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


                                JULY, 2004

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


                             JULY HIGHLIGHTS

  --> Northwest Pacific rather quiet while Northeast Pacific heats up


                 ***** Feature of the Month for July *****


     During the summer (boreal) of 2003, I sent another one of my famous
  surveys to the members of an informal tropical cyclone discussion group
  of which I am a member.   I also recently sent it to a few other persons
  in the tropical cyclone community.   I intend to present the results of
  the survey as monthly features spread over several months, beginning with
  the May, 2004, summary.   The survey consisted of ten multiple-choice
  questions dealing with various tropical or subtropical cyclone-related
  issues, and two or three questions will be considered each month.

     The persons responding to the survey are listed below.  A special
  thanks to each for taking the time to respond to the questions.

  Michael Bath - New South Wales, Australia
  Bruno Benjamin - Guadeloupe, French West Indies
  Eric Blake - TPC/NHC, Miami, Florida, USA
  Pete Bowyer - Canadian Hurricane Centre, Halifax, Nova Scotia, Canada
  Kevin Boyle - Newchapel Observatory, Stoke-on-Trent, UK
  Jeff Callaghan - BoM, Brisbane, Queensland, Australia
  Simon Clarke - Brisbane, Queensland, Australia
  Tony Cristaldi - NWS Office, Melbourne, Florida, USA
  Roger Edson - University of Guam, USA
  Chris Fogarty - Canadian Hurricane Centre, Halifax, Nova Scotia, Canada
  James Franklin - TPC/NHC, Miami, Florida, USA
  Bruce Harper - Brisbane, Queensland, Australia
  Julian Heming - UK Meteorological Office, UK
  Karl Hoarau - Cergy-Pontoise University, Paris, France
  Greg Holland - BoM, Australia
  Mark Kersemakers - BoM, Darwin, Northern Territory, Australia
  Mark Lander - University of Guam, USA
  Chris Landsea - AOML/HRD, Miami, Florida, USA
  Gary Padgett - Alabama, USA
  Michael V. Padua - Naga City, Philippines
  Michael Pitt - US Navy
  David Roberts - TPC/NHC, Miami, Florida, USA
  David Roth - NOAA/HPC, Maryland, USA
  Matthew Saxby - Queanbeyan, New South Wales, Australia
  Carl Smith - Queensland, Australia
  Phil Smith - Hong Kong, China
  John Wallace - San Antonio, Texas, USA
  Ray Zehr - Colorado State University, Ft. Collins, Colorado, USA

     For each of the survey questions, the format will be as follows:

     (1) the question as it appeared in the original survey

     (2) summary of the responses to each of the possible choices

     (3) some of the comments from various respondents

  Following this I will attempt to present an analysis of the issues
  plus interject my opinions on the subject.

     The monthly feature for July will focus on two types of deep tropical
  systems, very different from each other, but yet the precursors of the
  majority of the world's tropical cyclones:  the monsoon depression and
  the tropical wave (also known as easterly waves).  Easterly waves are
  the primary precursor of Atlantic tropical cyclones which form in the
  deep tropics while monsoon depressions are the parent disturbances for
  most of the tropical cyclones of the North Indian Ocean, the Northwestern
  and South Pacific, and the Australian Region.  The survey questions dealt
  specifically with the operational warning problems caused by both monsoon
  depressions and tropical waves when sustained gale-force winds develop
  before the appearance of "classic" tropical cyclone characteristics.

     There were 28 persons who responded to the survey questions.  For
  some questions, certain persons did not specify an answer, so the total
  number of votes might not always add up to 28.  Also, in some cases the
  respondent was undecided between two of the choices.  In those cases I
  assigned 1/2 vote to each of the two choices.  A word about the comments
  included below:  this article is extremely long as it is, and I could
  not possibly include all the comments which the various respondents
  made.  I have selected certain ones which seem to cover the various 
  issues well, as well as a few which cast a different slant on the 

                    Question #6 - Monsoon Depressions

  (1) The question was:  Monsoon depressions are large, sloppily-formed
      cyclones which are prevalent in the western Pacific (both north and
      south), Australian Region, and in the Indian Ocean.  Sometimes these
      systems produce winds exceeding gale force, or even storm force,
      without having a tight circulation nor well-organized central
      convection.  In pre-Dvorak analysis days, no doubt many of these
      were classified as tropical cyclones.  Do you think the best
      operational warning strategy for monsoon depressions acquiring
      gale-force winds is:

      (A) Name as tropical storms
      (B) Introduce monsoon depression terminology in warnings and
          emphasize presence of gales
      (C) Issue gale warnings for certain areas without describing
          the meteorological phenomenon
      (D) Ignore and hope they'll go away or else transform into "classic"
          tropical cyclones

  (2) Summary of Responses

      (A) Name as tropical storms:       9.0 votes  -  33% 
      (B) Introduce new terminology:    14.5 votes  -  54%
      (C) Issue generic gale warnings:   3.5 votes  -  13%
      (D) Ignore:                        0.0 votes  -   0%

  (3) Some Comments

      Carl Smith (A & B):  "They should be named if they are closed systems
      and produce gale/storm-force winds, however, specific terminology
      should be included in the warnings describing the situation and where
      the gales/storm-force winds are expected."

      Chris Fogarty (C):  "Treat it like a large extratropical LOW--like in
      the Atlantic without getting fancy."

      Chris Landsea (A):  "Handle similarly to what I suggested for sub-
      tropicals.  Name 'em as 'tropical cyclones' operationally, then in
      the Best Track indicate the best 'true' identity."

      Dave Roberts (B):  "During my tenure at JTWC, I would name monsoon
      depressions even though core winds were weak.  Just was simpler to
      do without confusing anyone.  However, model assimilation was another
      issue (TC size).  Would like to see as separate terminology including
      monsoon gyres."

      David Roth (A):  "Name as tropical storms since they have a very warm
      core and usually transition into TCs.  Frances of 1998 and Isidore of
      2002 fit this definition fine, from what I understand, and completed
      the transition."

      Greg Holland (C):  "Definitely NOT tropical cyclones...their winds
      are well removed from what is generally a weakly-defined center (and
      in the Australian Region often over land), and from memory, a lot,
      if not most of them, are substantially cold-cored in the lower
      troposphere...there is actually no need for any changes.  My
      impression is that the current system handles these perfectly
      well by just putting out gale warnings."

      James Franklin (B):  "Issue gale warnings but discuss in context of
      a monsoon cyclone."

      Jeff Callaghan (A):  "Justin in the Coral Sea in March, 1997, was for
      much of its life more like a deep monsoon LOW but had a huge impact
      at sea."

      John Wallace (C):  "There is no need to add more confusion to the TC
      classification system by discerning between true TCs and MDs."

      Julian Heming (B):  "If we are going to have a separate terminology
      for sub-tropical storms in the Atlantic, then there needs to be a
      similar terminology for monsoon depressions, particularly if winds
      exceed gale force."

      Kevin Boyle (B):  "Although winds of >35 kts could be classed as a
      tropical storm, I suppose, to avoid confusion and to enhance aware-
      ness of the system."

      Mark Lander (B):  I used to think that the most sensible thing to do
      for monsoon depressions that had evolved to the point of possessing
      gales was simply to name them as tropical storms.  This is still my
      preferred option, but since the warning agencies seem to have such
      trouble with these things (center location, the warning format of
      point-radius, broad light wind center, etc), I think an out is
      needed.  My 'out' would be to develop a point-band or point-ring
      format for wind distribution.  Then the systems can be numbered,
      and the warning center does not have to over fret the non-standard
      wind distribution.  Also, by the time a MD has true gales in it,
      it is usually well on its way to becoming a conventional TC anyway."

      Matthew Saxby (A):  "If it's a tropical system with a closed
      circulation and gales in at least one quadrant, I think the thing
      should be named and warned on in the normal TC way.  Like I said
      before, any victims aren't going to be impressed with fine legalistic

      Phil Smith (A):  "My reason for choosing Option A is purely one of
      making the general public aware that 'there are dangerous winds about
      somewhere out there' and that they may need to make preparations
      for bad weather conditions.  As I understand it, this practice is
      being taken up by BoM for monsoon LOWs threatening Australian areas
      for this reason.  A negative that could be raised against this prac-
      tice is the likelihood that several circulation centres may develop
      around the periphery and that these will sometimes 'take turns' at
      being the dominant centre.  This could lead to some exceedingly
      erratic paths for some storms if the agency concerned tries to fix
      the centre of the named storm at where the most action is occurring
      from time to time."

      Ray Zehr (B or C):  "Some 'TC size according to RMW' criteria is
      needed as a guideline for naming.  Since multiple TCs can be
      associated with a single monsoon depression (or gyre), you can't
      be naming monsoon depressions.  Of course, a monsoon depression
      can have a TC at its center, i.e., evolve into a TC."

                      Question #7 - Tropical Waves

  (1) The question was:  Primarily in the Atlantic tradewind belt--perhaps
      rarely in other basins--well-organized tropical disturbances (i.e.,
      tropical waves) moving rapidly along can produce gale and/or storm-
      force winds without a closed circulation at the surface.  They
      usually have a mid-level circulation and would no doubt have westerly
      winds at the surface on the equatorward side if they were not moving
      so rapidly (sometimes 25-30 kts).  These often present a much more
      serious threat to marine interests and the Lesser Antilles than some
      "normal" tropical depressions or even weak tropical storms.  What is
      the best operational warning strategy for these?

      (A) Name as tropical storms
      (B) Mention that gales are present in Tropical Weather Outlooks or
          Special Tropical Disturbance Statements
      (C) Introduce new terminology or issue special advisories for these
          gale-bearing waves and emphasize warnings for strong winds

  (2) Summary of Responses

      (A) Name as tropical storms:    5.5 votes  -  20%
      (B) Mention in TWOs or STDSs:  13.5 votes  -  48%
      (C) New terminology:            9.0 votes  -  32%

  (3) Some Comments

      Chris Landsea (A or B):  "Definitely not Option C, but I'm on the
      fence about this one.  I could see either 'A' or 'B', as long as
      the best track indicated that they were troughs rather than a
      tropical cyclone (or even don't include them in the Best Track)."

      Dave Roberts (C):  "Wondering what the statistics are of these waves
      eventually developing into TCs?  Either way, a forecast track with
      intensity and wind radii could easily be developed during its life

      David Roth (B):  "Mention that gales are present in Tropical Weather
      Outlooks or Special Tropical Disturbance Statements AND High Seas
      Forecasts.  There MUST be gale warnings in the High Seas Forecasts
      for these systems, no ifs, ands, or buts.  If not, then 'someone'
      has dropped the ball."

      Eric Blake (A or B):  "Name usually if near land, otherwise
      Option B."

      Greg Holland (B):  "Same comment for monsoon depressions, if they
      are loosely defined at the center.  However, if they have tropical
      cyclone characteristics, then definition should be in Lagrangian
      terms (note that the cloud imagery and our interpretation thereof
      is Lagrangian).  I do note that NHC requires a westerly wind at the
      surface to call these systems, so why change a system that ain't

      James Franklin (B):  "Issue gale warnings, and mention such in TWOs
      and STDSs.  This is what we do now.  I am very much opposed to
      calling a trough a tropical cyclone.  Look, not all hazardous weather
      occurs in tropical cyclones.  For the life of me, I cannot understand
      this desire to call anything hazardous in the tropics a tropical

      Julian Heming (B):  "I think we need to adhere to classical
      definitions of tropical cyclones (closed circulation), but also
      develop ways of warning on the hazards of such systems."

      Mark Lander (A):  "Some of the TCs of 2003 (Claudette) showed that
      these systems can possess gales, and an impressive cloud system, and
      actually not have a distinct well-defined surface vortex.  I think
      that if a persistent, well-organized cloud system (with some of the
      properties of a TC, such as an anticyclonic pattern to cirrus out-
      flow) should be named.  This especially if there is a light wind
      region to the south of the gales (where only a small change in
      intensity or forward speed would result in the immediate formation
      of a surface vortex).  I would bet that the statistics would show
      that persistent well-defined tropical disturbances that acquire
      gales become TCs most of the time, so there is an urgency to get out
      a tropical advisory at the earliest possible time."

      Phil Smith (C):  "Could they be 'named tropical waves' drawing from
      the same pool of names as are used for regular TCs?  They certainly
      present as much danger to shipping and island communities as named
      storms do, and may often have very high winds on the one side. 
      Names are useful for alerting the general public and since these
      waves can easily become true TCs when they slow down a bit, I believe
      it would be a useful practice to help people know that the same
      disturbance being referred to as 'Tropical Wave Adam' has become
      'Tropical Storm Adam'.  And if 'Tropical Wave Adam' simply fizzles
      out without ever becoming 'Tropical Storm Adam', then no harm has
      been done and people have been warned of winds which are dangerous
      to their ships, homes, businesses or other interests."

      Ray Zehr (A):  "I've never liked the criteria of 'closed circulation'
      for weak TCs.  The criteria should be 'closed circulation in center
      relative coordinates'.  I see nothing wrong with explaining to the
      public that a fast-moving vortex has strong winds on one side from
      the direction of motion, and that's it.  I think in the Atlantic
      this occurs often with TDs and extratropical transitions, but
      rarely with TSs, however, it's apparently somewhat common off the
      west coast of Australia."

      Roger Edson (B):  "However!!!  The scatterometer and microwave
      imagery era has shown that it is wrong to assume that all do not
      have westerly winds to the south and a closed circulation.  Those
      'old' assumptions were based on lack of data and a bad use of

      Simon Clarke (C):  "Call them 'Gale Force Tropical Waves'."

      Tony Cristaldi (C):  "Mention that the only reason that the system
      does not have the westerly ground-relative winds needed to be
      designated as a TC is because of its fast forward speed."

                       Analysis and Gary's Opinion

     First of all I'll say that Option D to Question #6 (ignore monsoon
  depressions and hope they'll go away) perhaps sounds facetious, but it
  was not meant as a joke.  I've sometimes gotten the impression that
  they've often been handled that way in the past, particularly by JTWC,
  which has no provision in their operational plan (along with NHC) for
  a tropical depression which might have gale-force winds.   That's not
  a problem for Australia and Fiji whose current definition of a tropical
  depression (tropical LOW in Australia) allows for gale-force winds if
  they are not occurring near the system's center.

     In the survey I voted for Option A (name as tropical storms), but I'll
  restrict that to include only systems for which the gales have begun to
  curve cyclonically around the circulation, even if at some distance from
  the center, and occupying from 1/3 to 1/2 or more of the circulation.
  Most systems at this stage are likely to continue evolving into a
  "classic" tropical cyclone anyway.   I would not name systems with mainly
  a linear band of gales well-removed from the center and which often could
  exist without the presence of the LOW center.   From my experience in
  following such depressions in the Australian Region and South Pacific,
  I have noted that sometimes the gales may be on the equatorward side due
  to a monsoonal westerly-wind burst; at other times on the poleward side
  due to a tight gradient with a subtropical HIGH.

     Following is a quote from an e-mail I received from Cliff Revell,
  who was (I think) formerly a member of New Zealand's Meteorological
  Service.  This comes from a letter Cliff had sent to Steve Ready
  a few years earlier concerning the former WMO Region V requirement
  that a tropical depression must have gales surrounding the center
  in order to be classified as a tropical cyclone:  "A suggestion.  In
  order to maintain consistency with other regions, with past statistics,
  and to exclude those cases when gales occur at a distance from the
  centre in a more or less linear band caused by a strong anticyclone to
  the south, adopt the requirement that the envelope of gale-force or
  stronger winds be curved in a cyclonic sense."

     I must add, though, that Greg Holland and Ray Zehr have raised two
  concerns which should be considered.  As Greg points out, gale-producing
  monsoon depressions can form over land in the northern portions of the
  Australian continent.   As every tropical meteorological text written
  since the time of King Tut points out--tropical cyclones are absolutely 
  a type of marine cyclone and always weaken when they move over land.
  Personally, I think it quite likely that most of these inland monsoon
  depressions have the band of gales to the north due to strong monsoonal
  westerlies and don't fit the cyclonic curvature criteria suggested by
  Cliff Revell.

     Ray Zehr (also Phil Smith) brought up the issue of multiple circu-
  lation centers.  Most of my knowledge of monsoon depressions and gyres
  has come from Mark Lander, and from what Mark has related, monsoon gyres
  typically spawn multiple tropical cyclones, but the entire gyre itself
  only very rarely consolidates into a tropical cyclone (Typhoon Gladys of
  1991 being an example).  The smaller monsoon depression does often sport
  several convective clusters, some of which may exhibit rotation, but
  usually by the time an extensive area of gales has begun to curve around
  the larger center, that center has become dominant and the depression
  goes on to become a conventional tropical cyclone.

     With regard to rapidly translating tropical waves, it is interesting
  to note that while most persons in the tropical cyclone community tend
  to regard a westerly surface wind on the equatorward side an absolute
  requirement for the existence of a tropical cyclone, there are some
  prominent voices (again Ray and Greg) who would define a tropical cyclone
  in terms of center-relative coordinates.    I voted for Option A (to
  name) on the survey, but this was somewhat of a turnaround from the way
  I'd previously thought on the issue.  A couple of systems which helped to
  alter my way of thinking were Chantal (2001) and Claudette (2003).
  Chantal at one point was all but an open wave with 60-kt winds racing
  across the Caribbean.  And Claudette was a very well-developed system
  with a very definite tropical storm appearance in satellite imagery with
  established anticyclonic outflow and 45-kt winds north of the "center",
  but (it was thought) without any westerly winds to the south.  On 8 July
  a reconnaissance aircraft searched in vain for several hours for westerly
  winds and was about to depart the area when it very fortuitously
  discovered a 20-kt southwesterly wind and a very tiny vortex.  So we then
  had an "instant" tropical storm.  (I would add that I'm not in favor of
  naming strong tropical waves which exhibit very little if any vorticity
  and/or outflow, and which have substantial easterly winds on the equator-
  ward side.  Such systems are not likely to develop quickly into tropical

     Somehow it seems a little inconsistent to issue a full advisory
  package (public advisory, forecast/advisory, discussion bulletin and
  strike probabilities) for a 25-kt tropical depression which may not
  be forecast to reach tropical storm intensity for 24-48 hours, but to
  simply relegate information on a gale or storm-force tropical wave to
  the TWOs and gale warnings buried down in the High Seas Forecasts.  If
  they're not going to be named, then STDSs should be issued at least every
  six hours.    Also, Roger Edson brings up a good point that even if a 
  reconnaissance crew fails to find westerly winds, how do we know for sure
  they're not there?

     I can't speak for the general public in the Lesser Antilles or other
  Caribbean nations where these systems usually present a threat, but it
  is an unarguable point that among the U. S. general public, when a system
  is named, the interest jumps by an order of magnitude.    And not just
  among the general public.  Following is an excerpt from the report on
  Hurricane Claudette in the July, 2003, summary:

        The following quote from an e-mail written by Kenneth J. Schaudt
     of Marathon Oil Company illustrates how the attention of the public
     and other concerned parties spikes up when a tropical storm is named:
     "Much of the United States' natural gas is produced in the Gulf of
     Mexico.  Since the threat of tropical storms may shut down production
     briefly, the market for natural gas responds to the perceived threats.
     On the 8th (of July) at 1806 UTC, the Special Tropical Disturbance
     Statement declaring Tropical Storm Claudette hit the wire.  Within
     three minutes, the price of natural gas had jumped 10 cents."

  (Regarding the attention-grabbing power of a name, I know from several
  of my Australian correspondents that the same is true Down Under.)

     Regarding consistency with past practices, I think it is very likely
  that prior to the satellite era and the development of the Dvorak method
  of intensity analysis, and consequently a major emphasis being placed
  on organized central convection, many stronger monsoon depressions were
  classified as tropical storms in the areas of the world where they are
  prevalent, just as in the Atlantic in earlier years no doubt many of the
  "tropical" cyclones in the Best Track file were in reality subtropical
  systems.     And I also think it highly probable that many of the short-
  lived Atlantic systems whose tracks are shown beginning just east of the
  Lesser Antilles and then disappearing in the central Caribbean were
  likely open tropical waves with gale-force or higher winds.  Most of
  these were included in the Best Track file based on island reports of
  tropical storm winds, the assumption being that if sustained gale-force
  winds were present, then more than likely there was a surface

     So, to recap, I personally am in favor of "bending the rules" a little
  to name and treat as tropical storms systems which at a certain point in
  time may not have attained quite all the characteristics of "classic"
  tropical cyclones, but which can pose a significant threat to life and
  property and which likely will eventually evolve into "classic" tropical
  storms.  There is nothing anomalous here--many systems have been named 
  which were in truth much closer in nature to a subtropical storm than to 
  a true tropical cyclone.  It seems that this is the best way to help 
  reduce confusion and achieve the ultimate goal of minimizing loss of life
  and mitigating damage.  As Mark Lander has expounded many times, having 
  the initial tropical cyclone advisory refer to a system near or exceeding
  hurricane intensity is not in the best interest of achieving this goal.

                             ACTIVITY BY BASINS

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

  Activity for July:  1 tropical depression

                         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:
  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.

                    Atlantic Tropical Activity for July

     No tropical storms or hurricanes formed in the Atlantic basin during
  the month of July.   This isn't anything out of the ordinary, as the
  annual average of named storms is about 4 every 5 years, with a hurricane
  developing about every third year.  Over the past 25 years, July has been
  stormless in 13 years, or about half the time.  The only intense July
  hurricane (Category 3 or higher on the Saffir/Simpson scale) since 1950
  was Hurricane Bertha in 1996.   Neither did any tropical depressions form
  during July until the final day of the month, when Tropical Depression 01
  developed during the afternoon off the Georgia coast, becoming Tropical
  Storm Alex the next day.  On 3 August Alex intensified into a Category 2
  hurricane and passed very close to Cape Hatteras as it began to move
  northeastward away from the U. S. mainland.  After weakening slightly on
  the 4th, Alex re-intensified on the 5th into a Category 3 hurricane as it
  scooted northeastward over the warm Gulf Stream waters south of the
  Canadian Maritimes.  The report on Hurricane Alex will be included in the
  August summary.

     There were, however, a couple of weaker tropical disturbances worthy
  of mention.  A small area of disturbed weather developed on the morning
  of 8 July about 240 nm southwest of Bermuda.  During the afternoon a
  small surface LOW center formed and moved east-northeastward, passing
  very near Bermuda early on the 9th.  According to Jack Beven, there was
  just enough of a wind and pressure perturbation at Bermuda to show that
  the circulation did exist at the surface.  The lowest SLP recorded on
  the island was only 1019 mb.  Convection associated with the LOW remained
  poorly-organized and the system soon encountered cooler SSTs after
  passing Bermuda.

     Disturbed weather developed off the east coast of Florida and extended
  northeastward from the Bahamas for several hundred miles late in the
  third week of July.  This was associated with an upper-level LOW and a
  broad surface trough.  A weak LOW formed on the 24th about 285 nm south-
  east of Cape Hatteras.  By the morning of the 25th the LOW was centered
  about 150 nm east-southeast of Cape Hatteras, moving north-northwestward
  at about 12 kts with limited thunderstorm activity.   During the early 
  morning hours of 26 July convection increased significantly, the LOW then
  being located around 200 nm south of Long Island.  Maximum winds were 
  estimated to be 20-25 kts northeast of the center, and there was a
  possibility that if thunderstorm activity continued to increase near the
  center, a tropical or subtropical depression might develop.   However, 
  by midday the LOW was beginning to merge with a frontal zone, so tropical
  cyclone formation was no longer considered likely.


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

  Activity for July:  3 tropical depressions
                      1 tropical storm
                      1 hurricane
                      1 intense hurricane

                        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

                Northeast Pacific Tropical Activity for July

     Over the period 1971-2003, the Northeast Pacific basin's statistics
  for July are:  3.7 named storms, 2.0 hurricanes, and 1.1 intense hurri-
  cane.  July of 2004 was pretty close to average with 3 named storms,
  2 hurricanes, and 1 intense hurricane.  Darby became the first Eastern
  Pacific intense hurricane since Kenna in October, 2002.  All three of
  the storms formed well off the Mexican coast and moved generally west-
  northwestward with minimal effects on the coastline.  Reports follow
  on these three storms--a special thanks to John Wallace for writing the
  summaries for Blas and Celia.

     In addition to the three named storms, there were also three tropical
  depressions for which advisories were issued.  The first of these formed
  very early in the month well to the southwest of Cabo San Lucas on the
  southern tip of the Baja California Peninsula.  Tropical Depression 02E
  formed around 1200 UTC on 2 July about 650 nm southwest of Cabo San 
  Lucas and moved west-northwestward, dissipating by 03/1800 UTC about 
  850 nm west-southwest of the Cabo.    Maximum winds were estimated at 
  25 kts.  Also during the first week of July, Tropical Depression 01C 
  formed in the Central North Pacific about 625 nm southeast of Johnston 
  Island.  The first advisory was issued by CPHC at 0300 UTC on 5 July, 
  and the final one issued at 0300 UTC the next day when it became apparent
  the system was dissipating.   Maximum winds in this depression were also
  estimated at only 25 kts.

     Finally, advisories were initiated on Tropical Depression 06E at 0900
  UTC on 29 July with the center located about 415 nm south-southwest of
  Cabo San Lucas.  However, the final advisory was issued only 18 hours
  later, locating the dissipating center about 215 nm west-southwest of its
  point of origin.  In the case of TD-06E, the remnant LOW held together
  as it drifted west-southwestward across the expanse of the Eastern North
  Pacific.  By late on 1 August convection had become re-established near
  the center of the LOW so advisories were begun again on the system at
  02/0300 UTC.   The center was placed roughly 1200 nm west-southwest of
  the southern tip of Baja California, and winds were estimated at 30 kts.
  The depression was located over warm SSTs and in a region of low shear,
  and intensification to near hurricane strength was initially forecast,
  but the system failed to respond to its apparently favorable environ-
  ment.   Visible imagery on the 3rd and a 03/1440 UTC QuikScat overpass
  indicated that the depression no longer had a well-defined closed surface
  circulation and had degenerated into an elongated trough with embedded
  swirls and only a narrow band of weak convection.  The final advisory
  at 03/2100 UTC placed the dissipating center about 1500 nm west-southwest
  of Cabo San Lucas.

                         TROPICAL STORM BLAS
                            12 - 15 July

  A. Storm Origins

     Tropical Storm Blas formed from a tropical wave which had crossed
  Central America into the Eastern Pacific on 8 July.  On 12 July an
  area of persistent disorganized convection that had been flaring up in 
  the Eastern Pacific for several days had finally consolidated by midday,
  warranting its upgrade to Tropical Depression Three-E at 1500 UTC on
  12 July when located approximately 300 nm south-southwest of Manzanillo,
  Mexico.   The depression tracked steadily northwestward, under the
  influence of a ridge stationed over the United States Southwest.

  B. Synoptic History

     The depression officially strengthened to Tropical Storm Blas at 
  0300 UTC on 13 July when centered about 265 nm southwest of Manzanillo.
  The nascent Blas had the distinction of being a very large storm, with
  storm-force wind radii that maxed out at 200 nm in the western quadrant
  on the 13th and into the 14th as it accelerated northwestward at the
  surprising speed of 17-18 kts.  Blas reached its peak 1-min avg MSW of
  50 kts, with a CP of 994 mb, at 0900 UTC on 13 July, an estimate which
  the NHC considered conservative.

     Blas began weakening on the 14th as it tracked into unfavorably cool
  waters.  Its broad circulation remained robust--ship ELYS4 reported a
  35-kt wind 100 nm from the center at 0600 UTC on the 14th, though the
  peak MSW overall was only 40 kts.  Blas had dropped below storm strength
  by 2100 UTC that day and, as is typical of weakening NEP cyclones,
  decelerated and turned to the west-northwest along with the low-level
  trade winds.    Its convection having completely collapsed, the last
  advisory was issued on Tropical Depression Blas at 0300 UTC on 15 July,
  the weakening center being located about 500 nm due west of Cabo San
  Lucas on the southern tip of the Baja California Peninsula.   Not
  surprisingly, the large remnant vortex took some time to spin down, and
  was dimly evident in visible imagery as late as the 19th.

  C. Damage and Casualties

     Though squalls affected Baja California, no known casualties or damage
  were caused by Tropical Storm Blas.

  (Report written by John Wallace)

                           HURRICANE CELIA
                             19 - 25 July

  A. Storm Origins

     As Tropical Storm Blas weakened and dissipated to the northwest,
  another tropical cyclone quickly formed in its wake.  A vigorous
  tropical wave moved off the western coast of Africa on 5 July and 
  tracked uneventfully across the Atlantic and Caribbean.  The wave 
  ultimately reached the Eastern Pacific, spawning a compact LOW which 
  was evident as early as the 17th.  As the system tracked roughly 
  westward it became better organized and was upgraded to Tropical 
  Depression Four-E at 0300 UTC on 19 July when centered approximately 
  550 nm south-southwest of Cabo San Lucas.

  B. Synoptic History

     A ridge to the north steered TD-04E slowly to the west with slight
  oscillations.  Its potential intensity was uncertain, due to the 
  conflicting factors of nearby stable air but also low shear and warm
  SSTs.  Even so, the depression strengthened to Tropical Storm Celia at
  2100 UTC on 19 July when located about 600 nm south-southwest of Cabo
  San Lucas.  Celia was as remarkably small as its predecessor Blas had
  been large:  the gale-radius was only 60 nm, a value which varied little
  throughout the cyclone's lifetime--even at its peak--challenging "midget"

     Celia tracked uneventfully westward and steadily intensified, after 
  a slight weakening late on the 20th and into the 21st due to interference
  from an upper-level LOW.  However, it managed to avoid entraining nearby
  stable air into its circulation.  Satellite detection of a mostly-closed
  eyewall warranted its upgrade to a hurricane at 0300 UTC on 22 July.  The
  storm at this time had moved to a position about 750 nm southwest of Cabo
  San Lucas.  Celia reached its peak MSW of 70 kts, with an estimated CP of
  985 mb, six hours later at 22/0900 UTC.

     Celia weakened rapidly after its peak, probably due to both cooler
  water and entrained stable air, courtesy of an interfering upper-level
  LOW.  By 2100 UTC on the 22nd the convection had largely collapsed,
  though the weakening trend stabilized near minimum tropical storm
  strength.  Periodic deep convection and a good LLCC allowed it to hold
  on to storm status as it tracked westward.  It seems that the entrainment
  of dry air decreased, shear remained low, and SSTs temporarily became a
  little warmer.

     On the 24th, however, Celia weakened to a depression, and turned 
  toward the west-northwest with a slight increase in speed as it moved
  with the low-level flow.  Convection remained remarkably tenacious for
  such a small cyclone, and the last warning was not issued until late on 
  25 July--at 2100 UTC--placing the weakening LLCC about 1375 nm west-
  southwest of the tip of Baja California.  The remnant vortex remained 
  evident in satellite imagery until late on the 27th, when it dissipated
  several hundred miles southeast of Hawaii.

  C. Damage and Casualties

     There were no known casualties or damage resulting from Celia.

  (Report written by John Wallace)

                             HURRICANE DARBY
                           26 July - 1 August

  A. Storm Origins

     A tropical wave moved westward across the coast of Africa on 12 July
  and continued across the Atlantic and Caribbean, reaching the Eastern
  Pacific on 20 July.  The system showed the first signs of organization
  on the 24th well to the south-southwest of Manzanillo, Mexico.   The
  disturbance gradually became better organized and had developed into
  Tropical Depression 05E by 1800 UTC on 26 July when it was centered
  approximately 700 nm south-southwest of Cabo San Lucas on the southern
  tip of the Baja California Peninsula.       Six hours later Dvorak
  classifications from SAB and TAFB had reached T2.5, so TD-05E was
  upgraded to Tropical Storm Darby.  The circulation was still in its
  formative stages and had not completely separated from the ITCZ.

  B. Synoptic History

     Tropical Storm Darby's convective structure became increasingly better
  organized during the 27th and by 1800 UTC the estimated MSW had reached
  60 kts--just shy of hurricane status.  There were some indications that
  a banding-type eye was trying to develop, but its appearance in satellite
  imagery was rather transient for the next 12 hours.  However, SSM/I
  microwave data at 28/0336 and 28/0507 UTC clearly indicated that Darby
  had developed a 20-25 nm diameter eye embedded in a round CDO, and auto-
  mated ODT values were around 69 kts.  Satellite CI estimates ranged from
  55 to 77 kts, but taking all the evidence into consideration, Darby was
  upgraded to the season's second hurricane at 28/0900 UTC when located
  approximately 835 nm southwest of Cabo San Lucas.  Darby at this time
  was moving west-northwestward at 11 kts around a subtropical ridge.
  Initially, the hurricane was forecast to peak at 80 kts and then begin
  to weaken as it encountered cooler SSTs.  However, at 2100 UTC the cloud
  pattern had improved significantly and T-numbers had increased to 5.0,
  so the MSW was increased to 90 kts.

     A further surprise was in store.   At 0600 UTC on 29 July Dvorak
  T-numbers from both TAFB and SAB had reached 6.0, or 115 kts.  Darby
  had undergone rapid intensification over sub-27 C water with the MSW
  increasing from 35 kts to 105 kts in 54 hours.  The MSW was set at
  105 kts instead of 115 kts due to the fact that Darby was over 26 C
  water, and the forecaster felt that downward mixing of the strong winds
  was likely not occurring due to the cooler and more stable boundary
  layer.  Nonetheless, Darby had become the first Category 3 or higher
  hurricane in the Eastern North Pacific since the very intense and
  destructive Hurricane Kenna in October, 2002.

     Darby's tenure as a major hurricane, however, was not to be for long.
  By 29/1500 UTC the eye was becoming less distinct and winds were dropped
  to 100 kts, and six hours later the eye was no longer visible and the
  MSW was further reduced to 90 kts.    The demise of Hurricane Darby was
  rather quick as it moved over cooler SSTs and into increasing vertical
  shear.  Only 24 hours after reaching its peak of 105 kts, Darby was only
  a minimal hurricane, and six hours later was a 55-kt tropical storm.
  Eastern North Pacific tropical cyclones have a higher "death rate" caused
  by systems moving over cold SSTs without encountering a baroclinic zone
  more so than in any other basin.  Typically when systems moving north-
  westward or west-northwestward lose most of their deep convection and
  become shallow systems, they turn westward and move with the low-level
  trade winds.  Darby was no exception to this as it began to track west-
  ward after crossing 130W.

     By 2100 UTC on 30 July Darby had been reduced to a swirl of low and
  mid-level clouds with isolated patches of deep convection to the north-
  east of the center.   Satellite intensity estimates ranged from 35 to
  65 kts, and a high resolution QuikScat overpass at 1446 UTC showed a
  50-kt vector north of the center, so the intensity was set at 50 kts.
  However, the MSW was reduced to 40 kts six hours later, and at 1200 UTC
  on the 31st Darby was downgraded to a tropical depression.   Darby had
  crossed 140W into the Central North Pacific by 0000 UTC on 1 August.
  Although the depression was moving over warmer water, it was running into
  strong southwesterly vertical shear.   CPHC issued the final advisory on
  Darby at 01/0600 UTC, placing the dissipating center about 750 nm east
  of Hilo, Hawaii.  The remnants of Darby continued westward, bringing
  rainfall totals of up to 150 mm in some parts of Hawaii.

  C. Damage and Casualties

     No reports of damage or casualties resulting from Hurricane Darby
  have been received.

  (Report written by Gary Padgett)


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

  Activity for July:  2 tropical storms **
                      1 typhoon

  ** - one of these classified as a tropical storm only by China (NMCC)

                         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).  Also, Huang Chunliang of Fuzhou City, China,
  sends data taken from synoptic observations around the Northwest
  Pacific basin.  A very special thanks to Michael and Chunliang for
  the assistance they so reliably provide.

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

                Northwest Pacific Tropical Activity for July

     After a very active June with five typhoons churning Northwest Pacific
  waters, the month of July was rather quiet by comparison.  Three tropical
  storms formed, with only one reaching typhoon status.  Tropical Storm
  Kompasu/Julian formed just before mid-month and trekked westward, making
  landfall near Hong Kong as a minimal tropical storm.  Late in the month
  Typhoon Namtheun formed roughly 500 nm northeast of Guam and a like
  distance to the southeast of Iwo Jima.    Namtheun moved northwestward,
  then turned westward and moved south of Honshu toward a landfall on the
  island of Shikoku.   The third storm was unnamed, being classified as
  a tropical storm by only NMCC and the Guangdong Regional Meteorological
  Centre (GRMC).  All the other warning agencies treated this system as
  only a tropical depression or low-pressure area, but wind observations
  recorded at several stations in southeastern China strongly suggest that
  this system was a tropical storm.   A report on this system, compiled and
  sent by Huang Chunliang of Fuzhou City, follows.    Reports on the other
  two named cyclones also follow, the one on Kompasu authored by Kevin
  Boyle.  A special thanks to Kevin and Chunliang for their assistance.


     For the past several months Huang Chunliang has been preparing and
  sending tables summarizing the MSW estimations from the various TCWCs.
  Chunliang was away at Shanghai for job-related training for most of the
  months of July and August and was not able to complete the MSW tables
  for the June typhoons.   Following are the tables he recently sent for
  Typhoon Mindulle and Typhoon Tingting.

  == Typhoon 10W/MINDULLE/0407/IGME (Jun 21-Jul 4, 2004) ==

  TCWC       Storm ID                              PEAK MSW (kt)
  JTWC       Typhoon 10W (MINDULLE)                125
  JMA        Very Severe Typhoon 0407 (MINDULLE)    90
  PAGASA     Typhoon IGME                          105
  NMCC       Typhoon 0407 (MINDULLE)               100
  HKO        Typhoon MINDULLE (0407)                90
  CWB        Moderate Typhoon 0407 (MINDULLE)       90

  == Typhoon 11W/TINGTING/0408 (Jun 24-Jul 4, 2004) ==

  TCWC       Storm ID                              PEAK MSW (kt)
  JTWC       Typhoon 11W (TINGTING)                80
  JMA        Very Severe Typhoon 0408 (TINGTING)   85
  NMCC       Typhoon 0408 (TINGTING)               80
  HKO        Typhoon TINGTING (0408)               --*
  CWB        Moderate Typhoon 0408 (TINGTING)      --#
  Note 1 (*): HKO never issued any real-time warnings on this typhoon,
  which remained outside their AOR throughout its life.

  Note 2 (#): CWB data was insufficient for me when I was away in

                         TROPICAL STORM KOMPASU
                       (TC-12W / TS 0409 / JULIAN)
                              13 - 16 July

  Kompasu: contributed by Japan, is the compass, a v-shaped device for
           describing circles or arcs; also the name of the constellation

  A. Storm Origins

     At 0600 UTC on 12 July a weak, cycling area of deep convection was 
  first mentioned in JTWC's STWO and located approximately 500 nm southeast
  of Okinawa.  Animated multi-spectral imagery revealed a possible weak
  LLCC associated with this system.   An upper-level analysis indicated
  that the disturbance was within an area of weak shear and weak diffluence
  aloft.  The potential for development into a significant tropical cyclone
  at this point was assessed as poor.  This was upgraded to fair status in
  a re-issued advisory at 12/1930 UTC.

     A TCFA was issued at 13/0230 UTC after the system had become better 
  organized.  The LLCC was well-developed at this time, but exposed as 
  seen in multi-spectral imagery.  A QuikScat pass also showed a well-
  developed tight vortex with the associated deep convection propagating 
  toward the southern end of an analyzed shear line.   The first warning 
  on Tropical Depression 12W was issued at 13/0600 UTC with the centre 
  located 340 nm south-southeast of Okinawa and moving toward the 
  west at 8 kts.  Even though this system was exiting an area of high 
  vertical shear, the dynamical aids did not indicate any further 
  development nor did they initialize the storm very well.   Pint-sized 
  TD-12W spent the rest of the day tracking westward and accelerating, 
  its forward speed reaching 17 kts by 1800 UTC.  The baby tropical 
  cyclone was christened Kompasu following JMA's upgrade to tropical 
  storm intensity at 0000 UTC on the 14th.   (PAGASA named the 
  depression Julian at 13/1200 UTC when it entered that agency's AOR.)

  B. Synoptic History

     JTWC upgraded Kompasu to a tropical storm at 14/0600 UTC when the
  system was located 180 nm east-southeast of Kaoshiung, Taiwan.  Kompasu
  was still moving briskly toward the west or west-northwest under the
  influence of a mid-level steering ridge to the northeast.  The system
  continued to exhibit an exposed LLCC due to continued shearing from the
  east.  However, a little strengthening had been occurring and the MSW
  reached 40 kts at 14/1200 UTC.  At this time Kompasu unexpectedly turned
  west-southwestwards, and this heading ensured that the centre would pass
  south of Taiwan.

     Tropical Storm Kompasu/Julian did not change a great deal during the 
  15th.   A peak intensity of 45 kts had been reached at 14/1800 UTC and 
  this intensity was maintained throughout the following day.  The radius 
  of gale-force winds fluctuated in succeeding JTWC warnings, but to give
  the reader some idea of Kompasu's minute size, 34-kt wind radius never
  exceeded 50 nm during the maximum intensity.  An interesting possibility 
  is that a tropical cyclone, similar to Kompasu, might have escaped
  unnoticed in the pre-satellite era, especially one which did not make
  landfall near a population centre like Hong Kong.

     At 0000 UTC on 16 July Tropical Storm Kompasu was 85 nm southeast of
  Hong Kong and moving west-northwestward at 10 kts.  The system shifted
  to a more poleward track and came ashore near Hong Kong at approximately
  16/0900 UTC.  Kompasu was barely at tropical storm intensity by the time
  it made landfall.    The LLCC proceeded northward, leaving behind the
  upper-level circulation which was being sheared toward the southwest.
  The final warning was issued by JTWC at 16/1200 UTC when the centre was
  continuing northward 40 nm east of Hong Kong.  JMA continued to monitor
  Kompasu as a tropical depression for another six hours before that agency
  also dissipated the storm.

  C. Meteorological Observations

     Waglan Island reported a 10-min sustained MSW of up to 65 kts at 
  16/0900-1000 UTC.  The lowest pressure of 996 mb was recorded between
  0500-0600 UTC.   (The AWS at Waglan Island sits more than 75 m above

     The following report was sent by Huang Chunliang.

     According to the HKO warnings, Tropical Storm Kompasu (0409) made
  landfall over Sai Kung at around 16/0700 UTC, when it was about 25 km to
  the east of Hong Kong Observatory Headquarters, its closest approach,
  with a MSW of 40 kts and a CP of 990 hPa.

     The HKO report on TS Kompasu can be found at the following link:>

     In Guangdong Province, the coastal region near the mouth of Pearl
  River reported sustainded winds of Beaufort Force 7 to 8, gusting to
  Force 9 to 10 during the storm.   Pingshan & Longqi, both located in
  Shenzhen City, recorded peak gusts to 50.5 kts, while the Gulf of Daya
  (Huizhou City) & Guishan (Zhuhai City) both reported gusts topping
  46.7 kts.

  D. Damage and Casualties

     News reports indicated that Tropical Storm Kompasu only caused minor 
  damage in Hong Kong.  Three people were injured as a result of wind-
  borne debris.     However, many transportation services were either
  cancelled or ran on reduced schedules, and the stock market, banks and
  other institutions were closed.  Emergency shelters were opened for the 

  E. Addendum to July Tropical Cyclone Tracks File

     Following is the MSW comparison table prepared and sent by Huang
  Chunliang.  This was unavailable at the time the July tracks file was

  == Tropical Storm 12W/KOMPASU/0409/JULIAN (Jul 11-16, 2004) ==

  TCWC       Storm ID                              PEAK MSW (kt)
  JTWC       Tropical Storm 12W (KOMPASU)          45
  JMA        Typhoon 0409 (KOMPASU)                45
  PAGASA     Tropical Storm JULIAN                 40*
  NMCC       Tropical Storm 0409 (KOMPASU)         45
  HKO        Tropical Storm KOMPASU (0409)         45
  CWB        Weak Typhoon 0409 (KOMPASU)           40

  Note (*): The MSW is merely the "peak" value based on the limited
  warnings released only when the storm was travelling within the
  restricted AOR, so it may have not been the real peak.

  (Report written by Kevin Boyle with contributions by Huang Chunliang.)

                            TYPHOON NAMTHEUN
                           (TC-13W / TY 0410)
                           24 July - 1 August

  Namtheun: contributed by Laos, is the name of a river--one of the
            tributaries of the Mekong River

  A. Storm Origins

     The origins of July's only typhoon lay in an area of convection which
  formed on 23 July about 470 nm northeast of Guam and was persistent.
  Animated multi-spectral and water vapor imagery revealed upper-level
  divergence into an upper-level LOW east of a possible LLCC.  A QuikScat
  pass depicted a very weak circulation embedded in an elongated area of
  broad troughing, and an upper-level analysis suggested an environment
  of low vertical shear and fair divergence.  At 24/0600 UTC the system
  was relocated two degrees poleward to a point approximately 540 nm
  northeast of Guam.  The potential for development was upped to fair at
  24/1100 UTC as deep convection was increasing over the LLCC.  A recent
  QuikScat pass indicated stronger winds in the northeast quadrant, but
  the core of the circulation remained weak.  An upper-level analysis
  indicated that anticyclonic flow was centered over the LLCC with good
  outflow in the equatorward direction.

  B. Synoptic History

     JMA classified the system as a 30-kt tropical depression at 24/1200
  UTC, and JTWC issued a TCFA at 24/1400 UTC.  The area of convection was
  quasi-stationary approximately 530 nm northeast of Guam, and satellite
  imagery indicated that deep convection was continuing to increase over
  the LLCC, even though a recent QuikScat pass showed that the LLCC was
  still very disorganized and not co-located with the mid-level rotation.
  JTWC's first warning on Tropical Depression 13W was issued at 0000 UTC
  on 25 July.  The center was located about 550 nm east-southeast of Iwo
  Jima and was drifting north-northwestward at 2 kts.   A mid-level
  steering ridge to the northeast was forecast to continue guiding the
  tropical cyclone to the north-northwest.  At 25/1200 UTC both JTWC
  and JMA upgraded the depression to tropical storm status with the latter
  agency assigning the name Namtheun.   Satellite CI estimates were 35
  and 55 kts, but a 25/0409 UTC CIMSS AMSU intensity estimation product
  showed the system to be near 992 mb, and recent 85-GHz SSM/I passes
  revealed a possible mid-level eye forming.  The MSW was set at 50 kts
  in JTWC's warning and at 40 kts (10-min avg) in JMA's warning.  By
  1800 UTC Tropical Storm Namtheun was passing approximately 400 nm east
  of Iwo Jima, still tracking northwestward.

     The 26th of July was a day of rapid intensification for Namtheun.
  JTWC upgraded the system to a 65-kt typhoon at 26/0000 UTC when it was
  centered about 370 nm east of Iwo Jima.  The MSW was bumped up to 90 kts
  at 0600 UTC based on CI estimates of 77 and 102 kts.  A 26/0328 UTC
  AMSR-E pass revealed a 15-nm eye surrounded by a well-defined banding
  feature.  At the same time JMA increased the intensity (10-min avg) from
  55 kts to 80 kts.     By 1800 UTC winds had increased to an estimated
  115 kts with the typhoon located approximately 300 nm east-northeast of
  Iwo Jima.  This, however, proved to be Namtheun's peak intensity.  (JMA's
  peak 10-min avg MSW was 85 kts with an attendant CP of 945 mb.)  At its
  peak intensity Namtheun was a rather small typhoon with gales covering
  an area about 200 nm in diameter.  The radius of typhoon-force winds was
  estimated at 30 nm.

     Typhoon Namtheun continued tracking steadily northwestward on the 27th
  as it slowly began to weaken.    The eye was no longer evident in EIR
  imagery by 1200 UTC and the MSW was brought down to 105 kts, and at 1800
  UTC the intensity was reduced further to 90 kts.     Namtheun was then
  centered about 360 nm southeast of Tokyo and moving northwestward at
  10 kts.     On 28 July Namtheun's track changed to more of a west-
  northwesterly heading.  The storm held its 90-kt intensity until 1200 UTC
  when it was lowered to 80 kts.     By 0000 UTC on 29 July Namtheun was
  moving due westward at around 4 kts as it passed a little over 200 nm
  due south of Tokyo, and this westerly motion continued throughout the
  day.  The MSW remained pegged at 80 kts until 29/1800 UTC when it was
  decreased slightly to 75 kts.   A 29/1143 UTC SSM/I pass in the 37-GHz
  band revealed a ragged, 50-nm diameter eye.  Animated water vapor imagery
  showed that deep convection in the northwest quadrant was decreasing as
  the system encountered northerly flow aloft and drier low-level inflow
  from Japan.

     Typhoon Namtheun continued to move generally westward south of Japan
  on the 30th.   At 1200 UTC the cyclone was centered approximately 280 nm
  southwest of Tokyo.   JTWC reduced the MSW to 65 kts, based on CI esti-
  mates ranging from 55 to 77 kts plus a UW-CIMSS CP estimate of 975 mb,
  which would correspond to a MSW of around 66 kts.  Drier air from Japan
  had continued to erode the convection in the western semicircle of the
  storm with deep convection now restricted to the eastern quadrants.
  JTWC downgraded Namtheun to tropical storm status at 30/1800 UTC with
  CI estimates still ranging from 55 to 77 kts.  Interestingly, JMA main-
  tained Namtheun as a typhoon for another 18 hours after JTWC's downgrade.
  The storm's heading became increasingly northwesterly on 31 July as it
  tracked around the southwestern periphery of the steering ridge east of
  Japan.  At 31/0600 UTC Namtheun was centered approximately 80 nm east-
  southeast of Iwakuni, Japan, moving northwestward at 11 kts.  JTWC's
  peak MSW was 55 kts, but JMA was still treating Namtheun as a minimal
  typhoon.  By 1200 UTC the center had moved inland over the Japanese
  island of Shikoku, and by 1800 UTC had crossed western Honshu and emerged
  into the Sea of Japan.

     At 0000 UTC on 1 August Namtheun's center was in the Sea of Japan
  about 105 nm east of Busan, South Korea, tracking slowly northwestward.
  Winds were down to 35 kts as a result of terrain-induced weakening; also,
  the LLCC was lagging behind the upper-level circulation due to increased
  shear.   At 01/0600 UTC the cyclone was moving slowly northward east of
  South Korea.  Satellite CI estimates ranged from 25 to 35 kts, but JTWC
  deemed the system to be extratropical and issued their final warning.
  JMA carried Namtheun through one more warning cycle, then downgraded the
  system to a depression and issued their final warning at 1200 UTC.

  C. Meteorological Observations

     Karl Hoarau sent me some hourly observations from the station at
  Murotomisaki (WMO 47899).  The eye of Typhoon Namtheun passed 18 nm to
  the south of the station around 0200 UTC on 31 July.  The storm had
  already been downgraded by JTWC but was still being carried as a typhoon
  by JMA.  The following pressures have been reduced to sea level, and the
  winds represent 10-min mean winds.

  30 July at 2100 UTC    991.2 mb       51 kts
             2200 UTC    989.7 mb       70 kts
             2300 UTC    988.4 mb       72 kts
  31 July at 0000 UTC    986.8 mb       77 kts
             0100 UTC    984.9 mb       87 kts
             0200 UTC    984.2 mb       91 kts
             0300 UTC    985.6 mb       76 kts
             0400 UTC    989.6 mb       68 kts
             0500 UTC    992.3 mb       53 kts

     One fact which should be kept in mind is that the Murotomisaki station
  is located on a cape at an elevation of 185 metres.  (A special thanks to
  Karl for sending these observations.)

  D. Damage and Casualties

     I have received no reports of damage of casualties resulting from
  Typhoon Namtheun.

  E. Additional Observations

     At the last minute I received a report from Huang Chunliang of
  observations from Japanese stations.  I have included the report
  essentially just as he sent it.   A special thanks to Chunliang for
  sending the data.

  NOTE: To convert metres/second (m/s) to knots approximately, just
  double the m/s:  e.g., 35 m/s ~= 70 kts.  To convert precisely,
  divide m/s by 0.51444:  e.g., 35 m/s = 68 kts.

  {Part I}. Landfalls (base on the JMA warnings)

  1. Severe Typhoon 0410 (NAMTHEUN) made landfall in western Kochi
  Prefecture around 31/0700 UTC with a MSW of 35 m/s and a CP of 980 hPa.

  2. Typhoon 0410 (NAMTHEUN) made landfall near Hiroshima City, Hiroshima 
  Prefecture around 31/1230Z with a MSW of 23 m/s and a CP of 992 hPa.

  {Part II}. Top-5 storm totals [29/1500-02/1500Z]

  Ranking    Prefecture        Station           Rainfall (mm)
  01         Tokushima         Asahimaru         1243
  02         Nara              Mt.Hidegatake     1153
  03         Tokushima         Kitou              980
  04         Tokushima         Fukuharaasahi      936
  05         Kochi             Shigetou           772

  {Part III}. Top-5 daily rainfall obs

  Ranking    Prefecture        Station           Rainfall (mm)
  01         Tokushima         Asahimaru         588*[31/1500-01/1500Z]
  02         Nara              Mt.Hidegatake     588 [30/1500-31/1500Z]
  03         Tokushima         Fukuharaasahi     516 [30/1500-31/1500Z]
  04         Kochi             Yanase            514 [30/1500-31/1500Z]
  05         Tokushima         Kitou             512*[31/1500-01/1500Z]

  {Part IV}. Top-5 hourly rainfall obs

  Ranking    Prefecture        Station           Rainfall (mm)
  01         Kochi             Nakamura          117*[01/1540-01/1640Z]
  02         Kochi             Shigetou          110*[01/0000-01/0100Z]
  03         Ehime             Chikanaga         104*[01/1410-01/1510Z]
  04         Kochi             Motoyama           92 [01/0910-01/1010Z]
  05         Kochi             Kubokawa           91*[01/1140-01/1240Z]

  {Part V}. Top-5 peak sustained wind (10-min avg) obs

  Ranking   Station                                     Peak wind (mps/dir)
  01        Murotomisaki, Kochi (WMO47899, Alt 185m)    47.7/E   [31/0210Z]
  02        Hiwasa, Tokushima (JMA71266, Alt 3m)        22  /E   [31/0310Z]
  03        Shionomisaki, Wakayama (WMO47778, Alt 73m)  19.0/E   [30/1810Z]
  04        Tsu, Mie (WMO47651, Alt 3m)                 18.1/ESE [31/0320Z]
  05        Tamano, Okayama (JMA66501, Alt 2m)          18  /E   [31/1250Z]

  {Part VI}. Top-5 peak gust obs

  Ranking   Station                                     Peak wind (mps/dir)
  01        Murotomisaki, Kochi (WMO47899, Alt 185m)    60.9/ENE [31/0200Z]
  02        Hachijojima, Tokyo (WMO47678, Alt 79m)      44.6/ENE [29/0703Z]
  03        Shionomisaki, Wakayama (WMO47778, Alt 73m)  37.8/ENE [30/0812Z]
  04        Owase, Mie (WMO47663, Alt 15m)              36.8/E   [30/2344Z]
  05        Kure, Hiroshima (WMO47766, Alt 4m)          31.1/NNE [31/0902Z]

  {Part VII}. Top-5 SLP obs

  Ranking    Station                             Min SLP (hPa)
  01         Murotomisaki, Kochi (WMO47899)      983.3 [31/0237Z]
  02         Shimizu, Kochi (WMO47898)           989.2 [31/0555Z]
  03         Sukumo, Kochi (WMO47897)            989.9 [31/0647Z]
  04         Matsuyama, Ehime (WMO47887)         990.3 [31/0948Z]
  05         Kochi, Kochi (WMO47893)             990.5 [31/0431Z]

  {Part VIII} References (Japanese versions only)

  NOTE: "*" = record-breaking values for relevant stations.

  F. Addendum to July Tropical Cyclone Tracks File

     Following is the MSW comparison table prepared and sent by Huang
  Chunliang.  This was unavailable at the time the July tracks file was

  == Typhoon 13W/NAMTHEUN/0410 (JuL 24-Aug 3, 2004) ==

  TCWC       Storm ID                              PEAK MSW (kt)
  JTWC       Typhoon 13W (NAMTHEUN)                115
  JMA        Very Severe Typhoon 0410 (NAMTHEUN)    85
  NMCC       Typhoon 0410 (NAMTHEUN)               100
  HKO        Typhoon NAMTHEUN (0410)               ---*
  CWB        Moderate Typhoon 0410 (NAMTHEUN)      ---#
  Note 1 (*): HKO never issued any real-time warnings on this typhoon,
  which remained outside their AOR throughout its life.

  Note 2 (#): CWB data was insufficient for me when I was away in

  (Sections A-D written by Gary Padgett; Sections E & F compiled by Huang

                              TROPICAL STORM
                       (NMCC 0411 / NRL Invest 94W)
                               26 - 27 July

  A. Introduction

     Only NMC and GRMC, both sub-agencies of CMA (China Meteorological
  Administration), classified the system as a tropical storm in real time,
  while HKO, JMA, TMD and SMG (Macao) ranked it as a tropical depression
  only.  Another three TCWCs:  JTWC, CWB and PAGASA, however, just treated
  94W as a tropical disturbance/low-pressure area.   It should be noted
  that the last time there was a NMC tropical storm without a JMA number
  (i.e., JMA never regarded it as a tropical storm) was in mid-December,
  1999, when NMC issued several warnings on a SCS tropical storm (numbered
  TS-9917 by NMC and TD-33W by JTWC).

  B. Synoptic History

     Both NMC and GRMC initiated warnings on TD-03 at 26/0600 UTC.  And
  the MSW of 30 kts was kept for three warning cycles before two ships
  reported winds of gale force in the wee hours on the 27th (locally).
  So the depression was upgraded to Tropical Storm 0411 at 27/0000 UTC.
  It took only three hours for the unnamed storm, which turned out to be
  a short fuse, to make landfall.  According to the NMC and GRMC warnings,
  Tropical Storm 0411 made landfall in the coastal region between Huilai
  County and Lufeng City, Guangdong Province around 27/0305 UTC with a
  MSW of 40 kts and a CP of 995 hPa.  Once inland, the storm began to
  fade rapidly.  The cyclone was downgraded to a 25-kt depression at
  27/0600 UTC, at which time China issued their final warning.

  C. Meteorological Observations

  (1) Wind Observations

     The majority of the counties/cities of coastal southeastern Guangdong:
  Jieyang, Shantou and Shanwei Cities, as well as some counties/cities of
  Chaozhou City, reported sustained winds of Beaufort Force 6 to 8,
  gusting to Force 9 to 10 during the storm.  Significant gust reports

  Station Jiadong, Lufeng City (a sub-city of Shanwei City) - 52.7 kts
  Huilai Chuanqiao Reservoir (Huilai County, Jieyang City)  - 49.2 kts

  (2) Rainfall Observations

  (a) Guangdong Province

  [27/0000-28/0000 UTC]:  Rains >50 mm were recorded in 33 counties/cities,
  among which, Heping County, Fengshun County, Wengyuan County, Chaozhou
  City, Lianping County, Chao'an County, Shantou City and Chaoyang City
  reported rains >100 mm with Qingzhou, Heping County reporting the highest
  amount of 170.2 mm.

  [28/0000-29/0000 UTC]:  Rains >50 mm were recorded in 29 counties/cities,
  among which, Shanwei City, Sihui City, Zhongshan City, Fengkai County,
  Raoping County and Zhuhai City reported rains >100 mm with Nanlang,
  Zhongshan City reporting the highest amount of 182.6 mm.

  [29/0000-30/0000 UTC]:  Rains >50 mm were recorded in 28 counties/cities,
  among which, Huilai County, Maoming City, Puning City, Suixi County
  reported rains >100 mm with Maoming City reporting the highest amount of
  112.5 mm.

  (b) Fujian Province

  [27/0000-29/0000 UTC]: 3 stations (Yunxiao, Zhaoan & Dongshan) located in
  southern Fujian recorded rains >100 mm with Yunxiao County, Zhangzhou
  City reporting the highest amount of 116.6 mm.

  (c) Artificial Rain

     Artificial rainfall missions were selectively carried out in a few
  regions of both Guangdong and Fujian Provinces, where drought was relaxed
  to some extent thanks to the rains, whether artificial or not.

  D. Damage and Casualties

     In Nan'ao County, Shantou City, 11 fishermen were confirmed dead and
  another 11 were reported missing and feared dead after a fishing vessel
  capsized near Guangdong's Nanpeng Dao around the noon of July 27

     In Huilai County, Jieyang City, another fishing boat was bowled over
  by the stormy waves, leaving two fishermen missing in the evening of
  July 27 (locally).

     In Chao'an County, Chaozhou City, one person was killed when a tornado
  hit the county's Fengtang and Fuyang Towns around 27/1100 (BJT).  Another
  seven residents were injured when more than 100 houses in four villages
  were damaged or destroyed.  Preliminary statistics indicated that a total
  of 409 people from 93 families sustained damaged with 24 families home-
  less.  Direct economic losses were estimated at 11.2 million yuan.

     Damage to coastal dikes, water conservation facilities and farmlands
  was also reported in the Province.

  E. Addendum to July Tropical Cyclone Tracks File

     Following is the MSW comparison table prepared and sent by Huang
  Chunliang.  This was unavailable at the time the July tracks file was

  == Tropical Storm 94W/0411/TD03 (Jul 26-27, 2004) ==

  TCWC       Storm ID                              PEAK MSW (kt)
  JMA        Tropical Depression                   30
  NMCC       Tropical Storm 0411/TD03*             45
  HKO        Tropical Depression                   30
  TMD        Tropical Depression                   30

  Note 1: In the title line the storm grade was adopted based on the
  classification of the most "radical" TCWC.  Also, all the storm names/
  numbers available to me have been referenced.  In addition, the starting
  date points to the one when the system was initially upgraded to TD
  status by whatever TCWC, while the ending date represents the one when
  the storm was finally ranked as a TD by whatever TCWC.  (In this regard,
  NMCC was the TCWC that took the lead in upgrading the system to TD
  status on the 26th, while all the four agencies above issued their final
  TC bulletins at 27/0600 UTC.)

  Note 2 (*): The system was numbered "TD03" at 26/0600 UTC, when NMCC
  initiated their TC warnings.

  Note 3: Only NMC and GRMC, both sub-agencies of CMA (China Meteorological
  Administration), classified the system as a tropical storm in real time,
  while HKO, JMA, TMD and SMG (Macao) ranked it as a tropical depression
  only.   Another three TCWCs, JTWC, CWB & PAGASA, however, just treated
  94W as a tropical disturbance/low-pressure Area.

  (Report written by Huang Chunliang with slight editing by Gary Padgett)


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

  Activity for July:  No tropical cyclones


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

  Activity for July:  No tropical cyclones



  Activity for July:  No tropical cyclones



  Activity for July:  No tropical cyclones


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

  Activity for July:  No tropical cyclones


                              EXTRA FEATURE

     In order to shorten the amount of typing in preparing the narrative
  material, I have been in the habit of freely using abbreviations and
  acronyms.   I have tried to define most of these with the first usage
  in a given summary, but I may have missed one now and then.  Most of
  these are probably understood by a majority of readers but perhaps a
  few aren't clear to some.  To remedy this I developed a Glossary of
  Abbreviations and Acronyms which I first included in the July, 1998
  summary.  I don't normally include the Glossary in most months in
  order to help keep them from being too long.  If anyone would like to
  receive a copy of the Glossary, please e-mail me and I'll be happy
  to send them a copy.


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

    The track files are not being sent via e-mail.  They can be retrieved
  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, and
  Chris Landsea):>>>>

     Another website where much information about tropical cyclones may
  be found is the website for the UK Meteorological Office.  Their site
  contains a lot of statistical information about tropical cyclones
  globally on a monthly basis.  The URL is:>


     JTWC now has available on its website the complete Annual Tropical 
  Cyclone Report (ATCR) for 2003 (2002-2003 season for the Southern 
  Hemisphere).  ATCRs for earlier years are available also.

     The URL is:>

     Also, TPC/NHC has available on its webpage nice "technicolor"
  tracking charts for the 2003 Atlantic and Eastern North Pacific
  tropical cyclones; also, storm reports for all the 2003 Atlantic
  and Eastern North Pacific cyclones are now available, as well as
  track charts and reports on storms from earlier years.

     The URL is:>

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


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

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

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

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

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


Document: summ0407.htm
Updated: 17th May, 2005

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