Wake Island

  and the Dateline.

 

     The online Wikipedia reports for the Northwestern Pacific cyclones may

  be accessed at the following URL:

 

  http://en.wikipedia.org/wiki/2006_Pacific_typhoon_season

 

 

 

                         POSSIBLE SUBTROPICAL CYCLONE

                               (SAB Invest 99W)

                                6 - 9 November

               ------------------------------------------------

 

     A cyclonic system in the eastern portion of the Northwest Pacific

  basin in early November received Dvorak tropical classifications and

  subtropical classifications based on the Hebert-Poteat method by SAB.

  This system appeared to be a rather typical subtropical storm which

  formed from an occluded cyclone.  JMA began issuing gale warnings for

  the system at 0600 UTC on 6 November when the system was located about

  900 nm northeast of Wake Island.  Late on the 6th QuikScat data was

  received indicating winds of 45-50 kts.  SAB initiated Hebert-Poteat

  classifications on the system at 06/2030 UTC.  The agency requested

  JTWC to open a formal invest number for the system, but JTWC refused

  to do so.  Therefore, SAB applied the number '99W' to the cyclone

  in all their bulletins.

 

     The system moved slowly in a generally southwestward direction.

  By 07/2030 UTC, at which time SAB assigned a ST3.0 rating, the center

  was located about 875 nm northeast of Wake Island.  The winds began

  to slowly weaken throughout the 7th and 8th.  At 07/2030 UTC, SAB

  began classifying the system using Dvorak tropical T-numbers, rendering

  a T2.5/2.5.   By 2030 UTC on 8 November '99W' had reached a point

  about 500 nm northeast of Wake Island and SAB's Dvorak estimate had

  dropped to T1.5/2.0, and based on the JMA High Seas Bulletins, winds

  had dropped below gale force.  JMA continued to track the weakening

  system southwestward, finally dropping it after 1800 UTC on the 9th

  when it was located about 200 nm east-northeast of Wake Island.

 

     Karl Hoarau expressed the opinion that the system was not a tropical

  cyclone, but rather a typical subtropical storm.  David Roth of HPC

  reported that the cyclone phase space based on the GFS showed '99W' as

  a shallow, symmetric warm-core system, which is consistent with a

  subtropical storm.   David noted that on 7 November, when the cyclone

  was located over 23-24 C SSTs, that thunderstorms had broken out on

  the northern side of the center and that the depth of convection was

  greater than what was typical for an occluded cyclone.

 

     Since no operational warnings were issued for this system (other than

  the JMA warnings), I have included below the track I prepared for '99W'

  for the companion global cyclone tracks file:

 

  Storm Name: None                  Cyclone Number: None    Basin: NWP

  (SAB Invest - 99W / System was likely a typical subtropical cyclone)

 

     Date   Time   Lat      Lon    Cent  MSW   MSW        Remarks

            (GMT)                 Press 1-min 10-min

                                   (mb) (kts) (kts)

  -------------------------------------------------------------------------

 

  06 NOV 06 0600  33.0 N  173.0 E  1002         35  JMA warnings

  06 NOV 06 1200  32.0 N  174.0 E  1004         35

  06 NOV 06 1800  32.0 N  175.0 E  1000         40

  06 NOV 06 2030  31.6 N  175.2 E  1000   50    40  SAB satellite bulletins

  06 NOV 07 0230  31.2 N  175.5 E  1000   50    45  ST3.0

  06 NOV 07 0830  30.8 N  175.7 E  1000   45    45  ST2.5

  06 NOV 07 1430  30.1 N  176.5 E  1000   45    45  ST3.0

  06 NOV 07 2030  29.7 N  176.1 E  1000   40    45  T2.5/2.5

  06 NOV 08 0230  28.6 N  175.6 E  1000   40    45  T2.5/2.5  

  06 NOV 08 0830  27.6 N  175.2 E  1004   35    40  T2.0/2.5

  06 NOV 08 1430  26.3 N  174.2 E  1006   35    35  T2.0/2.5

  06 NOV 08 2030  25.0 N  173.2 E  1006   30    30  T1.5/2.0

  06 NOV 09 0000  24.0 N  173.0 E  1006         25  JMA bulletins

  06 NOV 09 0600  23.0 N  172.0 E  1006         25

  06 NOV 09 1200  22.0 N  171.0 E  1006         25

  06 NOV 09 1800  20.0 N  170.0 E  1008         20

 

  Note: I asked Karl Hoarau for his opinion of this system, and he stated

  that he regarded it as subtropical only.  However, out of respect for the

  SAB analysts who assigned Dvorak tropical classification numbers for part

  of the cyclone's history, I have attempted to create a track.  At the

  time of the first SAB satellite bulletin on 6 November there was Quik-

  Scat data available supporting winds of 45-50 kts.  After this point the

  1-min avg MSW values given in the table above are my own estimates based

  on the SAB classifications.  The 10-min avg MSW values, as usual for the

  NWP basin, are taken from JMA's High Seas Bulletins.

 

  (Report written by Gary Padgett)

 

 

 

                               TYPHOON CHEBI

                        (TC-23W / TY 0620 / QUEENIE)

                              8 – 14 November

              ------------------------------------------------

            

  Chebi: contributed by South Korea, is a swallow – a small bird with

         long wings and a forked tail which eats insects.  Each spring

         the bird visits Korea where it is believed to bring good fortune.

 

  A. Introduction and Storm Origins

  ---------------------------------

 

     Typhoon Chebi was the third of six tropical cyclones to affect the

  Philippines and followed an almost identical track across Luzon as its

  predecessor, Super Typhoon Cimaron.  On approach to Luzon, the storm

  underwent explosive deepening on 10 November, intensifying from 55 kts

  to 115 kts in just six hours!  Typhoon Chebi briefly peaked at 125 kts

  before coming ashore near Casiguran early on 11 November with a MSW of

  around 105 kts.  After transiting the northern Philippines, Chebi

  continued to steadily weaken in the South China Sea, succumbing to high

  wind shear and dry air on 14 November.  

 

     At 0130 UTC 8 November JTWC issued a STWO with ‘fair’ development

  potential for a disturbance located approximately 420 nm west-northwest

  of Guam.  Both multi-spectral imagery and a 07/2251 UTC SSMI pass

  revealed increased convection over a consolidating LLCC.  Upper-level

  analysis indicated favourable divergence aloft with low to moderate

  wind shear.  The system entered PAGASA’s area of responsibility at

  08/1200 UTC and the agency assigned the name Queenie.  (JMA had begun

  issuing advisories six hours earlier.)  Based on continued development

  and improving poleward outflow, JTWC issued a TCFA at 08/1100 UTC,

  followed by issuance of the first warning on Tropical Depression 23W

  at 09/0000 UTC.  The Prognostic Reasoning issued at this time noted

  that a closed circulation was not evident on a recent QuikScat pass,

  but multi-spectral satellite imagery indicated westerly winds on the

  southern periphery of TD-23W wrapping into a LLCC.  Moving westwards,

  TD-23W was upgraded to Tropical Storm Chebi by JMA and JTWC at 09/1200

  UTC with 10-min avg and 1-min avg MSWs of 35 kts and 45 kts,

  respectively.

 

 

  B. Synoptic History

  -------------------

 

     Tropical Storm Chebi tracked westwards south of a well-established

  subtropical ridge which placed Luzon, Philippines, once again in the

  firing line, having being mauled by Super Typhoon Cimaron almost two

  weeks earlier.  By 10/0000 UTC Chebi had strengthened to 55 kts, but what

  transpired during the next six hours was truly remarkable!  Tropical

  Storm Chebi underwent explosive intensification to such an extent that

  JTWC upgraded the tropical cyclone to a 115-kt typhoon at 10/0600 UTC. 

  The estimated CP (analysed by JMA) dropped 40 mb during that six-hour

  period from 985 mb to 945 mb.  Continuing steadily westwards, Typhoon

  Chebi/Queenie reached its maximum intensity of 125 kts at 10/1200 UTC

  while located approximately 150 nm north of Catanduanes Island.  The

  storm was a tight, compact system with typhoon-force winds extending to

  around 35 nm and gales as far as around 100 nm.  The tropical cyclone

  began to weaken as it approached the eastern coast of Luzon .

 

     Typhoon Queenie made landfall over eastern Luzon near Casiguran at

  0000 UTC 11 November with the MSW estimated at 105 kts.  The cyclone

  crossed the island of Luzon in twelve hours and entered the South China

  Sea at 11/0600 UTC.  Although poleward outflow remained good, Typhoon

  Chebi continued to atrophy as it headed into an area of cool, dry air and

  higher wind shear.  JMA downgraded Chebi to a 55-kt tropical storm at

  12/0600 UTC while JTWC maintained typhoon intensity for another twelve

  hours before lowering their MSW to 60 kts.  Tropical Storm Chebi began

  to meander more northwestwards on 13 November as a weakness developed

  in the subtropical ridge.  Deep convection became confined to the

  northern quadrants as moderate southerly wind shear persisted.  JMA

  lowered Chebi to tropical depression intensity at 14/0600 UTC, ending

  bulletin transmission.  JTWC downgraded Chebi to a 25-kt tropical

  depression on their final warning at 14/1200 UTC, placing the centre

  80 nm east-southeast of Hainan, China.

 

     JMA estimated a maximum intensity of 105 kts (10-min avg) and a

  minimum CP of 925 mb at 10/1200 UTC.  PAGASA estimated a peak 10-min avg

  MSW of 105 kts at 10/1200 UTC and 10/1800 UTC during the period the

  storm was within their AOR.

 

 

  C. Damage and Casualties

  ------------------------

 

     News reports indicate one person was killed in the Philippines, eight

  injured, and three others missing.  The storm brought down power lines,

  felled trees, and triggered floods and landslides.  Strong winds

  destroyed two houses and damaged a dozen others in Casiguran.  There

  were no other reports of damages in the Philippines.

 

 

  D. Additional Discussion

  ------------------------

 

     While there can be no doubt that Chebi/Queenie intensified very

  rapidly on 10 November, it may not have strengthened quite as much as

  implied by the JTWC warnings.   Karl Hoarau has provided an estimate

  of Chebi's intensity on 9 and 10 November, and following is a table

  comparing Karl's estimate with JTWC's:

 

   Date  Time    JTWC    KH

          (Z)    (kt)   (kt)

  --------------------------

  09 NOV 0000     25     35

  09 NOV 0600     30     40

  09 NOV 1200     45     50

  09 NOV 1800     45     60

  10 NOV 0000     55     70

  10 NOV 0600    115    115

  10 NOV 1200    125    135

 

     An intensification of 45 kts in six hours is still truly remarkable,

  even if not quite as extreme as 60 kts.  JMA's 10-min avg estimate at

  10/0000 UTC was 55 kts, which, all other things being equal, would be

  roughly equivalent to a 1-min avg MSW of 65 kts, which lends a little

  support to Karl's estimate.  Also, Mark Lander expressed the opinion

  that JTWC's 10/0000 UTC MSW of 55 kts was too low.

 

     One other point--in the track file I stuck with JTWC's peak intensity

  of 125 kts.  This is supported by the peak Dvorak ratings of T6.5/6.5

  from JTWC, SAB and AFWA--none went as high as T7.0.  A delta of 10 kts

  is not really significant at those windspeeds, but Karl's peak of 135 kts

  would, of course, place Chebi in the super typhoon category.

 

  (Sections A, B and C written by Kevin Boyle; Section D by Gary Padgett)

 

 

 

                           SUPER TYPHOON DURIAN

                        (TC-24W / TY 0621/ REMING)

                         25 November – 7 December

              ----------------------------------------------

 

  Durian: contributed by Thailand, is a favourite fruit of Thailand

          (Durio Zibethinus)

 

  A. Introduction and Storm Origins

  ---------------------------------

 

     The sixth and final super typhoon of 2006, Durian was also the fifth

  tropical cyclone to hammer the Philippine Archipelago, striking Luzon

  further to the south than its predecessors, Cimaron and Chebi.  Durian

  had a fairly long track, originating from a disturbance south of the

  Marianas, passing through the Philippines, and ending in the Gulf of

  Thailand after skirting Vietnam.  Typhoon Durian left 734 people dead

  in the Philippines and killed 81 in Vietnam.

 

     Based on the persistence of deep convection, the tropical disturbance

  that spawned Super Typhoon Durian was initially discussed in JTWC’s

  STWO at 0600 UTC 24 November when it was located approximately 120 nm

  southeast of Chuuk.  Animated multi-spectral satellite imagery and a

  23/1932 UTC QuikScat pass both revealed a broad area of low to mid-

  level cyclonic turning.  The system was situated in an area of moderate

  wind shear with good polar outflow aloft associated with an upper-level

  anticyclone.  Once the vertical wind shear relaxed and convection began

  to wrap into a better-defined LLCC, JTWC raised the development

  potential to ‘fair’ at 25/0600 UTC, the same time that JMA first

  identified a weak tropical depression in their shipping bulletins.  The

  first warning issued by JTWC at 25/1800 UTC placed the centre of the

  newly-formed tropical depression (TD-24W) approximately 450 nm east of

  Yap and 280 nm south of Guam.  Drifting westwards, TD-24W intensified,

  and was upgraded to a 35-kt tropical storm in JTWC’s second warning at

  26/0000 UTC.    Six hours later, JMA raised their MSW to 35 kts,

  assigning the name Durian.

 

 

  B. Synoptic History

  -------------------

 

     Tropical Storm Durian gradually strengthened over the next two days as

  it moved west to west-northwestward under the influence of a low to

  mid-level ridge situated to the north. This was the same synoptic

  feature that had steered Typhoon Chebi across the northern Philippines a

  week earlier.  PAGASA began issuing bulletins on the storm, naming it

  Reming, at 28/0000 UTC after the tropical cyclone entered that agency’s

  AOR.  Tropical Storm Durian/Reming was upgraded to a 65-kt typhoon (per

  JTWC’s warnings) at 28/1200 UTC while centred approximately 640 nm east

  of Manila, Philippines.  JMA raised their MSW to 70 kts six hours

  later.  Typhoon Durian/Reming rapidly intensified and reached its peak

  strength as a 135-kt super typhoon at 29/1200 UTC approximately 325 nm

  east-southeast of Manila.  The storm made landfall in the Bicol region

  after passing over Catanduanes Island at around 0600 UTC 30 November

  with the MSW estimated at 125 kts.  Reming weakened over land as it

  tracked westward over Luzon and emerged into the South China Sea on

  1 December.

 

     Typhoon Durian/Reming continued to slowly weaken as it transited

  westwards across the South China Sea on 1 December.  After the MSW had

  bottomed out at 75 kts, the tropical cyclone began to strengthen again

  and attained a secondary peak of 90 kts at 03/0000 UTC while centred

  approximately 290 nm east-northeast of Nha Trang, Vietnam.  Increasingly

  influenced by the northeast monsoon, Durian began to drift towards the

  west-southwest on 3 December and began to deteriorate in the face of

  higher wind shear and cooler air.  After turning southwestwards early on

  4 December, Durian was downgraded to a 50-kt tropical storm at 04/0600

  UTC.  However, it briefly re-attained minimal typhoon strength at

  04/1800 UTC before JTWC lowered the MSW back to tropical storm status

  at 05/0600 UTC.  At this time Durian was scraping along the southern

  shoreline of Vietnam.  JTWC downgraded it to tropical depression status

  at 05/1800 UTC with the issuance of their final bulletin.  JMA issued

  their final statement at 05/1200 UTC.   The remnant LOW subsequently

  crossed over the Malay Peninsula into the Andaman Sea where it finally

  dissipated.

 

     JMA estimated a maximum intensity of 105 kts (10-min avg) and a

  minimum CP of 915 mb.  During the time Typhoon Reming was within PAGASA's

  AOR, the peak 10-min avg MSW assigned by that agency was 105 kts at

  29/1200 UTC.

 

     According to some information sent by Karl Hoarau, the Virac station

  (13.6N/124.2E) recorded a SLP of 941.4 hPa with a MSW of 65 kts (10-min

  avg) on 30 November at 0200 UTC when the centre of the eye was located

  approximately 15 nm to the south-southeast.    The peak gust recorded

  at the station, around 0300 UTC, was 143 kts.

 

 

  C. Damage and Casualties

  ------------------------

 

     The latest NDCC figures indicate that at least 734 people were killed

  with 762 persons still missing.  Damage from Typhoon Durian/Reming is

  estimated at over US$ 103 million.  The storm passed over the Mayon

  volcano where mudslides of volcanic ash and boulders covered a large

  portion of Legazpi City with deep mud.  According to the Wikipedia online

  report, at least 81 people died in Vietnam with 16 missing as a result of

  Durian.

 

  (Report written by Kevin Boyle)

 

  *************************************************************************

 

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

 

  Activity for November:  No tropical cyclones

 

 

              North Indian Ocean Tropical Activity for November

              -------------------------------------------------

 

     November is the month most likely to see tropical cyclone activity

  in the North Indian Ocean, averaging 1.45 tropical storms and 0.73

  hurricanes over the period 1981-2002.  However, November of 2006 proved

  to be a quiet month in the basin with not a single depression classified

  by any warning agency.  The only system of note occurred over the west-

  central Arabian Sea around 24-25 November.  A disturbed area which had

  formed around 19 November was located on the 20th about 600 nm south-

  west of Mumbai (Bombay), India.  The disturbance appeared to slowly

  migrate westward but, unfortunately I do not have available the STWOs

  issued by JTWC on 23 and 24 November.   At 24/2030 UTC JTWC issued a

  satellite bulletin, ostensibly for the same disturbance, which placed

  a LLCC near 9.6N/57.5E with a Dvorak rating of T2.5/2.5.   The intensity

  estimates, however, began to drop after this and to my knowledge, no

  TCFA was issued for this system. 

 

  *************************************************************************

 

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

 

  Activity for November:  1 tropical storm

 

 

                            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 Tropical Cyclone Advisory Centres in Mauritius and

  Madagascar with longitude 55E being the demarcation line between their

  respective areas of naming 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 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 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 November

            -----------------------------------------------------

 

     One tropical storm formed in the Southwest Indian Ocean west of 90E

  during November--Tropical Storm Anita.  Anita was a minimal tropical

  storm which moved southward through the Mozambique Channel.  A report

  on this system follows.

 

     Short reports with satellite pictures and small-scale maps for all

  the Southern Hemisphere systems may be found at the following link:

 

  http://en.wikipedia.org/wiki/2006-07_Southern_Hemisphere_tropical_cyclone_season

 

 

 

                           TROPICAL STORM ANITA

                             (MFR-02 / TC-03S)

                         26 November - 3 December

               --------------------------------------------

 

  A. Introduction and Storm Origins

  ---------------------------------

 

     Tropical Storm Anita was the first named tropical storm of the 2006-

  2007 tropical cyclone season in the Southwest Indian Ocean basin.  The

  storm was a relatively weak system which formed deep in the tropics well

  to the north of Madagascar and, during its tropical storm phase, pursued

  a generally southerly track down the middle of the Mozambique Channel.

  A satellite bulletin issued by JTWC at 1800 UTC on 26 November was the

  first reference to the disturbance which became Anita.  The LOW, with

  winds estimated at around 25 kts, was located approximately 500 nm east

  of Zanzibar.  By early on the 27th deep convection was consolidating

  over a LLCC, and JTWC assessed the development potential as 'fair' in

  an interim STWO issued at 27/0230 UTC.     MFR initiated bulletins on

  Tropical Disturbance 02 at 2700 UTC.  The system was located within a

  region of moderate vertical shear with an anticyclone to its south.

 

     Dvorak estimates from AFWA and JTWC had begun at T1.5/1.5, but by

  around 28/0000 UTC had reached T2.0/2.0.  Also, MFR's ratings had

  reached T2.0/2.0 by the same time, implying 10-min avg winds of 25 kts.

  The disturbance at this time was moving southwestward toward the northern

  end of the Mozambique Channel.   Deep convection decreased some on the

  28th, but by 29/0000 UTC was increasing over the LLCC with bands wrapping

  into the center on the northern and southern peripheries of the system.

  An anticyclone aloft was contributing to good poleward outflow and

  low vertical shear.  At 29/0030 UTC JTWC issued a TCFA, followed by the

  first warning on TC-03S at 1200 UTC.   The first JTWC warning located

  the center about 425 nm west-northwest of the northern tip of the island

  of Madagascar, tracking southwestward at about 4 kts.  The initial MSW

  was set at 40 kts (1-min avg).  MFR's intensity estimate was still at

  25 kts, but was upped to 30 kts (i.e., tropical depression status) six

  hours later.  The system was forecast to track generally southward along

  the western periphery of a steering ridge anchored northeast of

  Madagascar.

 

 

  B. Synoptic History

  -------------------

 

     JTWC upped the MSW in TC-03S to 45 kts in their second warning issued

  at 0000 UTC on 30 November; however, the official intensity from MFR

  remained at 30 kts for more than another day.  The storm continued

  moving slowly south-southeastward through the Mozambique Channel on the

  last day of November.  Satellite imagery around 0000 UTC on 1 December

  showed that the center was starting to decouple from the deep convection

  and was located on the northern edge of the deepest convection. 

  Accordingly, JTWC lowered their MSW estimate to 40 kts (1-min avg). 

  Interestingly, it was at this time that the Meteorological Services of

  Madagascar upgraded the depression to tropical storm intensity and

  assigned the name Anita, which was contributed to the regional list by

  themselves.  At 01/0000 UTC the center of Tropical Storm Anita was

  located about 375 nm northwest of Antananarivo, Madagascar, and moving

  toward the south-southeast at 8 kts.  The MSW was estimated at 35 kts by

  MFR (10-min avg), which turned out to be the peak intensity assigned by

  that agency.

 

     Anita made a slight comeback later on 1 December with JTWC bumping

  the intensity back up to 45 kts at 1200 UTC.  Vertical wind shear was

  moderate, but upper-level outflow was good.  By late on the 1st, however,

  vertical shear had increased to the point that most of the associated

  deep convection had dissipated.  JTWC issued their final warning on

  Anita at 02/0000 UTC, lowering the winds to 30 kts.  At the same time

  MFR also downgraded Anita to a 30-kt depression.  The ex-tropical storm

  continued slowly southward in the Channel, turning more to the southwest

  by 02/1800 UTC.   By then MFR had downgraded the depression to a 25-kt

  tropical disturbance, and the final bulletin at 03/0600 UTC placed a

  weak 20-kt LLCC about 350 nm west of Antananarivo, although winds of

  25-30 kts were still occurring in some of the stronger squalls in the

  southern semicircle.

 

 

  C. Damage and Casualties

  ------------------------

 

     No damage or casualties are known to have resulted from moderate

  Tropical Storm Anita.

 

  (Report written by Gary Padgett)

 

  *************************************************************************

 

  NORTHWEST AUSTRALIA/SOUTHEAST INDIAN OCEAN (AUW) - From 90E to 135E

 

  Activity for November:  No tropical cyclones

 

  *************************************************************************

 

  NORTHEAST AUSTRALIA/CORAL SEA (AUE) - From 135E to 160E

 

  Activity for November:  No tropical cyclones

 

  *************************************************************************

 

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

 

  Activity for November:  2 tropical depressions **

                          1 tropical cyclone of hurricane intensity

 

  ** - one of these treated as a minimal tropical storm 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

  warnings.

 

 

                 South Pacific Tropical Activity for November

                 --------------------------------------------

 

     Just about exactly a month after intense Tropical Cyclone Xavier had

  given a very early start to the 2006-2007 cyclone season in the South

  Pacific, another cyclone of hurricane intensity formed southeast of the

  Solomon Islands.    Tropical Cyclone Yani became an impressive 75-kt

  hurricane but didn't quite match the earlier Xavier's 95-kt winds.

  The cyclone meandered around over waters south of the Solomons and well

  to the northwest of Vanuatu without significantly affecting any islands.

  A report on Tropical Cyclone Yani, written by Simon Clarke, follows.

 

     Two other systems were designated tropical depressions by RSMC Nadi,

  Fiji.  The first, Tropical Depression 03F, was a fairly weak system which

  was first analyzed as a depression at 0600 UTC on 1 November when it was

  located near 12.9S/179.2E, or well northeast of Fiji.  At 2100 UTC the

  center was re-analyzed to be much farther west near 12.7S/173.9E, or

  far to the northwest of Fiji.  The system meandered around in the same

  general area for a couple days in an environment of moderate vertical

  shear and was never forecast to develop into a tropical cyclone by the

  global models.  Winds likely never exceeded 20-25 kts and no track was

  included for this system in the companion cyclone tracks file prepared

  by the author.

 

     The other system, Tropical Depression 05F, formed at the end of the

  month to the northeast of the Solomons and strengthened to the point

  that JTWC classified it as a minimal tropical storm (1-min avg) and

  designated it as TC-04P.  A short report on this system is included

  below.

 

     Short reports with satellite pictures and small-scale maps for all

  the Southern Hemisphere systems may be found at the following link:

 

  http://en.wikipedia.org/wiki/2006-07_Southern_Hemisphere_tropical_cyclone_season

 

 

 

                          TROPICAL CYCLONE YANI

                            (TD-04F / TC-02P)

                             17 – 27 November

                -----------------------------------------

 

     Tropical Cyclone Yani was the second early season cyclone in the

  South Pacific to emerge from the persistently active ITCZ stretching

  from the Solomon Islands through to the Northern Cook Islands during

  the months of October and November, 2006.

 

     The initial tropical depression (04F) was first identified as

  early as 16 November as a westward-moving disturbance to the west of

  the International Date Line near 5.0S/174.0E.  However, TD-04F was

  slow to consolidate despite a well-established westerly monsoonal

  flow to the north and a strong southeasterly wind surge working its

  way into the depression from the south.  By 19 November, TD-04F had

  all but stalled to the SE of Rennell Island while describing a

  shallow clockwise loop.  It was not until 21/1900 UTC that the system

  commenced consistent central convective consolidation near 11.6S/161.6E.

  At this time, TD-04F had moved under the 250-hPa ridge in an area of

  weak wind shear and thereby entered an environment favourable for

  further development.  Convection erupted around the LLCC as the two

  primary convective bands wrapped into the centre of the developing

  cyclone.  RSMC Nadi named the developing cyclone Yani at 22/0000 UTC

  while located approximately 230 nm SW of Honiara, Solomon Islands (or

  near 12.3S/162.5S), and noted that the cyclone was moving to the SE

  at 4 kts.

 

     Subsequent development was fairly rapid.  By 23/0600 UTC Yani had

  achieved hurricane intensity and reached its peak 12 hours later as a

  75-kt (max 10 min-avg) 960-hPa severe cyclone.  A ragged eye could be

  observed in both IR and visible satellite imagery at this time.  Peak

  intensity was maintained for 12 hours as the cyclone was steered very

  slowly in an anti-clockwise direction by a poleward-oriented mid to

  high-level ridge pushing from the east.  Soon afterwards an area of

  aggressive northeasterly wind shear overran Yani, tearing away its

  central convective core to the SE.  By 24/01500 UTC, Yani was

  downgraded from cyclone status near 13.1S/161.7E (or 245 nm SSE of

  Honiara, Solomon Islands) as the completely exposed LLCC made a sharp

  turn to the WNW in response to the strong subtropical ridge to its

  south.  The remnant LLCC eventually dissolved to the west of 160E in

  the Northern Coral Sea several days later.

 

  (Editor's Note: The peak 1-min avg MSW assigned by JTWC was 65 kts. 

  JTWC's peak T-number for Yani was T4.0, which was the lowest of all

  the warning agencies.  Brisbane and Fiji peaked at T5.0, while AFWA,

  SAB and Honolulu all reached T4.5 at some point.)

 

     There were no reports of any significant damage as a consequence

  of Tropical Cyclone Yani.

 

  (Report written by Simon Clarke)

 

 

 

                            TROPICAL DEPRESSION

                             (TD-05F / TC-04P)

                         29 November - 4 December

               --------------------------------------------

 

     Tropical Depression 05F, or TC-04P per JTWC's numbering, formed at

  the end of November deep in the tropics and moved rather uneventfully

  southward.  Fiji began mentioning the system, numbering it as Tropical

  Disturbance 05F, on 29 November when it was located about 400 nm north-

  northeast of Honiara, on Guadalcanal in the Solomon Islands.  The LOW

  lay beneath a 250-hPa ridge in an area of low shear and moderate

  diffluence.   At 1800 UTC RSMC Nadi classified the system as a tropical

  depression, relocating it somewhat south and west of its 0900 UTC

  position.  TD-05F continued to drift southward, but at 0400 UTC on the

  30th the center was once more relocated, this time back to the north.

  At this time gale warnings were initiated on the system in anticipation

  of its possibly increasing to gale force.

 

     JTWC issued a TCFA for the system at 30/0600 UTC.  Consolidating

  convection was wrapping into the LLCC which was located in a favorable

  region with good outflow and low to moderate vertical shear.   JTWC

  issued their first warning on TC-04P at 1200 UTC, placing the center

  about 265 nm east-northeast of Honiara, moving west-southwestward at

  4 kts.  The initial MSW was set at 35 kts (1-min avg), corresponding

  to Fiji's 10-min avg intensity of 30 kts.  These were the highest MSW

  values estimated by the two agencies during the system's short lifetime.

  By early on 1 December TD-05F/TC-04P was tracking south-southeastward

  toward a weakness in the subtropical ridge to its south.  As the system

  continued to track slowly in a southerly direction, it began to encounter

  increasing vertical shear.  By 0600 UTC on 2 December the LLCC had

  decoupled from the convection and JTWC issued their final warning,

  placing the center about 340 nm southeast of Honiara.  RSMC Nadi issued

  their final gale warning at 02/1800 UTC but continued to monitor the

  weakening depression for a couple of days.    TD-05F drifted back to the

  west and became quasi-stationary approximately 275 nm south-southeast of

  Honiara early on the 4th and was referenced for the last time in Fiji's

  Tropical Disturbance Summary issued at 04/2100 UTC.

 

     The line of demarcation between the warning AORs of Brisbane and Nadi

  (160E) runs right through the Solomon Islands with Honiara lying right

  on the line (-9.5S/160.0E).  Apparently because of this, the TCWC at

  Brisbane, Queensland, issued advisories for the Solomon Islands between

  0400 UTC on 30 November and 0600 UTC on 1 December.   JTWC, Nadi, SAB

  and Brisbane were all in agreement in their respective Dvorak ratings

  during the time of TD-05F's maximum intensity on 1 December, assigning

  estimates of T2.5/2.5.   However, AFWA and CPHC assigned a few ratings

  of T3.0/3.0 on 1 December.

 

     No reports of any damage or casualties resulting from this system

  have been received.

 

  (Report written by Gary Padgett)

 

  *************************************************************************

 

         SPECIAL FEATURE - SOURCES OF TROPICAL CYCLONE INFORMATION

 

     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:

 

     ftp://ftp.nhc.noaa.gov/pub/products/nhc/recon/

 

     Information regarding how to interpret the coded reconnaissance

  messages may be found at the following URL:

 

     http://www.nhc.noaa.gov/reconlist.shtml

 

  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:

 

     http://www.nhc.noaa.gov/archive/2004/index.shtml

 

  Links to tropical products archives for earlier years are available at

  the following URL:

 

     http://www.nhc.noaa.gov/pastall.shtml

 

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

 

     http://www.nrlmry.navy.mil/tc_pages/tc_home.html

 

  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:

 

     http://www.nrlmry.navy.mil/tc_pages/tc_home.html

 

     http://cimss.ssec.wisc.edu/tropic/tropic.html

 

  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.

 

     Additional tropical satellite imagery, along with looping ability for

  composite microwave imagery for the Western Hemisphere north of the

  equator, can be found at:

 

  (1) For the Eastern North Pacific:

 

     http://www.ssd.noaa.gov/PS/TROP/trop-epac.html

 

  (2) For the Atlantic, Gulf of Mexico and Caribbean Sea:

 

     http://www.ssd.noaa.gov/PS/TROP/trop-atl.html

 

     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):

 

    http://australiasevereweather.com/cyclones/

    http://www.typhoon2000.ph

    http://mpittweather.com

    ftp://ftp.aoml.noaa.gov/hrd/pub/landsea/padgett/

    http://www.tropicalcyclone2005.com/

 

 

     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:

 

    http://www.metoffice.gov.uk/weather/tropicalcyclone

   

 

                    TROPICAL CYCLONE REPORTS AVAILABLE

 

     JTWC now has available on its website the Annual Tropical Cyclone

  Report (ATCR) for 2005 (2004-2005 season for the Southern Hemisphere).

  ATCRs for earlier years are available also.

 

     The URL is:  https://metocph.nmci.navy.mil/jtwc.php

 

     Also, TPC/NHC has available on its webpage nice "technicolor"

  tracking charts for the 2006 Atlantic and Eastern North Pacific

  tropical cyclones; also, storm reports for all the 2006 Atlantic

  and Eastern North Pacific cyclones are now available, as well as

  track charts and reports on storms from earlier years.

 

     The URL is:  http://www.nhc.noaa.gov

 

 

     A special thanks to Michael Bath of McLeans Ridges, New South Wales,

  Australia, for assisting me with proofreading the summaries.

 

 

  PREPARED BY

 

  Gary Padgett

  E-mail:  garyp@alaweb.com

  Phone:  334-222-5327

 

  Kevin Boyle  (Northwest Pacific)

  E-mail:  newchapelobservatory@btinternet.com

 

  Simon Clarke  (Northeast Australia/Coral Sea, South Pacific)

  E-mail:  scla4255@bigpond.net.au

 

  *************************************************************************

  *************************************************************************

  Posted: 03.07.07 / Typhoon2000.ph, Typhoon2000.com