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Monthly Global Tropical Cyclone Summary May 2006 [Summaries and Track Data] [Prepared by Gary Padgett] |
MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY
MAY, 2006
(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.)
IMPORTANT NOTE FROM THE AUTHOR -- PLEASE READ!!!
In order for the tropical cyclone summaries to continue with any
degree of timeliness, some changes are going to be necessary in order
to significantly reduce the amount of time required to prepare them. I
have many commitments and demands made upon my time, and to be honest,
I just do not have the enthusiasm I once had for writing them. I find
it increasingly difficult to spend hours poring over discussions and
warnings just to glean a few tidbits of information here and there to fit
into a historical narrative. However, so many persons have told me,
and continue to tell me, that they find the summaries and track files
useful, so I do not want to completely drop them. Some streamlining
of the narratives detailing the synoptic history of the storms will be
made for cyclones in all the basins, but there is going to be a
significant reduction in the coverage given to Atlantic and Northeast
Pacific tropical cyclones.
While these basins are personally my primary basins of interest (I
live less than 100 km from the Gulf of Mexico), I am reducing coverage
of these tropical cyclones for several reasons:
(1) A significant majority of the readers of these summaries live in the
United States, and Atlantic (and usually Eastern Pacific) storms are
given wide coverage on the Atlanta-based Weather Channel as well as
various other 24-hour TV cable news providers.
(2) Many persons outside the U. S. are also able to watch the cable news
channels and follow Atlantic cyclones in particular.
(3) Tropical cyclone warnings can be received via e-mail or downloaded
from websites from just about every warning agency in the world, and
any person interested in performing detailed research on any cyclone
can save these warnings for further study if they so desire. In
addition, TPC/NHC archives all their tropical cyclone advisories,
discussions and graphics on their website, and these are available
long-term for any person who desires to research a particular cyclone
in greater detail.
(4) In addition to the narrative summaries, from the beginning I have
prepared a tabular track file to accompany each month's summary.
These give a concise and quantitative history of each cyclone, and
in conjunction with the graphics which John Diebolt of Tucson is now
preparing based upon these track files, present a very adequate
numerical and pictorial representation of each cyclone's history.
(A picture is worth a thousand words!) Beginning with December,
2004, I have been including the link to each cyclone's track graphic
on John's website. (For more information on John's website, see
the Feature of the Month article in the February, 2005, summary.)
(5) I have discovered an online encyclopedia (Wikipedia) which contains
fairly detailed reports of tropical cyclones, especially for Atlantic
storms. I have included links to these reports already for several
storms and plan to continue doing so. I have recently been in
contact with one of the authors and managers of the Wikipedia
tropical cyclone project, and plans are for these reports to continue
to exist and grow in scope and remain available long-term.
(6) And finally, TPC/NHC has their extremely informative storm reports
available online beginning usually in late October (sometimes
earlier), and for the most part completed by the end of the calendar
year. Indeed, ever since the 2000 season the official NHC reports
have begun appearing before I could get the preliminary reports
completed for many of the latter cyclones each season, so I chose
instead to write just a brief article supplementing the official
reports for those cyclones.
I hope those who are primarily interested in Atlantic cyclones will
not be too disappointed, but this is a necessary step to insure that
reports on cyclones in other basins for which information is not so
readily available will not be running months behind, as has often been
the case in the past.
Also, Kevin Boyle and Simon Clarke have assured me that they are
still interested in writing tropical cyclone reports for the Western
North Pacific, Northeast Australia/Coral Sea and South Pacific basins,
so summaries for storms in those basins should continue with little
change.
*************************************************************************
MAY HIGHLIGHTS
--> Rare South China Sea super typhoon has adverse effects on several
southeastern Asian nations
--> First Eastern North Pacific tropical storm forms on schedule
*************************************************************************
ACTIVITY BY BASINS
ATLANTIC (ATL) - North Atlantic Ocean, Caribbean Sea, Gulf of Mexico
Activity for May: No tropical cyclones
*************************************************************************
NORTHEAST PACIFIC (NEP) - North Pacific Ocean East of Longitude 180
Activity for May: 1 tropical storm
Sources of Information
----------------------
Most of the information presented below was obtained from the
various tropical cyclone products issued by the Tropical Prediction
Center/National Hurricane Center (TPC/NHC) in Miami, Florida (or the
Central Pacific Hurricane Center (CPHC) in Honolulu, Hawaii, for
locations west of longitude 140W): discussions, public advisories,
forecast/advisories, tropical weather outlooks, special tropical
disturbance statements, etc. Some additional information may have
been gleaned from the monthly summaries prepared by the hurricane
specialists and available on TPC/NHC's website. All references to
sustained winds imply a 1-minute averaging period unless otherwise
noted.
Northeast Pacific Tropical Activity for May
-------------------------------------------
In recent years the tropical cyclone season in the Northeast Pacific
basin has begun almost like clockwork within the latter 10 days of May,
and 2006 was no exception. The first tropical depression (01E) formed
on 27 May and later that same day became Tropical Storm Aletta. Over
the period 1971-2005, the month of May has averaged about one storm
every other year, but 2006 was the seventh consecutive season in which
the first named storm has formed in May. By way of contrast, the 8-year
period 1992 through 1999 saw only one May tropical storm develop--an
unnamed storm in 1996. The only May in which two Eastern Pacific storms
developed was in 1984. Aletta produced 2.25 NSD--the average NSD for May
is 1.84 for the 35-year period. A short report on Aletta follows.
TROPICAL STORM ALETTA
(TC-01E)
27 - 30 May
-----------------------------------------
Most of the information in this short report was obtained from the
monthly summary for May prepared by the staff of TPC/NHC. Tropical
Storm Aletta represents the seventh consecutive year in which the
Eastern North Pacific tropical cyclone season has begun in the month of
May, a month which normally sees a tropical storm or hurricane form only
about every other year.
Aletta formed as a result of the interaction of a westward-moving
tropical wave with a low-level trough near the Gulf of Tehuantepec. The
resultant broad low-pressure area was located several hundred miles
south of Acapulco on 25 May. Organization gradually increased and the
system had developed into Tropical Depression 01E by early on the 27th,
centered about 165 nm southwest of Acapulco. The depression embarked on
a northerly track toward the Mexican coast and was upgraded to Tropical
Storm Aletta later that same day. Aletta's peak intensity of 40 kts was
attained at 0600 UTC on 28 May and was maintained for 36 hours. The
tropical cyclone moved erratically, executing a counterclockwise loop
southwest of Acapulco on the 28th. A strengthening ridge to the north
prevented a rendezvous with the Mexican coastline and Aletta began
drifting westward on the 29th while slowly weakening to a depression
by 30/0000 UTC. Aletta continued to weaken and dissipated about 170 nm
south-southeast of Manzanillo later on the 30th.
Aletta produced some locally heavy rains over portions of southern
Mexico with a 24-hour total of 91 mm in Oaxaca State. No damage nor
casualties were reported.
A graphic displaying the track of Tropical Storm Aletta may be found
at the following link:
The track in tabular form may be accessed at the following URL:
The link for the online Wikipedia report on Aletta is:
(Report written by Gary Padgett)
*************************************************************************
NORTHWEST PACIFIC (NWP) - North Pacific Ocean West of Longitude 180
Activity for May: 1 super typhoon
Sources of Information
----------------------
Most of the information presented below is based upon tropical
cyclone warnings and significant tropical weather outlooks issued
by the Joint Typhoon Warning Center of the U. S. Air Force and
Navy (JTWC), located at Pearl Harbor, Hawaii. In the companion
tropical cyclone tracks file, I normally annotate track coordinates
from some of the various Asian warning centers when their center
positions differ from JTWC's by usually 40-50 nm or more. All
references to sustained winds imply a 1-minute averaging period
unless otherwise noted.
Michael V. Padua of Naga City in the Philippines, owner of the
Typhoon 2000 website, normally sends me cyclone tracks based upon
warnings issued by the Japanese Meteorological Agency (JMA) and the
Philippines' Atmospheric, Geophysical & Astronomical Services
Administration (PAGASA). A very special thanks to Michael for the
assistance he so reliably provides.
In the title line for each storm I have referenced all the cyclone
names/numbers I have available: JTWC's depression number, the
JMA-assigned name (if any), JMA's tropical storm numeric designator,
and PAGASA's name for systems forming in or passing through their
area of warning responsibility.
SUPER TYPHOON CHANCHU
(TC-02W / TY 0601 / CALOY)
8 - 20 May
----------------------------------------------
Chanchu: contributed by the colony of Macau, is the Macanese word for
pearl
A. Introduction
---------------
The second significant tropical cyclone of 2006 in the NW Pacific
basin, Chanchu became the earliest system to be designated a super
typhoon by JTWC in the South China Sea. Super typhoons are a rarity in
that part of the world, and a search through the JTWC archives reveal
that the only other tropical cyclones to reach that intensity in the
South China Sea were Ryan (1995) and Sally (1996).
From its formation late on 8 May Chanchu crossed the Philippine
Archipelago on 11-12 May before peaking at 135 kts in the South China
Sea early on 15 May. After alarming the community of Hong Kong, China,
Chanchu veered sharply away towards the north and made landfall in
Guangdong Province in eastern China on 17 May.
B. Synoptic History
-------------------
Super Typhoon Chanchu began its life as a persistent area of
convection approximately 310 nm southeast of Yap. It was first noted in
JTWC's STWO issued at 2030 UTC 5 May. The tropical disturbance remained
a weak, poorly-organized feature until 7 May when the system's
organization began to improve and the LLCC began to consolidate. A TCFA
was issued at 08/1100 UTC, relocating the disturbance to a position
approximately 100 nm west-southwest of Yap. The first warning on
Tropical Depression 02W was issued at 08/1800 UTC with the system at this
time passing north of Palau. TD-02W was upgraded to a 35-kt tropical
storm at 09/0000 UTC, and acquired the name Chanchu at 09/1200 UTC when
JMA raised their 10-min avg MSW to 35 kts.
Tropical Storm Chanchu continued to intensify as it tracked
predominantly west-northwestward along the southern periphery of a
subtropical ridge. It was upgraded to a 75-kt typhoon at 1800 UTC
10 May while centred approximately 440 nm east-northeast of Zamboanga,
Philippines. Typhoon Chanchu weakened slightly as it crossed the
northern tip of Samar, Philippines, on 11 May. However, despite the
hindering effects of land, Chanchu re-strengthened while over the
Sibuyan Sea on 12 May. The storm's intensity fluctuated as it tracked
erratically westward across the Philippine island of Mindoro, emerging
into the South China Sea early on 13 May where it slowly began to
reorganize. The tropical cyclone was forecast in the long-term to
become very intense and to make landfall in the vicinity of Hong Kong,
China.
Drifting westwards, Typhoon Chanchu underwent rapid intensification
over the South China Sea on 14 May. It was upgraded to a super typhoon
at 1800 UTC 14 May while located approximately 515 nm south of Hong
Kong, China, before peaking at 135 kts six hours later. Chanchu
abruptly veered north on 15 May as the subtropical ridge split apart,
and this northward path into the resulting weakness took the storm into
a less favourable environment. At 15/0600 UTC Chanchu was downgraded
back to typhoon intensity. The tropical cyclone gradually weakened
further but remained a powerful system for the next two days while
moving on a north to north-northeasterly trajectory through the South
China Sea towards the Chinese coast, away from Hong Kong. The
typhoon made landfall near Shantou, Guangdong Province, late on 17 May
with the MSW estimated at 75 kts. Chanchu continued up the eastern
coastal region of China and was downgraded to a 45-kt tropical storm on
JTWC's final warning at 18/0000 UTC. JMA also downgraded Chanchu to a
tropical storm at this time but continued to issue bulletins until it
was declared extratropical over the East China Sea at 19/0000 UTC. The
weak residual LOW continued northeastward, passing over the Japanese
islands of Kyushu, Shikoku and Honshu, eventually exiting into the
North Pacific near Tokyo.
The highest MSW estimated by JMA was 90 kts with a minimum CP of
930 mb. PAGASA estimated a peak intensity of 80 kts while Typhoon
Chanchu/Caloy was within their AOR. PAGASA first assigned the name
Caloy at 09/0000 UTC after the system had crossed 135E.
A graphic displaying the track of Super Typhoon Chanchu/Caloy may be
found at the following link:
The track in a tabular format may be accessed at the following URL:
C. Damage and Casualties
------------------------
Typhoon Chanchu was responsible for 41 deaths in the Philippines,
including 21 persons who perished when a motor boat capsized off
Masbate Island. In China, at least twenty-five people were reported
dead with four missing. Eleven fishing vessels from Vietnam were sunk,
killing 44 fishermen, and at least 190 Vietnamese were reported
missing. The above casualty information, along with a much more
detailed description on the impact of Super Typhoon Chanchu, may be
obtained at the following link:
(Report written by Kevin Boyle)
*************************************************************************
NORTH INDIAN OCEAN (NIO) - Bay of Bengal and Arabian Sea
Activity for May: No tropical cyclones
*************************************************************************
SOUTHWEST INDIAN OCEAN (SWI) - South Indian Ocean West of Longitude 90E
Activity for May: No tropical cyclones
*************************************************************************
NORTHWEST AUSTRALIA/SOUTHEAST INDIAN OCEAN (AUW) - From 90E to 135E
Activity for May: No tropical cyclones
*************************************************************************
NORTHEAST AUSTRALIA/CORAL SEA (AUE) - From 135E to 160E
Activity for May: No tropical cyclones
*************************************************************************
SOUTH PACIFIC (SPA) - South Pacific Ocean East of Longitude 160E
Activity for May: No tropical cyclones
*************************************************************************
SPECIAL FEATURE - SOURCES OF TROPICAL CYCLONE INFORMATION
The purpose of this section is to list some websites where many and
varied types of tropical cyclone information are archived. Many readers
will know about these already, but for the benefit of those who don't,
I wanted to include them.
(1) Aircraft Reconnaissance Information
---------------------------------------
Various types of messages from reconnaissance aircraft may be
retrieved from the following FTP site:
Information regarding how to interpret the coded reconnaissance
messages may be found at the following URL:
Links are also included to websites with further information about the
U. S. Air Force 53rd Weather Reconnaissance Squadron and the NOAA Air-
craft Operations Center.
(2) Archived Advisories
-----------------------
All the advisory products (public advisories, forecast/advisories,
strike probabilities, discussions, various graphics) issued by TPC/NHC
are archived on TPC's website. For the current year (using 2004 as an
example), the archived products can be found at:
Links to tropical products archives for earlier years are available at
the following URL:
JTWC warnings for past storms are archived on the NRL Monterry website:
On the NRL site, the link to past years can be found in the upper left
corner of the screen.
I am not aware at the moment of any other TCWC which archives all
its tropical cyclone warning/advisory products for public access, but
if I learn of any, I will add them to this list.
(3) Satellite Imagery
---------------------
Satellite images of tropical cyclones in various sensor bands are
available on the NRL Monterrey and University of Wisconsin websites,
courtesy of Jeff Hawkins and Chris Velden and their associates. The
links are:
On the NRL site, the link to past years can be found in the upper left
corner of the screen. For the CIMSS site, a link to data archives is
located in the lower left portion of the screen.
Additional tropical satellite imagery, along with looping ability for
composite microwave imagery for the Western Hemisphere north of the
equator, can be found at:
(1) For the Eastern North Pacific:
(2) For the Atlantic, Gulf of Mexico and Caribbean Sea:
I'm sure there are other sites with available imagery available, and
as I learn of them, I will add the links to this list.
*************************************************************************
EXTRA FEATURE
In order to shorten the amount of typing in preparing the narrative
material, I have been in the habit of freely using abbreviations and
acronyms. I have tried to define most of these with the first usage
in a given summary, but I may have missed one now and then. Most of
these are probably understood by a majority of readers but perhaps a
few aren't clear to some. To remedy this I developed a Glossary of
Abbreviations and Acronyms which I first included in the August, 1998
summary. I don't normally include the Glossary in most months in
order to help keep them from being too long. If anyone would like to
receive a copy of the Glossary, please e-mail me and I'll be happy
to send them a copy.
*************************************************************************
AUTHOR'S NOTE: This summary should be considered a very preliminary
overview of the tropical cyclones that occur in each month. The cyclone
tracks (provided separately) will generally be based upon operational
warnings issued by the various tropical cyclone warning centers. The
information contained therein may differ somewhat from the tracking and
intensity information obtained from a "best-track" file which is based
on a detailed post-seasonal analysis of all available data. Information
on where to find official "best-track" files from the various warning
centers will be passed along from time to time.
The track files are not being sent via e-mail. They can be retrieved
from the archive sites listed below. (Note: I do have a limited e-mail
distribution list for the track files. If anyone wishes to receive
these via e-mail, please send me a message.)
Both the summaries and the track files are standard text files
created in DOS editor. Download to disk and use a viewer such as
Notepad or DOS editor to view the files.
The first summary in this series covered the month of October,
1997. Back issues can be obtained from the following websites
(courtesy of Michael Bath, Michael V. Padua, Michael Pitt, Chris
Landsea, and John Diebolt):
Another website where much information about tropical cyclones may
be found is the website for the UK Meteorological Office. Their site
contains a lot of statistical information about tropical cyclones
globally on a monthly basis. The URL is:
TROPICAL CYCLONE REPORTS AVAILABLE
JTWC now has available on its website the Annual Tropical Cyclone
Report (ATCR) for 2004 (2003-2004 season for the Southern Hemisphere).
ATCRs for earlier years are available also.
The URL is:
Also, TPC/NHC has available on its webpage nice "technicolor"
tracking charts for the 2004 Atlantic and Eastern North Pacific
tropical cyclones; also, storm reports for all the 2004 Atlantic
and Eastern North Pacific cyclones are now available, as well as
track charts and reports on storms from earlier years.
The URL is:
A special thanks to Michael Bath of McLeans Ridges, New South Wales,
Australia, for assisting me with proofreading the summaries.
PREPARED BY
Gary Padgett
E-mail: [email protected]
Phone: 334-222-5327
Kevin Boyle (Eastern Atlantic, Western Northwest Pacific, South
China Sea)
E-mail: [email protected]
Simon Clarke (Northeast Australia/Coral Sea, South Pacific)
E-mail: [email protected]
*************************************************************************
*************************************************************************
|
Document: summ0605.htm
Updated: 8th August 2006 |
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