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Monthly Global Tropical Cyclone Summary November 1999
[Summaries and Track Data] [Prepared by Gary Padgett]

                  MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY

                              NOVEMBER, 1999

  (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.)

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

                           TROPICAL CYCLONE NAMES
                         for the SOUTH INDIAN OCEAN
                      and the SOUTHWEST PACIFIC OCEAN

     The Tropical Cyclone Warning Centre (TCWC) at Nadi, Fiji, has
  tropical cyclone warning responsibility for the South Pacific east of
  160E and from the equator to 25S.   The Meteorological Service of New
  Zealand at Wellington has warning responsibility for waters south of
  25S, but almost all tropical cyclones in this basin form north of 25S.
  When a rare cyclone forms in the Wellington area of responsibility
  (AOR), it usually will be assigned a name from the Fiji list (such as
  was done for Tropical Cyclone Gita last February).

     Tropical cyclone warning responsibility for South Indian waters west
  of 90E are shared by several TCWCs.       The Regional Specialty
  Meteorological Centre (RSMC) for the region is the office of Meteo
  France on the island of La Reunion.  However, following a long-standing
  practice, the sub-regional centres at Mauritius and Madagascar share
  the responsibility for actually naming tropical storms with Mauritius
  naming systems east of 55E and Madagascar covering the area west of
  55E.   RSMC La Reunion issues warnings for the basin independently of
  these sub-regional centres, but only advises regarding when or when not
  to assign a name to a developing cyclone.

     Names for the 1999-2000 season (** indicates name has already been
  assigned):

           South Indian                        Southwest Pacific
  -----------------------------------------------------------------------

     Astride **        Lisanne               Iris **       Trina
     Babiola **        Maizy                 Jo            Uka
     Connie            Nella                 Kim           Vicky
     Damienne          Ortensia              Leo           Walter
     Eline             Priscilla             Mona          Yolande
     Felicia           Rebecca               Neil          Zoe
     Gloria            Sophia                Oma           Ami
     Hudah             Terrence              Paula         Beni
     Innocente         Victorine             Rita          Cilla
     Jonna             Wilna                 Sam           Dovi
     Kenetha           Yanselma

  ***********************************************************************
                    
                            NOVEMBER HIGHLIGHTS

  --> Rare major November Caribbean hurricane almost becomes a
      Category 5 hurricane--moves eastward across much of Caribbean Sea
      and affects Lesser Antilles
  --> Other basins relatively quiet--a few Northwest Pacific storms

  ***********************************************************************
  
                           ACTIVITY BY BASINS

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

  Activity for November:  1 hurricane
                          2 possible subtropical storms

  NOTE:  Much of the information presented below was obtained from the
  TPC/NHC discussion bulletins issued with every regular advisory.  All
  references to sustained winds imply a 1-min averaging period unless
  otherwise noted.  A special thanks to John Wallace, a tropical cyclone
  enthusiast and college student from San Antonio, for providing me with
  a log which he had kept of all Atlantic/Northeast Pacific tropical
  waves that proved to be very valuable in helping to trace the pre-
  depression history of some of the cyclones.  


                       Atlantic Activity for November
                       ------------------------------

     The tendency toward increased late-season major hurricane activity
  seen in recent years in the Atlantic basin continued in 1999.   One of
  the strongest, if not the strongest, November hurricanes of the century
  developed south of Jamaica and took an unprecedented eastward track
  across the Caribbean Sea, ultimately affecting some of the Leeward
  Islands.   Hurricane Lenny reached an estimated MSW of 130 kts (which
  possibly will be increased to 135 kts in post-season analysis) when
  it was just south of the U. S. Virgin Islands.     The only other
  November hurricane in the official Atlantic historical database to
  have reached 130 kts was the destructive Jamaican hurricane of 1912.
  Fortunately, Lenny weakened somewhat before the inner core of the
  hurricane passed over some of the islands, so the effects were not
  nearly as devastating as they could have been.    Lenny is also the
  first hurricane on record to strike the Leewards moving in from the
  west.   The only other tropical storm to do so was Klaus in November,
  1984, which eventually became a hurricane to the north of the Antilles.


                        Non-tropical Gale Centers
                        -------------------------

     There were several gale centers in the subtropical Atlantic during
  the month which occasionally produced substantial amounts of
  convection.   At least two of these displayed enough organization in
  the convection to warrant their being mentioned in the Tropical Weather
  Outlooks (TWO) from TPC/NHC.   Neither system, however, evolved to the
  point that they could be considered tropical cyclones, but remained as
  hybrid (or possibly subtropical) storms.

     The first of these two more prominent LOWs formed a few hundred
  miles southeast of the Azores on 4 Nov.    It drifted slowly westward 
  through 6 Nov, then moved off to the northeast on the 7th as a trough
  approached.     The cyclone appeared to be best organized on 6 Nov as
  a band of convection wrapped around the center; however, there was no
  CDO and the center remained partially exposed at all times.  It was on
  the 6th that the LOW was mentioned in the TWOs as having some potential
  for tropical development.    Scatterometer passes on the 6th and 7th
  indicated surface winds on the order of 30-35 kts.   The system was 
  beneath a strong upper-level LOW throughout its lifetime; shear was
  quite low at peak intensity, but outflow was poor also.

     The second hybrid LOW was producing gales at least by 24 Nov (as
  per High Seas Forecasts from MPC), but it was on the 29th and 30th
  that convection began to appear more organized.  A TWO issued on the
  final day of the Atlantic Hurricane Season (30 Nov) indicated that if
  the trend seen during the morning continued, a tropical cyclone might
  possibly develop, but by 1 Dec the convection looked less impressive
  on satellite imagery.     This gale center meandered around in the
  mid-Atlantic roughly 1000 nm east and southeast of Bermuda for several
  days.  CIMSS low-level wind analyses indicated near-surface winds of
  35-40 kts, but these gale-force winds were sparse and were to be found
  exclusively in the northern semicircle--likely a result of the steep
  pressure gradient between the LOW and a ridge to the north.

     A special thanks is due John Wallace, a student at the San Antonio
  branch of the University of Texas and a rather knowledgeable tropical
  cyclone enthusiast, for supplying me with much of the above information
  on the hybrid systems.    John also sent me some tracking information
  for the two LOWs which I used to construct tracks for these systems in
  the accompanying cyclone tracks file.


                        Hurricane Lenny  (TC #16)
                             13 - 21 November
                        -------------------------

     An broad, weak area of low pressure accompanied by thunderstorms
  appeared in the extreme southwestern Caribbean Sea early on 8 Nov.
  Over the next few days this system drifted slowly northwestward toward
  the region generally between Jamaica and Central America.    The
  convection was very slow to organize, although upper-level winds were
  generally favorable for tropical development.   By the 13th the LOW
  had become better organized, and a reconnaissance plane from the
  53rd Weather Reconnaissance Squadron of the U. S. Air Force Reserves
  investigated the disturbance and found it to be sufficiently organized
  enough so that TPC/NHC upgraded it to a tropical depression and began
  issuing advisories.   The depression at this time was centered about
  300 nm west-southwest of Kingston, Jamaica.

     By early the next morning the LLCC had become better involved with
  the deep convection although the coldest cloud tops (to -80 C) remained
  north of the center.    Two ship observations from near the center
  indicated winds of only around 12-13 kts, so the system was kept as
  a tropical depression in the 14/0900 UTC advisory.   By mid-morning
  satellite estimates were at tropical storm intensity, but there had
  been no recent ship or island observations to confirm that, so the
  depression was not upgraded at this time--likely due to the earlier
  ship reports of light winds.  However, at one point during the early
  morning, a feature which looked like a developing eye was briefly
  visible.     A midday flight by the Hurricane Hunters found FLW of
  66 kts at 300 m just southeast of the center with a CP of 992 mb,
  so the depression was upgraded to Tropical Storm Lenny in a special
  advisory at 1915 UTC.   Lenny's initial MSW was set at 55 kts and
  the new storm was centered approximately 175 nm southwest of Kingston,
  Jamaica.

     In the 2100 UTC advisory the MSW was increased to 60 kts with the
  CP having fallen further to 988 mb, and Lenny was upgraded to a
  hurricane with 70-kt winds--the season's eighth--in a special Tropical
  Cyclone Update issued at 2150 UTC.   During the evening an SSM/I pass
  revealed an eye 15-20 nm in diameter which had been obscured by a
  burst of convection.     The Discussion Bulletin accompanying the
  15/0300 UTC advisory contained the following remark: "Obviously, the
  rapid intensification of this tropical cyclone was not anticipated.
  This again underscores our limited ability to predict intensity
  changes."  (Authored by Dr. Richard Pasch.)  The rapid intensification
  of Lenny from a tropical depression to a hurricane was not the only
  unexpected thing which happened with this cyclone.   During the night
  the pressure continued to fall to 971 mb, and a reconnaissance plane
  found 100-kt winds at 850 mb.  The surface MSW was increased to 85 kts
  at 15/0900 UTC as Lenny moved slowly east-southeastward south of
  Jamaica.  The wind radii were fairly small:  hurricane-force winds
  extended outward from the eye only 20 nm, and gale-force winds reached
  out 75 nm to the northwest and 40 nm to the northeast.

     During the morning the rapid intensification trend was halted and
  Lenny weakened significantly.  The highest winds found by the Hurricane
  Hunters on a midday flight were 73 kts measured by a GPS dropwindsonde
  in the southwest quadrant.     The pressure had risen to 981 mb and
  subsequently rose to 984 mb during the afternoon.  The MSW was lowered
  to 70 kts at 16/0300 UTC.   There was no eye evident in either micro-
  wave or infrared imagery, and the cloud pattern, while containing much
  very deep convection, was not all that well organized.   The reason for
  this weakening was not understood very well either--possibly it was
  due to the fact that the very small inner core region was affected by
  some subtle environmental changes.   However, during the night the
  weakening trend was reversed and Lenny began to rapidly strengthen
  again.  An early morning (16th) reconnaissance flight found that the
  pressure had dropped once more to 971 mb and the maximum FLW found at
  850 mb was 109 kts.   The plane also reported a 45-nm diameter eye.
  Cloud tops near the center were -80 to -85 C and some satellite
  intensity estimates were up to 102 kts (T5.5).  The MSW was upped once
  more to 85 kts based on this information, and this was possibly
  conservative.

     Hurricane Lenny was steered on an unprecedented easterly course
  across the central Caribbean Sea by the flow around the southern end
  of a deep-layer trough to the north.    The CP had fallen to 965 mb by
  around midday on 16 Nov, and a GPS dropwindsonde measured mean boundary
  layer winds of 107 kts and 96 kts at the surface.   By 1800 UTC Lenny
  had become the season's fifth major hurricane on the Saffir/Simpson
  scale with 100-kt MSW at a point about 200 nm south-southeast of Santo
  Domingo.    Early in the evening a center fix by a new WC-130 Model J
  Hurricane Hunter aircraft found a CP of 958 mb, and a GPS dropwindsonde
  measured winds of 126 kts at 907 mb in the southeast eyewall.  The San
  Juan WSR-88D radar revealed a 25-nm diameter eye surrounded by a
  closed wall.  The storm had grown larger in areal extent with gales
  extending outward 175 nm and hurricane-force winds reaching outward
  60 nm from the center.

     Early on the 17th another GPS dropwindsonde measured 132 kts at
  924 mb and 110 kts just above the surface.     In an Intermediate
  Advisory issued at 1300 UTC, Lenny's MSW was increased to 115 kts,
  thereby making the storm the fifth Category 4 hurricane of the year.
  The 17/1500 UTC advisory stated that a gust to hurricane force had
  already been observed on St. Croix.   A morning reconnaissance flight
  found an extrapolated surface pressure of 942 mb and 134-kt winds at
  700 mb, and a GPS dropwindsonde measured mean boundary layer winds of
  118 kts.   By 1800 UTC dangerous Hurricane Lenny had become a very
  strong Category 4 hurricane with the MSW estimated at 130 kts and
  the CP measured at 934 mb.  The maximum FLW had increased to 149 kts,
  the mean boundary layer winds measured by a GPS dropwindsonde were
  155 kts, and peak winds at the 891-mb level had reached 180 kts a 
  couple of hours earlier.

     Lenny began to move more toward the northeast early on 17 Nov and
  was centered only about 20 nm south of the western part of the island
  of St. Croix at 1800 UTC when its winds reached 130 kts.  St. Croix
  reported sustained winds of 72 kts with gusts to 97 kts during the
  afternoon, and St. John reported gusts to 75 kts.   Lenny's forward
  motion slowed considerably as it approached the Leeward Islands.
  The storm's center moved east-northeastward to near St. Maarten and
  Anguilla by 19/0000 UTC and moved slowly over those islands, then
  turned gradually toward the east-southeast, passing near St. Barthlemy
  and later over Antigua around 0000 UTC on 20 Nov.   After peaking in
  intensity Lenny began to slowly weaken, likely due to upwelling since 
  initially the atmospheric environment was not particularly hostile.
    
     At 18/0000 UTC the CP had risen to 939 mb and the MSW was lowered
  slightly to 125 kts based on the most recent reconnaissance FLW of
  128 kts.   By 0600 UTC the CP had continued to rise to 947 mb, but
  an aircraft encountered 700-mb winds of 145 kts and an eyewall GPS
  dropwindsonde indicated winds of 132 kts near the surface.  However, 
  by the time the storm had reached St. Maarten a reconnaissance flight
  found FLW of only 107 kts, so the MSW was decreased to 95 kts with
  the CP having risen to 975 mb.     Lenny had been downgraded to a
  60-kt tropical storm by the time it reached Antigua early on 20 Nov.
  Some shearing of the system at the cirrus level was becoming apparent
  in satellite imagery.

     After passing through the Leewards the weakening Lenny moved slowly
  east-southeastward away from the islands.  The large, diffuse center
  passed about 100 nm east of Guadeloupe around 1200 UTC on 20 Nov and
  had reached a point about 125 nm east of the island of Dominica by
  21/0000 UTC.    Lenny was downgraded to a depression at 0900 UTC since
  there had not been any surface reports of tropical storm-force winds
  for 21 hours and there were neither scatterometer nor low-cloud winds
  at this threshold.   However, the long anticipated movement to the
  northeast began as the once powerful hurricane was downgraded to a
  dissipating depression.   The weakening center had moved northeast-
  ward to a point about 375 nm east of St. Maarten when the final
  advisory was issued at 1800 UTC on 21 Nov.

    There were quite a few observations of winds well above hurricane
  force from the islands during Lenny's passage.   A gust to 85 kts
  was reported on Virgin Gorda in the British Virgin Islands during the
  evening hours of 17 Nov.  Later that evening a gust to 88 kts was
  observed on the small island of Saba.    Around midday on the 18th
  St. Maarten reported wind gusts to 94 kts while St. Barthelemy reported
  gusts to 108 kts.    During the evening hours of 18 Nov a portion of
  the eye was over St. Maarten and a ship (CAIT NAMARO) in Simpsons Bay
  experienced winds of 87 kts.   Shortly after midnight on the 19th,
  St. Maarten was still reporting sustained winds of 64 kts gusting to
  90 kts.
  
     Damage was widespread and rather severe on some islands, but in
  general was much less than it could have been had the intense inner
  core of Hurricane Lenny passed directly over some of the islands when
  the storm was near its peak intensity.      The latest information 
  available to the author indicates that there were a total of 12 deaths
  attributed to Hurricane Lenny with four of these on Guadeloupe.  And
  while several hundred homes were destroyed, the majority of damage
  appears to have been to the infrastructure and environment, especially
  coastal roads, sea defenses, piers, and beaches.   The western coasts
  of the islands were the most severely affected, as would be expected
  with the hurricane approaching from the west.   Industries affected
  most severely were agriculture, fishing, and tourism.  One preliminary
  estimate placed the total damage amount at several hundred million
  U. S. dollars.

     On Antigua there was severe beach erosion with many roads washed
  out and some mud slides resulting from the heavy rainfall.  The nearby
  island of Barbuda was especially hard hit by the torrential rains.
  Almost 65% of the island was under water, roads were severely damaged,
  and the ground water supply was contaminated.    About 95% of the
  agriculture industry, which includes peanuts, vegetables, corn, and
  coconuts, was destroyed.     St. Kitts suffered severe damage from
  flooding and wave action with the total damage estimated to be near
  $41 million in U. S. dollars.   About $50 million (USD) in damage
  was sustained by hotels on the island of Anguilla.  Even Dominica,
  which lay well south of the track of Lenny's eye, was affected
  rather extensively by the storm.   Hotels along the island's west
  coast suffered major damage, about 35% of the banana crop was wiped
  out, about 40% of coastal roads were washed out, and many piers and
  port facilities were damaged.

     More information about the effects of Hurricane Lenny may be found
  at the following website:  http://wwwnotes.reliefweb.int>.  Click on
  the "Natural Disasters" link.  

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

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

  Activity for November:  No tropical cyclones

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

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

  Activity for November:  2 tropical depressions (a)
                          3 tropical storms (b)
                          1 typhoon (c)

  (a) One of these was not carried operationally as a tropical
      depression, but later evolved into a vigorous subtropical
      storm.

  (b) Only one of these was carried operationally as a tropical
      storm.      One storm evolved out of a Hawaiian Kona storm
      (subtropical) and the other was a monsoon depression carrying
      gale-force winds.  Additionally, Tropical Storm Frankie/Sendang
      was not treated as a tropical storm by JMA.

  (c) Not treated as a typhoon by JMA.

  NOTE: Most of the information on each cyclone's history presented in 
  the narrative will be based upon JTWC's advisories, and references to
  winds should be understood as a 1-min avg MSW unless otherwise noted.
  However, in the accompanying tracking document I have made comparisons
  of coordinates with JMA (Japan) and the Philippines (PAGASA) when their
  positions differed from JTWC's by usually 40-50 nm or more.  Also, as
  announced earlier in a separate posting, a column of 10-min avg MSW
  is included--the values being obtained from either PAGASA's or JMA's
  advisories.  A special thanks to Michael V. Padua, owner of the
  Typhoon '99 webpage, for sending me the PAGASA and JMA tracks.

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


                  Northwest Pacific Activity for November
                  ---------------------------------------

     Sporadic activity continued over the Northwest Pacific basin during
  November, but there were no intense typhoons.    Only one storm was
  classified as a typhoon and this by JTWC only.    One weak minimal
  tropical storm affected the central Philippines--this was treated as
  a tropical storm by JTWC and PAGASA but not by JMA.   One additional
  short-lived system was carried operationally as a tropical depression
  by JTWC and JMA, but there were drastic differences between the two
  TCWCs during the latter portion of the system's life.

     A circulation developed on 5 Nov northeast of the Mariana Islands
  along the tail end of a shear line.   JMA first mentioned the system
  in their High Seas Warnings at 0600 UTC, placing the center about
  400 nm northeast of Guam, but subsequently relocated the center to the
  south and west six hours later.   JTWC initiated warnings on TD-28W
  at 1800 UTC with the center estimated to be just east of the northern
  Marianas and accompanied by a broad and very disorganized area of
  convection.  Satellite intensity estimates were 25 kts but ship and
  scatterometer data indicated winds to 30 kts.  The depression had good
  outflow aloft but was located in an environment of moderate vertical
  shear.   The depression moved little during the time that it was in
  warning status by JTWC.    At 06/0600 UTC it was relocated to just
  west of the northern Marianas, but at 1200 UTC the LLCC had become
  difficult to locate and shear was increasing, so the final warning
  was issued with the dissipating center about 200 nm north of Guam.

     While earlier during the depression's history, JTWC's and JMA's
  position estimates had been in reasonably close agreement for such a
  weak, disorganized system, at 06/1200 UTC JMA gave a center position
  almost 450 nm to the northeast of JTWC's final warning position.
  JMA subsequently tracked this center fairly quickly northward and
  northeastward into the subtropics.      The final JMA bulletin, at
  07/1800 UTC, placed the center more than 1000 nm northeast of Guam.
  I really don't have enough information to piece together just what
  took place; i.e., whether or not JMA picked up on a totally different
  LLCC or else this was a redevelopment of the center within the same
  general circulation.  Unfortunately, I don't have any JMA information
  available for 0600 UTC on 6 Nov, and since JMA doesn't assign any
  numbers or other identification to tropical depressions, I have no
  idea if that TCWC considered the LLCC tracked on 6 and 7 Nov to be
  a continuation of the center being following on 5 Nov or a totally
  different system.

     There were three interesting systems in the Northwest Pacific in
  November for which warnings were not issued by any TCWC that I'm aware
  of.    I am indebted to Dr. Mark Lander of the University of Guam for 
  providing me with much information and some satellite imagery of these 
  systems.    Dr. Lander is a professor at the Water and Environmental
  Research Institute of the Pacific at the University of Guam, and for
  ten years worked under a grant from the Office of Naval Research to
  conduct research on tropical cyclones.      Dr. Lander worked closely
  during those years with forecasters and satellite analysts at JTWC.
  A very special thanks to Mark for providing me with information on
  these weather systems.

     In keeping with the practice I initiated back during August, I have
  chosen to designate these systems with letters of the Greek alphabet.
  (See the Global Tropical Cyclone Summary for August, 1999, for a
  discussion of this subject.)   "Zeta" was a large monsoon depression
  with peripheral gale-force winds which moved into southern Vietnam and
  was responsible for very disastrous flooding which claimed hundreds of
  lives.  "Eta" began as a small tropical depression deep in the tropics
  near Pohnpei and never attained tropical storm intensity, but later
  merged with a frontal shear line and deepened into a large, intense
  subtropical-type cyclone of near typhoon strength.   Finally, "Theta"
  was a large Hawaiian-style Kona storm which evolved into a small,
  sheared tropical cyclone which likely was briefly of tropical storm
  intensity.   The narrative below on these three weather systems is
  pretty much just as I received it from Mark with a slight amount of
  editing performed and a few geographical references added.


                   Tropical (Monsoon) Depression "Zeta"
                              2 - 5 November
                   ------------------------------------

     During the period 3-5 Nov, a monsoon depression consolidated in
  the South China Sea and moved westward into Vietnam on 5 Nov.  Gale-
  force winds were occurring in the primary cloud band to the north and
  east of the LLCC, and were probably nearing gale force in the core as
  "Zeta" made landfall.

      This tropical cyclone was a typical monsoon depression with (among
  other things):
     (1) a large, sprawling tropical LOW with mesoscale convective
         systems loosely organized into large-scale bands
     (2) a large area of outflow cirrus and cirrus debris organized into
         a well-defined, nearly symmetrical, anticyclonic pattern
     (3) a wind distribution featuring a core of lighter winds of
         15-20 kts, with near gale and gale-force winds displaced
         100-250 nm outside of the low-level wind center (often in
         a backwards "C"-shaped pattern)

     Monsoon depressions become conventional tropical cyclones when they
  acquire a persistent core of deep convection associated with higher 
  core wind speeds.  About two-thirds of Northwest Pacific basin tropical
  cyclones begin as monsoon depressions.  JTWC (and likely other TCWCs
  as well) has for years had trouble with monsoon depressions.  Dvorak 
  satellite analysis (which was primarily developed in the Atlantic
  basin where monsoon depressions are extremely rare) does not address
  them as applied, and the higher winds are located at some distance
  away from the core.   JTWC prefers to attribute the gales in these
  systems to "monsoon surges" or other types of "gradient" winds.  The
  danger is that when they acquire persistent central convection, an
  "instant" (i.e., Warning #1) tropical storm is born with a very large
  radius of gales.

     In any case the monsoon depression that moved into Vietnam on 5 Nov
  was a "significant" tropical cyclone with deadly impact.  According to
  a story from the 12 Nov edition of the_Pacific Daily News_ (of Guam),
  the depression dumped more than 7 feet (2100 mm) of rain on seven
  central provinces during a three-day period.   At least 574 people
  were known dead after Vietnam's worst flooding in a century.   A
  preliminary estimate places the damage at $215 million.

     Another report received by the author dated 15 Nov gives some
  additional information on the aftermath of the flooding:  thousands
  of cases of various diseases; 622 deaths; 70 persons missing; over
  41,000 homes destroyed; 870,000 homes damaged; 94,000 classrooms
  destroyed; almost 100,000 hectares of rice fields and other farmland
  inundated; 205,000 metric tons of food lost; over 3000 hectares of
  shrimp and fish farms destroyed; 1,470 bridges destroyed; and 25,000
  head of cattle killed.


                  Tropical Storm Frankie/Sendang  (TC-29W)
                              6 - 10 November
                  ----------------------------------------

     A Significant Tropical Weather Outlook (STWO) from JTWC on 3 Nov
  indicated that an area of convection had developed and persisted for
  about 12 hours several hundred miles south of Guam.  Animated visible
  satellite imagery indicated that a broad LLCC might be forming.  By
  4 Nov the system had become better organized with a LLCC evident,
  falling surface pressures, and equatorial westerlies to the south
  feeding into the disturbance.  The development potential was upgraded
  to Fair but was downgraded to Poor the following day when the LLCC was
  no longer apparent in satellite imagery.     The weakening trend,
  however, reversed itself and the disturbance once more began to exhibit
  increased organization.     A Formation Alert was issued by JTWC at
  05/0600 UTC, upgrading the development potential to Good.  Convection
  remained embedded in a very active monsoon trough, but there was once
  more evidence of a LLCC associated with the convection while vertical
  shear was weak to moderate.

     JTWC upgraded the system to TD-29W at 0600 UTC on 6 Nov when it was
  centered about 200 nm north of Koror or over 500 nm east of southern
  Samar in the Philippines.   Outflow was good and the convection was
  slowly increasing in organization in a moderate shearing environment.
  The depression was located under the weak steering influence of a
  subtropical ridge to the northeast.   Intensification proceeded at a
  slow rate due to the persistent easterly shear.  A subtropical ridge
  to the northwest became the dominant steering influence and caused
  the depression to track toward the west-southwest.  PAGASA commenced
  issuing warnings at 06/1800 UTC, naming the depression Sendang.

     By 07/1800 UTC, after having moved west-southwestward for about
  24 hours, Sendang turned back to the west-northwest and began to
  show increased convective organization.   At 0000 UTC on 8 Nov the
  depression was centered northeast of the Leyte Gulf and moving west-
  northwestward at 18 kts.   PAGASA upgraded Sendang to a 40-kt tropical
  storm at this time while JTWC waited until 0600 UTC before classifying
  the system as Tropical Storm Frankie.   Frankie was then located over
  northern Samar.    Satellite intensity estimates were 30-35 kts, but
  a scatterometer pass showed winds of 35 kts.   By 1200 UTC the storm's
  convection was decreasing due to land interaction, and at 1800 UTC
  JTWC downgraded Frankie back to a tropical depression.   PAGASA,
  however, kept Frankie/Sendang at tropical storm levels for six more
  hours.   The center of the storm at this time was in the Sibuyan Sea
  about 65 nm east of Mindoro (this based upon JTWC information). Some
  deep convection had begun to regenerate southeast and northwest of the
  LLCC.

     By 09/0000 UTC Frankie/Sendang had become quasi-stationary in the
  vicinity of Masbate island with a fully exposed LLCC located about
  40 nm east of the deeper convection.   PAGASA had downgraded Sendang
  to a depression by this time, and the weakening system spent the next
  day or so meandering about the central Philippines in the general
  area of Masbate, Sibuyan, and extreme southeastern Luzon.   Some
  orographically-induced convection occasionally was seen, but the
  weakening trend continued and JTWC issued the final warning at 0000 UTC
  on 10 Nov.   No reports of damage or casualties have been located by
  the author, although one press report mentioned that some Filipino
  rice paddies had been flooded due to the storm's rains.  (It should be
  noted that JMA never upgraded Frankie/Sendang to a tropical storm in
  their bulletins.)


                Tropical Depression/Subtropical Cyclone "Eta"
                              8 - 16 November
                ---------------------------------------------
                                                             
     During the first week of November, the monsoon trough extended
  eastward into the eastern Caroline Islands--a rare event this time of
  year.   During this active period of the monsoon, an unnumbered/unnamed
  monsoon depression formed in the South China Sea, TD-28W formed north-
  northeast of Guam, Tropical Storm Frankie (TC-29W) formed near the 
  Philippines, Typhoon Gloria (TC-30W) formed northwest of Guam, and a 
  small unnumbered/unnamed tropical cyclone formed northeast of Pohnpei.

    The tropical disturbance that became Tropical Cyclone "Eta" formed
  near Pohnpei at the eastern end of the monsoon trough.    A prominent
  TUTT cell--with its own areas of deep convection--was present to the
  northeast of this disturbance.   Around 8 Nov, well-defined low-level
  cloud lines indicated that a tropical depression had formed in
  association with the persistent deep convection near Pohnpei.  The
  depression was centered about 200 nm north-northeast of Pohnpei at
  08/0000 UTC.  This tropical depression moved to the northwest into a 
  relatively cloud-free environment.      It was a very small tropical 
  cyclone with a shear pattern structure.  The deep convection near the
  small LLCC collapsed and redeveloped several times.    This sort of
  behavior of the deep convection associated with a weak sheared tropical
  cyclone is commonly indicative of an intensity of about 30 kts, as
  confirmed by an ERS-2 Scatterometer pass at 1215 UTC on 9 Nov which 
  showed a small region with winds of at least 25 kts.
  
    The tropical cyclone recurved as it approached a shear line, reaching
  the westernmost point of its track at 1200 UTC on 10 Nov when it was
  centered about 800 nm northwest of Pohnpei or 600 nm northeast of Guam.
  On 11 Nov the tropical cyclone merged with the the shear line cloud 
  band and then began to re-intensify, becoming a subtropical storm with
  35-kt winds at 12/1200 UTC when it was located 550 nm north of Wake
  Island.  The system evolved into a large and intense subtropical
  cyclone and peaked at near typhoon intensity on 15 Nov when it was
  centered roughly 500 nm northwest of Midway.   The intense subtropical 
  LOW moved eastward and weakened on 16 Nov about 475 nm north-northeast
  of Midway.

                 Typhoon Gloria/Trining  (TC-30W / STS 9922)
                               13 - 16 November
                 -------------------------------------------

     The final named tropical cyclone of 1999 in the Northwest Pacific
  basin had its beginnings in an area of convection which had developed
  by 10 Nov over the Philippine Sea along the tail end of a shear line.
  By the next day the area had moved westward and was located east of
  northern Samar.   No LLCC was apparent yet but atmospheric conditions
  in general were considered quite favorable for development, so the
  system was given a Fair development potential by JTWC.    The daily
  STWO issued at 0600 UTC on 12 Nov indicated that the main area of
  interest had drifted southward and was located about 330 nm east of
  Samar.  A Formation Alert was issued at 0700 UTC and indicated that
  animated visible imagery showed convection building around a LLCC.
  The system had some monsoon depression characteristics at the time
  with the strongest winds around the periphery.   A second Formation
  Alert was issued at 13/0500 UTC, locating the center of the developing
  depression about 150 nm to the north of its position the previous day.

     JTWC upgraded the disturbance to a tropical depression at 0600 UTC
  on 13 Nov with the center roughly 400 nm east of Catanduanes Island in
  the Philippines.    PAGASA initiated warnings at 1800 UTC, naming the
  depression Trining.   The depression was steered slowly northward by
  a subtropical ridge to the northeast.    Trining's development was
  initially hampered by easterly shear resulting from converging
  monsoonal flow and easterlies situated to the northeast.   Early on
  14 Nov the LLCC reconsolidated to the west beneath resurging deep
  convection while the old center weakened.   At 0600 UTC JTWC relocated
  the center to the west-northwest and upgraded the depression to
  Tropical Storm Gloria--the center was located about 475 nm east of
  Cabo Engano on the northeastern tip of Luzon at the time.  By 1800 UTC
  the MSW had increased to 45 kts as Gloria moved northward at 10 kts
  from a position about 350 nm southeast of Okinawa.

     As the 15th began drier air and increasing vertical shear had
  led to the dissipation of most of the convection in the southern half
  of the circulation.     JTWC maintained the MSW at 45 kts through
  0600 UTC and then decreased it to 40 kts at 1200 UTC, but JMA raised
  their 10-min avg MSW estimate to 50 kts at 0600 UTC.    By 1800 UTC
  Gloria had accelerated and was moving northeastward at 36 kts.  This
  rapid motion with the flow decreased the relative shear and allowed 
  the cyclone to strengthen.    In an infrared image sent to me by Mark 
  Lander, taken at 15/1130 UTC, an eye appears to be forming; and in
  another image taken two hours later, a cloud-filled eye is clearly
  visible.  After having reduced the MSW to 40 kts at 1200 UTC, JTWC
  abruptly increased the MSW to 65 kts at 1800 UTC.  The 20-nm diameter
  eye was centered about 525 nm east of Okinawa at this time.

     Gloria's tenure as a typhoon was short-lived as drier air continued
  to invade the circulation.   The storm passed about 300 nm north of
  Iwo Jima at 16/0000 UTC, racing northeastward at 40 kts.   Convection
  had decreased and the eye was no longer apparent.   Gloria was being
  steered by the combination of a mid-latitude trough over Japan and
  a subtropical ridge located to the southeast of the typhoon.   By
  0600 UTC Gloria was weakening and had become primarily extratropical,
  so JTWC issued their final warning on the storm, which was located
  about 350 nm east-southeast of Tokyo and moving northeastward at
  47 kts.  Based on satellite estimates the final MSW was reported as
  55 kts.  JMA issued one additional warning on the system at 1200 UTC
  with the storm having moved quickly northeastward to a point almost
  650 nm east of Tokyo.


                 Subtropical Storm/Tropical Cyclone "Theta"
                         26 November - 1 December
                 ------------------------------------------ 
                 
     On 26 Nov a large Kona LOW (or Kona storm) formed to the west-
  northwest of Hawaii or about 120 nm south of Midway.  The Kona LOW is
  a Hawaiian regional designation for cut-off LOWs in the subtropics 
  that turn the winds in Hawaii from trades to southwesterly, or Kona 
  (leeward-side) winds.   This large Kona LOW drifted to the southwest, 
  crossing the International Dateline on 27 Nov at a point about 250 nm
  southwest of Midway.      The system intensified and acquired the
  characteristics of a subtropical cyclone.   The core convection of the
  LOW began to detach from the large outer spiral cloud band as it 
  slowly evolved from its subtropical structure to that of a tropical
  cyclone.   On the morning of 29 Nov, a small area of persistent deep 
  convection consolidated near the core to become a midget tropical
  cyclone.

     The system by now was located more than 400 nm west-southwest of
  Midway.     The very small tropical cyclone drifted to the west and  
  slowly weakened as shear caused the LLCC to become partially exposed 
  on the north side of the deep convection.    The estimated MSW had
  dropped to 30 kts by 0000 UTC on 30 Nov--at this point the center
  was about 400 nm north-northeast of Wake Island.  The shear continued
  as the deep convection was first pushed off to the south side of the 
  circulation and later collapsed to leave a swirl of low cloud lines.
  The final position given in the track file places the dissipating
  center about 425 nm northwest of Wake Island at 0000 UTC on 1 Dec.

     Based upon the best track data supplied by Mark, the system's peak
  intensity as a subtropical storm was 50 kts from 0600 to 1200 UTC
  on 27 Nov.     After "Theta" had made the transition to a tropical
  cyclone, the peak MSW had dropped to 40-45 kts.
                   
  ***********************************************************************

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

  Activity for November: No tropical cyclones

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

  SOUTH INDIAN OCEAN (SIO) - South Indian Ocean West of Longitude 90E

  Activity for November:  No tropical cyclones

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

  AUSTRALIAN REGION (AUG) - From Longitude 90E Eastward to Longitude 160E

  Activity for November:  No tropical cyclones

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

  SOUTHWEST PACIFIC (SWP) - South Pacific Ocean East of Longitude 160E

  Activity for November: 1 tropical depression (possibly hybrid)
                         1 depression (or LOW)--likely baroclinic


                  Southwest Pacific Activity for November
                  ---------------------------------------

     While there were no named tropical cyclones in the Southwest Pacific
  basin during November, there were a couple of systems for which gale
  warnings were issued.  The first depression was analyzed about 400 nm
  southwest of Fiji at 1200 UTC on 1 Nov.   All the convection and the
  peripheral gales were confined to the southern semicircle.  The system
  drifted slowly southward and into Wellington's AOR on 2 Nov.  Someone
  (Patrick Hoareau I think) sent me a visible satellite image taken at
  05/0031 UTC which showed a tightly-wound vortex of low- and mid-
  level clouds right along the 165th meridian between New Zealand and
  Australia.   I wrote to Steve Ready of the New Zealand Meteorological
  Service to see if there were any connection with the tropical
  depression of a few days earlier.  So Steve sent me a brief history
  of this system, most of which is included in the following paragraphs:

     "At 0000 UTC on 3 Nov the depression was centered near 29.0 S,
  172.0 E with a CP of 1001 mb.  At this stage the LLCC was located near
  the northern edge of a dense overcast.   Between 0800 and 1700 UTC on
  the 3rd, the LOW wound up very quickly with a dry slot working its way
  around a blob of central convection to the northern side of the LLCC.
  As far as we could ascertain, the CP fell to 994 mb.  The LOW deepened
  in response to a shortwave trough shifting across the northern Tasman
  Sea and tilting over to become negatively oriented (i.e., northeast-
  southwest).  The behaviour of this shortwave trough increased the
  divergence in the vicinity of the LLCC, causing it to transform into
  a more significant LOW system.  The tropical depression brought a pool
  of moisture and vorticity into the subtropics which was right for being
  picked up by an appropriate upstream shortwave trough.

     This type of development is quite common in this part of the world.
  The tropical input did play a very important part, but you would have
  to call it a hybrid LOW as the mid-latitude forcing was also essential
  to its development.  The LOW continued to track south-southwestward at
  3 to 6 degrees (of latitude) per day and on the 5th and 6th a lot of
  the clouds around the centre evaporated with a wee bit of convective
  activity left in the southeast quadrant.     The remains of the LOW
  passed close to the southwest corner of the South Island before being
  absorbed into the high-latitude westerlies south of 50S between 170E
  and 180.   On 5 Nov the CP rose from near 990 mb to just over 1000 mb."
  (A special thanks for Steve for sending me a write-up of this
  interesting system.)

     There was another LOW pressure system in the South Pacific which
  produced gales around mid-month, but this was never referred to in
  warnings from Nadi as a "tropical" depression, so likely it was more
  baroclinic in nature.  The LOW was located about 150 nm south-southeast
  of Tahiti at 0000 UTC on 13 Nov and tracked generally to the south-
  southwest over the next 36 hours, being located about 525 nm south-
  southwest of Tahiti at 14/1200 UTC.  A couple of tropical disturbances
  which formed west of the Dateline during the latter part of November
  were designated as 01F and 02F by the Nadi TCWC, but neither attained
  sufficient enough organization to be classed as a tropical depression.

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

                              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 included in the July, 1998 summary.
  I will include this glossary from time to time, primarily in "lean"
  months without a lot of tropical cyclone activity to cover.  But if
  anyone missed receiving it and wishes to obtain a copy, send me an
  e-mail privately and I'll forward them a copy.

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

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

    The track files are not being sent via e-mail.  They can be retrieved
  in the following manner:

       (a) FTP to:  hrd-type42.nhc.noaa.gov [140.90.176.206]
       (b) Login as: anonymous
       (c) For a password use your e-mail address
       (d) Go to "data" subdirectory (Type: cd data)
       (e) Set file type to ASCII (Type: ascii)
       (f) Transfer file (Type: get remote_file_name local_file_name )
           (The files will be named with an obvious nomenclature--using
           November as an example:   nov99.tracks)
       (g) To exit FTP, type: quit

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

     The first summary in this series covered the month of October,
  1997.   If anyone wishes to retrieve any of the previous summaries,
  they may be downloaded from the aforementioned FTP site at HRD.  The
  summary files are catalogued with the nomenclature:  nov99.sum, for
  example.

    Back issues can also be obtained from the following websites
  (courtesy of Michael Bath, Michael V. Padua, Tom Berg, Michael
  Pitt, and Rich Henning):

    http://australiansevereweather.com/cyclones/>
    http://www.geocities.com/capecanaveral/6825>
    http://www.hcane.com/tropcl.html>
    http://www.qisfl.net/home/hurricanemike>
    http://www.met.fsu.edu/gsc/Docs/Grads/henning/cyclones/>

     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.met-office.gov.uk/sec2/sec2cyclone/sec2cyclone.html>


                   TROPICAL CYCLONE REPORTS AVAILABLE

     JTWC now has available on its new website the completed Annual
  Tropical Cyclone Report for 1998.  Also, reports for each year from
  1959 through 1997 are available in Adobe Acrobat format.

     The URL is:  http://199.10.200.33/jtwc.html>

     TPC/NHC has available on its webpage nice "technicolor" tracking
  charts for the 1998 Atlantic and Eastern North Pacific tropical
  cyclones, and preliminary storm reports for all the 1998 Atlantic
  and Eastern North Pacific cyclones are now available.  Also, a few
  preliminary reports for some of the 1999 tropical cyclones are
  already available.

     The URL is:  http://www.nhc.noaa.gov/1998.html>

  Prepared by: Gary Padgett
  E-mail:  garyp@alaweb.com
  Phone:  334-222-5327 (nights & weekends) / 850-882-2594 (weekdays)

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

Document: summ9911.htm
Updated: 4th January 2007

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