MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY
AUGUST, 2006
Second Installment
SPECIAL NOTE: The August summary is being issued in three installments.
The first one covered the Atlantic basin and contained an extra feature.
This second installment covers the Northeast Pacific basin while the
third will cover the Northwest Pacific and North Indian Ocean basins.
(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.)
NOTE FROM THE AUTHOR: Almost two years ago I began including links to
track graphics prepared by John Diebolt of Tucson, Arizona, and archived
on his tropical cyclone website. A few months back John experienced a
disk crash which resulted in a error. He had to request assistance from
the programmer who had written the map-generation software, but so far
has not been able to get the problem solved. As a convenience to users,
I've also recently been including links to the individual tabular tracks,
prepared by myself, which John had archived on his website. Now, due to
family issues, John has not had time to place the tracks for the August
cyclones on the website. I have checked the websites listed at the end
of the summaries and found that the entire August track file has been
archived on two of them. The links are:
http://australiasevereweather.com/cyclones/2007/trak0608.htm
http://www.typhoon2000.ph/garyp_mgtcs/aug06tks.txt
*************************************************************************
AUGUST HIGHLIGHTS
--> Atlantic rather quiet--tropical storm affects Haiti, Cuba, Florida
and U. S. Eastern Seaboard
--> Eastern North Pacific very active--one hurricane adversely affects
the Baja California Peninsula
--> Extremely long-lived Central and Western Pacific major hurricane/
super typhoon strikes both Johnston and Wake Islands
--> Western North Pacific very active--China experiences very rare
strike by a destructive super typhoon
--> Several weak depressions in Bay of Bengal
*************************************************************************
ACTIVITY BY BASINS
ATLANTIC (ATL) - North Atlantic Ocean, Caribbean Sea, Gulf of Mexico
Activity for August: 2 tropical storms
1 hurricane
NOTE!!! The Atlantic basin was covered in the first installment of the
August summary.
*************************************************************************
NORTHEAST PACIFIC (NEP) - North Pacific Ocean East of Longitude 180
Activity for August: 2 tropical storms
2 hurricanes
3 major hurricanes **
** - one of these formed in Central North Pacific and became a Western
Pacific super typhoon
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.
For the portion of Hurricane/Typhoon Ioke's track lying west of
longitude 180 the following applies:
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.
Northeast Pacific Tropical Activity for August
----------------------------------------------
Following are some statistics for the Northeast Pacific basin during
the month of August:
August Average
Parameter 2006 1971 - 2005
--------------------------------------------------------
Named Storms (NS) 7 4.0
Hurricanes (H) 5 2.3
Intense Hurricanes (IH) 3 1.1
Named Storm Days (NSD) 27.00 19.9
Hurricane Days (HD) 16.00 8.0
Intense Hurricane Days (IHD) 7.25 1.7
As can be seen, the month of August, 2006, was far above average in
all categories. The overall net tropical cyclone activity (utilizing
all six parameters) was a whopping 238% of the amount of tropical cyclone
activity normally seen in August. By way of contrast, the Atlantic
basin was well below normal in August, 2006, with the net activity for
that basin only about half the average level. The month was the most
active August in the Northeast Pacific basin since 2002 when five NS
developed with three becoming intense hurricanes. Similarly to Hurricane
Ioke of 2006, Hurricane Ele of 2002 formed in the Central North Pacific,
reached major hurricane intensity and entered the Northwest Pacific
basin as an intense typhoon. Unlike Ioke, however, Ele did not reach
Category 5 intensity.
Tropical Storms Fabio and Gilma were both short-lived weak tropical
cyclones at the beginning of the month. Hurricane Hector formed around
mid-month well southwest of Mexico and moved almost to 140W before
dissipating, becoming a Category 2 hurricane along the way. Hurricane
Ileana formed late in the 3rd week of August at the same time that Ioke
was forming in the Central Pacific. Ileana became a Category 3 hurricane
but remained well off the Mexican coast. Hurricane John formed near the
end of the month just off the coast and became a Category 4 hurricane,
later weakening to Category 2 status just before striking the south-
eastern portion of the Baja California Peninsula. Hurricane Kristy
formed farther west while John was operating near the coast of Mexico
and went through several intensity fluctuations while gradually
weakening. Reports follow on all seven of the named cyclones.
The online Wikipedia reports for the Eastern Pacific cyclones may
be accessed at the following URL:
http://en.wikipedia.org/wiki/2006_Pacific_hurricane_season
More expanded reports are available for Hurricane John and Hurricane/
Typhoon Ioke. The links are included in the individual reports for
those cyclones.
TROPICAL STORM FABIO
(TC-07E)
31 July - 3 August
----------------------------------------
Tropical Storm Fabio formed from a tropical wave which had emerged
from the coast of Africa on 15 July. The wave marched steadily across
the tropical Atlantic and Caribbean and crossed Central America into the
Eastern Pacific on 23 July. Convection began to increase along the
wave during the following days and a weak low pressure area had formed
by 28 July about 500 nm southwest of Manzanillo, Mexico. Over the next
three days the LOW moved northwestward, slowly becoming better organized.
By 31 July the system had acquired enough deep convection to be
designated as a tropical depression, and advisories were initiated on
Tropical Depression 07E at 2100 UTC. The center of TD-07E was then
located approximately 850 nm southwest of Cabo San Lucas on the southern
tip of the Baja California Peninsula. Six hours later the depression was
upgraded to Tropical Storm Fabio based on a consensus of satellite
intensity estimates of 35 kts or higher.
Throughout its life Fabio moved westward under the influence of a
mid-tropospheric ridge to the north and reached its estimated peak
intensity of 45 kts around 1200 UTC on 1 August while located about
1000 nm west-southwest of Cabo San Lucas. Fabio retained its peak
intensity for about 24 hours, then weakening set in due to the influence
of increasing vertical shear and a more stable air mass. The tropical
storm was downgraded to a depression at 03/0300 UTC when centered about
1400 nm west-southwest of the Cabo, and the final TPC/NHC advisory
at 03/2100 UTC placed the weakening depression about 975 nm east-
southeast of Hilo, Hawaii. The residual remnant LOW continued westward
and had degenerated into an open wave by 6 August.
No damage or casualties were attributed to Tropical Storm Fabio.
(Report written by Gary Padgett)
TROPICAL STORM GILMA
(TC-08E)
1 - 3 August
----------------------------------------
The precursor of Tropical Storm Gilma was a tropical wave which had
exited the coast of Africa on 17 July and had entered the Eastern Pacific
on the 25th. Convection began to increase on the 29th and by 01/0000 UTC
the system had acquired enough deep convection and sufficient
organization to be classified as a tropical depression. The first
advisory on Tropical Depression 08E was issued at 0300 UTC on 1 August
with the center about 400 nm south of Manzanillo, Mexico. In spite of
moderate easterly shear, the depression strengthened into a minimal
tropical storm later that day about 335 nm south-southwest of Manzanillo.
Gilma embarked on a generally west-northwesterly track roughly
parallel to the Mexican coastline. The persistent easterly shear,
however, hampered intensification and Gilma never intensified beyond
minimal tropical storm intensity of 35 kts, and was classified as a
tropical storm for only 18 hours. By early on 2 August the LLCC had
become completely exposed and Gilma was downgraded to depression status
at 02/0900 UTC. The depression continued moving slowly to the west-
northwest and slowly weakened. The final TPC/NHC advisory on Gilma,
issued at 2100 UTC on 3 August, placed only a weak 20-kt center about
425 nm south of Cabo San Lucas. The remnant LOW continued in the same
general direction and dissipated on the 5th about 325 nm south-southwest
of the Cabo.
No damage or casualties were attributed to Tropical Storm Gilma.
(Report written by Gary Padgett)
HURRICANE HECTOR
(TC-09E)
15 - 23 August
------------------------------------
Like its two predecessors, Hurricane Hector developed from a tropical
wave which had its origins in Africa. Hector's parent wave emerged from
the African coast on 31 July and reached the Eastern Pacific on the 10th
of August. Shower activity gradually increased as the system passed to
the south of the Gulf of Tehuantepec, and a broad low pressure area
developed about 425 nm south of Acapulco on 13 August. Convection
gradually became better organized and advisories were begun on Tropical
Depression 09E at 2100 UTC on 15 August with the system centered about
650 nm south-southwest of Cabo San Lucas. Within 12 hours Tropical Storm
Hector was christened and continued to intensify steadily, being upgraded
to a 75-kt hurricane at 1500 UTC on 17 August while located approximately
800 nm southwest of Cabo San Lucas. The upgrade was based on Dvorak
intensity estimates of 77 kts and 65 kts from TAFB and SAB, respectively.
Also, current AODT intensity estimates suggested that Hector was slightly
stronger than 70 kts.
Hurricane Hector continued moving west-northwestward along the south-
western periphery of a deep layer ridge extending over the Eastern
Pacific from the southwestern United States. The cyclone reached its
peak estimated intensity of 90 kts at 0900 UTC on the 18th while centered
about 900 nm west-southwest of the southern tip of the Baja California
Peninsula. The MSW was subsequently lowered slightly to 85 kts, but
was upped to 90 kts once more at 19/0900 UTC. By the 20th Hector was
entering a region of cooler SSTs and began to slowly weaken. The
cyclone was downgraded to a 60-kt tropical storm at 20/1500 UTC while
located approximately 1300 nm west-southwest of Cabo San Lucas, and
18 hours later had become a minimal tropical storm. On the 22nd Hector
turned to more of a westerly track and lost most of its deep convection,
weakening to a depression around 23/0000 UTC. The final TPC/NHC
advisory on Hector was issued at 23/0300 UTC and placed the weakening
cyclone roughly 1000 nm east-northeast of Hilo, Hawaii. The residual
LOW continued drifting westward and dissipated on the 24th.
No damage or casualties have been attributed to Hurricane Hector.
(Report written by Gary Padgett)
HURRICANE/SUPER TYPHOON IOKE
(TC-01C / TY 0612)
20 August - 7 September
------------------------------------------------
A. Introduction
---------------
Long-lived Hurricane/Typhoon Ioke was truly one of the most remarkable
tropical cyclones in many years. Forming in the Central North Pacific
to the south of Hawaii--a region where tropical cyclones are rather rare
events--the storm reached an intensity in that region only very rarely
seen, and maintained itself as a very intense tropical cyclone for well
over a week as it trekked from deep in the tropical Central Pacific to
recurvature a few hundred miles east of Japan. Along the way it
managed to make very close approaches to Johnston and Wake Islands--two
isolated outposts in the vast reaches of the Central and Western Pacific.
Following are a few statistics regarding Ioke's intensity:
(1) Consecutive days as a Category 3 or higher hurricane: 10.25
(2) Total days as a Category 3 or higher hurricane: 11.25
(3) Consecutive days as a Category 4 or higher hurricane: 8.50
(4) Total days as a Category 4 or higher hurricane: 9.00
(5) Consecutive days as a super hurricane/typhoon: 7.25
(6) Consecutive days as a super typhoon west of Dateline: 5.00
(7) Total days as a Category 5 hurricane/typhoon: 3.00
Ioke set several new records for intense tropical cyclone longevity.
The great cyclone was at Category 4 intensity for 9.00 days, besting
the previous record of 8.25 days set by Atlantic Hurricane Ivan in
2004. Also, Ioke was a Category 4 cyclone for 34 consecutive 6-hourly
synoptic periods, exceeding Ivan's record of 32 consecutive reporting
periods as a Category 4 hurricane. The previous Pacific record-holder
for Category 4 longevity was Typhoon Paka of 1997--a Category 4 or
higher storm for 6.75 days and consecutively for 6.25 days.
With regard to super typhoon intensity (MSW >= 130 kts), Ioke's reign
of 7.25 days greatly exceeds the 5.00 days of Super Typhoon Fengshen
in 2002 and 4.75 days set by Super Typhoon Joan in 1997--the previous
record holders. However, part of Ioke's life at 130 kts or higher was
east of the Dateline. West of the Dateline, Ioke was a super typhoon
for twenty 6-hourly synoptic periods--equaling Fengshen.
One final record--the estimated minimum CP of 920 mb for Ioke while
still east of the Dateline is likely to be the lowest CP on record for
a Central Pacific cyclone. An operational pressure of 910 mb was
assigned for 1994's Hurricane John, but according to Andy Nash of the
CPHC, the lowest CP for that hurricane in the new, revised Central
North Pacific Best Tracks file, due to be released in the near future,
will be 929 mb--the lowest reported by reconnaissance aircraft flying
into Hurricane John.
B. Synoptic History
-------------------
(1) Storm Origins
-----------------
The disturbance from which Ioke developed can be traced back to at
least 16 August. A Tropical Weather Outlook issued by CPHC at 2000 UTC
noted that an area of disturbed weather was located about 800 nm south-
east of Hilo and moving toward the west at around 13 kts. A recent Quik-
Scat pass had not indicated any evidence of a LLCC--only an east/west-
oriented trough. The disturbance continued westward and by the morning
of the 19th was located about 600 nm south-southwest of Hilo and had
shown some signs of increasing organization. By late afternoon (local
time) the system's organization had increased to the point that
advisories were initiated on Tropical Depression 01C at 20/0300 UTC.
The depression was then centered about 675 nm south of Honolulu and was
moving westward at 10 kts.
Only six hours later TD-01C had been upgraded to Tropical Storm Ioke,
the first named storm to develop in the Central North Pacific since
Hurricane Huko in October, 2002. The years 2003, 2004 and 2005 had all
produced a tropical depression numbered 01C, but in all cases the system
had only lasted for a day or so, being unable to escape the ITCZ and
eventually being overwhelmed by ITCZ convection. The upgrade to
tropical storm status was based upon Dvorak ratings of T2.5 from CPHC,
JTWC and AFWA. Also, a QuikScat pass had shown some 35-kt vectors with
even a few up to 40 kts. Incidentally, the name Ioke is a
transliteration of the name Joyce into the rather limited Hawaiian
alphabet and phonetic system.
(2) Birth to Johnston Island
----------------------------
The initial forecast upgrading Ioke to tropical storm status called
for the cyclone to attain hurricane intensity in 24 hours, and that is
what happened. During the afternoon of the 20th the system began to
intensify very rapidly with an eye appearing, so Ioke was upgraded to
a hurricane at 0300 UTC on 21 August while located about 685 nm south-
southwest of Honolulu. The cyclone at the time was moving toward the
west-northwest at around 13 kts. Ioke's intensification did not stop
after it became a hurricane. Only eighteen hours after being upgraded
the cyclone had intensified into a 100-kt Category 3 hurricane on the
Saffir/Simpson scale. Dvorak estimates were ranging from 90 to 102 kts
and the most recent AODT estimate was 110 kts. Major Hurricane Ioke was
by this time moving northwestward along the southwestern periphery of a
weak subtropical ridge and southeast of a deepening trough in the middle
and upper levels. The storm was becoming a threat to small Johnston
Island and a hurricane warning was issued at 21/2100 UTC for the atoll,
even though there are no longer any permanent residents.
Ioke continued to intensify and at 22/0300 UTC was upgraded to a
Category 4 hurricane with the MSW estimated at 115 kts, based on Dvorak
ratings of T5.5 and T6.0. The cyclone at this time was located about
200 nm southeast of Johnston Island and moving toward the island at
11 kts. By 22/1500 UTC Ioke was showing the first signs of weakening by
losing its warm center, the result of some westerly shearing at high
levels. The MSW was lowered to 90 kts at 1800 UTC with the hurricane's
center then located about 40 nm south-southeast of Johnston Island. By
2100 UTC the eye had become ill-defined and a water vapor loop showed
that the moisture field on the west side of the hurricane had eroded
some. Visible and infrared imagery showed a remnant northern eyewall
still likely intact about 10 miles south of Johnston. By 23/0000 UTC
the center of Ioke had slipped by to the south of the island and was
located about 25 nm to the south-southwest. Six hours later the storm
was about 35 nm to the west of the island, still moving northwestward
at 8 kts and maintaining an intensity of 90 kts. (Impacts to Johnston
Island will be discussed in Section D below.)
(3) Johnston Island to Dateline
-------------------------------
Hurricane Ioke maintained its 90-kt intensity through the remainder
of 23 August as it plodded slowly northwestward away from Johnston Atoll.
Two things happened on the 24th: the storm began to move on a west-
northwesterly track, and it began to intensify once again. By 24/0600
UTC Ioke had reached Category 3 status once more with a MSW of 100 kts,
and 12 hours later the winds were upped to 125 kts, making Ioke a
Category 4 hurricane once more. Visible pictures showed a symmetric
hurricane with a 20-nm eye and with deep convection wrapping completely
around the eye. Satellite intensity estimates were 127 kts from CPHC,
AFWA, JTWC and SAB. Hurricane Ioke was forecast to maintain intensity
for 36 hours, followed by slow weakening. One model, however, called
for the storm to reach Category 5 status after 48 hours. This model
had it right, only it was a little slow. Only 12 hours after being
re-upgraded to Category 4 status, Ioke was a Category 5 hurricane with
peak winds estimated at 140 kts, based on Dvorak ratings T6.5 and T7.0.
The hurricane at this time was centered about 315 nm west-northwest of
Johnston Island, far removed from any other islands.
As an anticyclone aloft began to build north of the hurricane, Ioke's
track became westerly. The 25/1500 UTC discussion from CPHC noted that
several hours earlier the well-developed and very warm eye had cooled
and the very cold surrounding cloud tops had warmed and become elongated,
but subsequently the cloud tops had cooled and become more symmetrical
and the eye had warmed once more. This fluctuation was attributed to
an eyewall replacement cycle as well as some shear. In spite of this,
Ioke's MSW remained at 140 kts. The hurricane weakened below Category 5
status for 12 hours beginning at 26/0000 UTC as winds dropped to 130 kts,
but the MSW was bumped back to 140 kts at 1200 UTC. This fluctuation in
intensity was also attributed to an eyewall replacement cycle. Hurricane
Ioke was the 5th Category 5 hurricane on record in the Central North
Pacific, and the first to form and achieve this distinction in that
region. Hurricanes Emilia, Gilma and John of 1994 all moved in from
the Eastern Pacific, and Typhoon Patsy of 1959 came from the Western
Pacific.
The cyclone was by this time tracking to the west-southwest as
pressures to the north increased. Ioke was south of a huge anticyclone
in the mid-Pacific which was flanked by anomalously strong mid and upper-
level cyclones near 150W and 155E. This configuration resulted in low
shear and a favorable outflow pattern, and in conjunction with warm SSTs,
set the stage for Ioke to maintain itself as a very intense cyclone for
many more days. The west-southwesterly motion continued and the intense
Hurricane Ioke reached the International Dateline on 27 August still at
Category 5 intensity. CPHC issued their final advisory on Ioke at
27/0300 UTC with JTWC and JMA assuming responsibility for the 27/0600 UTC
warnings. The first JTWC warning placed the center of Ioke about 785 nm
east of Wake Island, or about 675 nm south-southwest of Midway Island.
Typhoon-force winds extended outward 55-60 nm from the center with gales
covering a zone about 300 nm in diameter.
(4) Dateline to Wake Island
---------------------------
The west-southwesterly motion continued through 0000 UTC on 29 August
when Ioke "bottomed out" in latitude near 16.0N/174.2E. The storm had
re-attained Category 5 status at 26/1200 UTC and a MSW of 140 kts was
maintained for 36 hours. The intensity was lowered to 135 kts at 0000
UTC on the 28th and further to 130 kts six hours later, but Ioke remained
at or above super typhoon intensity (130 kts) through this period.
Increased upper-level inflow from a ridge to the northwest was blamed
for the slight weakening trend. Super Typhoon Ioke was upgraded back
to 140 kts at 29/1800 UTC while centered approximately 340 nm east-
southeast of Wake Island. The west-northwesterly motion had resumed
and Ioke was making a beeline for the tiny island. Even before the
storm had reached the Dateline some of the models were hinting that
Wake Island might eventually lie in its path.
Ioke's final stint as a Category 5 typhoon lasted for 18 hours and
the intensity was brought down slightly to 135 kts at 30/1200 UTC, but
the storm remained a formidable super typhoon as it closed in on small
Wake Island. At 31/0000 UTC Ioke's center was about 110 nm east-
southeast of the island, and by 0600 UTC had closed to about 45 nm to
the east. However, the track had turned more to the northwest (at
10 kts) and this slight turn kept the center of the eye just to the
north of Wake Island. At 31/1200 UTC the center had moved to a point
30 nm northwest of the island, and this distance had increased to 90 nm
by 1800 UTC. Ioke's estimated MSW remained at 135 kts during its close
approach to Wake Island. (Impacts to Wake Island will be discussed in
Section D below.)
(5) Wake Island to Alaska
-------------------------
Ioke was not to remain a super typhoon for much longer after passing
Wake Island. By 1200 UTC on 1 September the eye had become cloud-filled
and oblong in shape. Entrainment of drier mid-level air along with an
increase in vertical shear were responsible for the weakening. The
MSW was lowered from 130 kts to 115 kts in the 1200 UTC warning, but
held steady there for another 18 hours, followed by very slow weakening.
The cyclone continued moving on a west-northwest to northwesterly track
in the general direction of Japan. By 3 September Ioke was moving to
the north-northwest from a position about 820 nm southeast of Tokyo.
The weakening process began to accelerate on the 3rd with Ioke's MSW
dropping from 100 kts at 03/0600 UTC to minimal typhoon intensity of
65 kts at 04/1200 UTC. As is often the case with typhoons beginning to
undergo extratropical transition, JMA's 10-min avg MSW estimates were
higher than the 1-min avg values reported in JTWC's warnings.
JTWC downgraded Ioke to a 60-kt tropical storm at 05/0000 UTC with
the system moving northward at 17 kts. JMA, however, maintained Ioke
at typhoon intensity for another 24 hours. At 0600 UTC the center of
Ioke passed about 375 nm due east of Tokyo. Six hours later JTWC
issued their final warning on the storm, which was by now tracking
northeastward at 23 kts ahead of an approaching trough. In JTWC's
estimation Ioke was beginning to transition into an extratropical
cyclone, but JMA continued to classify Ioke as a tropical cyclone until
0000 UTC on the 7th when it was in the Bering Sea barreling northeastward
at 45 kts. By 07/1200 UTC the former super typhoon's remnants had
crossed the Dateline and were dropped from JMA's marine warnings. Based
on information found in the online Wikipedia report (see Section D
below), Ioke's remnants continued eastward and apparently moved over
portions of Alaska.
C. Meteorological Observations
------------------------------
Around 0300 UTC on 31 August the center of Super Typhoon Ioke passed
over buoy 52609, apparently located a short distance east of Wake Island.
This buoy does not report wind speed, but reported a minimum SLP of
921.5 mb as the eye passed directly over the buoy. An anemometer on
Wake Island reported sustained winds of 68 kts, gusting to 87 kts, at
31/0618 UTC, but the instrument ceased reporting after this time. A
barometer on the island reported a SLP of 934 mb at 31/0906 UTC.
D. Damage and Casualties
------------------------
On Johnston Atoll, twelve (some accounts say 13) persons aboard a
U. S. Air Force vessel safely rode out the storm in a hurricane-proof
bunker on the island. Five of the 12 were crew members, and the other
seven were contractors hired by the Air Force to perform repair work on
the island. Johnston Island was formerly a U. S. military outpost, but
is now a wildlife refuge and normally uninhabited most of the time. A
fly-over of the island the next day revealed surprisingly little damage.
The few trees on the island were still standing and flocks of adult birds
were seen flying around.
As it became apparent that Super Typhoon Ioke would pose a serious
threat to Wake Island, the island's 188 residents were evacuated by
air to Hawaii. A reconnaissance mission flown over Wake Island by the
U. S. Coast Guard after Ioke had passed revealed blown-off roofs and
downed trees--in general, overall moderate damage, but considered
repairable.
JMA issued evacuation orders for its staff on the Japanese island of
Minami Torishima with the approach of the typhoon on 1 September, but
no damage has been reported.
And finally, the extratropical remnants of Ioke produced 7.6-meter
waves and a severe storm surge along the western Alaskan coastline,
resulting in severe beach erosion. The former typhoon produced heavy
rainfall and 25 to 35-kt winds over the state on 7 September. Rainfall
totaled 29.2 mm in Bethel and contributed to above normal rainfall totals
for the month of September in Juneau.
Some of the above information (especially the final paragraph) was
gleaned from the Wikipedia report on Ioke, which also has many links to
sites where additional information may be obtained. The URL is:
http://en.wikipedia.org/wiki/Hurricane_Ioke
(Report written by Gary Padgett)
HURRICANE ILEANA
(TC-10E)
21 - 27 August
------------------------------------
Sometime around mid-August a tropical wave emerged into the Eastern
Pacific and gradually began to show signs of development. By 1200 UTC
on 21 August convection had become organized sufficiently to be
classified as a tropical depression and warnings were initiated on
Tropical Depression 10E at 1500 UTC. The depression was then located
about 300 nm south-southwest of Acapulco. The new depression quickly
strengthened and was upgraded to Tropical Storm Ileana at 2100 UTC.
Ileana embarked on a remarkably straight west-northwest to northwesterly
track which it followed throughout its lifetime. Strengthening
continued and Ileana reached hurricane intensity around 1800 UTC on
22 August while centered approximately 300 nm southwest of Manzanillo,
Mexico. The storm intensified rapidly, reaching Category 3 status
on the Saffir/Simpson scale at 23/0600 UTC and peaking at 105 kts six
hours later while centered about 325 nm south-southwest of Cabo San
Lucas.
Following its peak intensity Ileana continued on its northwesterly
course and gradually began to weaken. Ileana's initial weakening was
in part due to an eyewall replacement cycle, but the storm was prevented
from re-intensifying due to movement over increasingly cooler waters.
The hurricane was downgraded to a 55-kt tropical storm at 0900 UTC on
26 August while located approximately 450 nm west of Cabo San Lucas,
and was further downgraded to a tropical depression 24 hours later.
The final TPC/NHC advisory, issued at 27/1500 UTC, placed the weakening
system roughly 600 nm west of Cabo San Lucas. By later in the day it
had deteriorated into a large remnant LOW which drifted westward for
a few more days before losing its identity.
No damage or casualties have been attributed to Hurricane Ileana.
(Report written by Gary Padgett)
HURRICANE JOHN
(TC-11E)
28 August - 4 September
-------------------------------------------
Hurricane John became the first Eastern Pacific hurricane to make
landfall in Mexico since Hurricane Marty in September, 2003. A tropical
wave entered the Eastern North Pacific on 25 August and almost
immediately began to show signs of organization. However, the system
did not develop into a tropical depression until 1200 UTC on the 28th
when it was located about 200 nm south of Salina Cruz, Mexico. The
first advisory on Tropical Depression 11E was issued at 1500 UTC, and
at 2100 UTC Tropical Storm John was christened. John began moving on
a west-northwesterly track parallel to the coast of Mexico and steadily
intensified, becoming an 80-kt hurricane by 29/1800 UTC when located
about 165 nm south-southeast of Acapulco. John actually underwent an
episode of rapid intensification on the 29th with its MSW increasing
from 60 kts to 100 kts in twelve hours. By 1800 UTC on 30 August John
had become a Category 4 hurricane about 165 nm west of Acapulco with
winds estimated at 115 kts--the peak for the hurricane's history.
Hurricane John subsequently underwent an eyewall replacement cycle
which, in conjunction with land interaction as the storm moved very
near the coast, led to a gradual weakening of the cyclone. Although
the eye remained offshore, the storm's circulation affected portions
of Mexico with very heavy rains and strong winds. Significant storm
surge flooding was reported in Acapulco. As the hurricane rounded
Cabo Corrientes, its track bent slightly more toward the northwest,
drawing a bead on the Cabo San Lucas area. Fortunately, however, John
had weakened to a 90-kt Category 2 hurricane by 0000 UTC on 1 September.
After moving further away from the Mexican mainland, the winds increased
to 100 kts briefly at 01/1200 UTC, but soon began to drop again due to
another eyewall replacement cycle. John's track continued to bend ever
so slightly to the northwest, sparing the Cabo area. However, areas
further north on the eastern side of the Baja Peninsula were not so
lucky.
Hurricane John's eye made landfall near Cabo del Este around 0300
UTC on 2 September with the MSW estimated at 95 kts. The eye of John
passed very near La Paz around 02/0900 UTC with winds having weakened
to near 85 kts. The storm continued moving north-northwestward along
the eastern Baja coastline and eventually made a second landfall (after
crossing the Bahia La Paz) as a Category 1 hurricane. Once inland over
the Peninsula, John continued to slowly weaken and was downgraded to a
tropical storm at 02/2100 UTC. The center remained near the Gulf of
California and weakening proceeded rather slowly. John was finally
downgraded to a tropical depression at 0000 UTC on 4 September about
45 nm (80 km) northwest of Santa Rosalia, Mexico. Later that morning
TPC/NHC issued the final advisory on John. Most of the convection had
decoupled from the circulation and was moving towards the mainland and
a clear LLCC had not been discernible for 24 hours.
Hurricane John had adverse effects on widespread regions of Mexico.
Storm surge flooding and strong winds left damage in the Acapulco area,
and a significant portion of the western coast of mainland Mexico
experienced heavy rainfall, which led to flooding and landslides.
Many trees were downed in the La Paz area with 200 homes completely
destroyed. Thousands of poorly-constructed houses were destroyed in
the Baja California region. In Ciudad Juarez, across the border from
El Paso, Texas, rainfall from the storm's remnants led to flooding,
downed power lines, and was responsible for several traffic accidents.
Total damage in Mexico from the storm amounted to $60.8 million (USD)
with six fatalities attributed to Hurricane John.
Some of the above information was taken from the excellent online
Wikipedia report on Hurricane John, accessible at the following URL:
http://en.wikipedia.org/wiki/Hurricane_John_%282006%29
(Report written by Gary Padgett)
HURRICANE KRISTY
(TC-12E)
30 August - 8 September
-------------------------------------------
The final tropical cyclone of a very busy August began with an area
of disturbed weather associated with a tropical wave. The system was
upgraded to Tropical Depression 12E at 0300 UTC on 30 August while
centered about 475 nm south-southwest of Cabo San Lucas. TD-12E quickly
intensified and was upgraded to Tropical Storm Kristy six hours later.
The intensification trend continued as Kristy moved northwestward far
to the southwest of the Baja California Peninsula. The cyclone was
upgraded to hurricane status at 0900 UTC on the 31st based upon Dvorak
ratings ranging from T3.5 to T4.5, plus a couple of microwave passes
indicating a possible developing eyewall. Kristy remained a hurricane
for 24 hours, but never intensified above minimal hurricane strength of
65 kts. By the morning of 1 September cloud top temperatures near the
center were warming as the cyclone began losing its deep convection.
Concurrently, the cloud mass was becoming less organized, so Kristy was
downgraded to a tropical storm at 01/0900 UTC. Continued weakening was
forecast due to cooler SSTs and increased vertical shear from strong
Hurricane John located not too far to the east.
By 2 September steering currents had become weak and Kristy meandered
for the next couple of days, drifting to the south and southeast. The
cyclone had become situated under an outflow channel of Hurricane John
and the resultant east to east-southeasterly shear led to further
weakening. Kristy was downgraded to a tropical depression at 2100 UTC
on the 2nd about 550 nm west-southwest of Cabo San Lucas. Continued
weakening and dissipation in two days was forecast, but surprises always
happen with tropical cyclones. By the afternoon of the 3rd an area of
strong convection had developed with cloud top temperatures below -70 C,
so Kristy was re-upgraded to tropical storm intensity at 03/2100 UTC.
No further strengthening was anticipated, and the forecast called for
dissipation in three days. This new forecast seemed to be verifying
as Kristy was downgraded back to depression status twelve hours later.
However, never say never! As the 4th progressed Tropical Depression
Kristy began a slow but steady trek to the west as a subtropical ridge
to the north began to build. Early on the 5th a strong burst of
convection occurred near the center and persisted for several hours.
Dvorak T-numbers once more increased to tropical storm strength, so
the tenacious Kristy was upgraded to tropical storm status for the third
time, being centered about 740 nm west-southwest of Cabo San Lucas.
By afternoon the convective bursts had morphed into bands, giving the
appearance of an intensifying tropical cyclone. Based on satellite
intensity estimates, Kristy's intensity was bumped up to 40 kts at
05/2100 UTC. Further intensification up to 50 kts was forecast within
24 hours. However, the extent and depth of the convection soon began
to diminish and Kristy's MSW was lowered back to 35 kts at 06/0300 UTC.
With Kristy's history of intensity fluctuations, some further modest
strengthening was forecast, but this failed to materialize.
Entrainment of dry, stable air from the northwest led to a continued
decrease in deep convection, in spite of still-warm SSTs and light shear,
and Kristy was downgraded to a tropical depression for the final time
at 06/2100 UTC. The system continued to moved slightly south of west
for the next couple of days as it slowly spun down. Since the forecast
track kept Kristy over marginally warm SSTs with low shear, the 07/0300
UTC advisory called for Kristy to maintain itself as a 30-kt depression
for several more days. However, by 0300 UTC on the 8th Kristy had been
devoid of organized deep convection for more than 24 hours so TPC/NHC
issued the final advisory at that time, placing the center approximately
1300 nm west-southwest of Cabo San Lucas.
No deaths or damages have been attributed to Hurricane Kristy.
(Report written by Gary Padgett)
*************************************************************************
NORTHWEST PACIFIC (NWP) - North Pacific Ocean West of Longitude 180
Activity for August: 3 tropical depressions **
3 tropical storms
2 typhoons ++
2 super typhoons &&
** - two of these were classified as weak depressions by JMA only
++ - one of these formed in late July and continued into early August
&& - one of these was a visitor from the Central North Pacific and
continued into early September
NOTE!!! The Northwest Pacific basin will be covered in the third
installment of the August summary.
*************************************************************************
NORTH INDIAN OCEAN (NIO) - Bay of Bengal and Arabian Sea
Activity for August: 3 depressions
1 deep depression
NOTE!!! The North Indian Ocean basin will be covered in the third
installment of the August summary.
*************************************************************************
SOUTHWEST INDIAN OCEAN (SWI) - South Indian Ocean West of Longitude 90E
Activity for August: No tropical cyclones
*************************************************************************
NORTHWEST AUSTRALIA/SOUTHEAST INDIAN OCEAN (AUW) - From 90E to 135E
Activity for August: No tropical cyclones
*************************************************************************
NORTHEAST AUSTRALIA/CORAL SEA (AUE) - From 135E to 160E
Activity for August: No tropical cyclones
*************************************************************************
SOUTH PACIFIC (SPA) - South Pacific Ocean East of Longitude 160E
Activity for August: 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:
ftp://ftp.nhc.noaa.gov/pub/products/nhc/recon/
Information regarding how to interpret the coded reconnaissance
messages may be found at the following URL:
http://www.nhc.noaa.gov/reconlist.shtml
Links are also included to websites with further information about the
U. S. Air Force 53rd Weather Reconnaissance Squadron and the NOAA Air-
craft Operations Center.
(2) Archived Advisories
-----------------------
All the advisory products (public advisories, forecast/advisories,
strike probabilities, discussions, various graphics) issued by TPC/NHC
are archived on TPC's website. For the current year (using 2004 as an
example), the archived products can be found at:
http://www.nhc.noaa.gov/archive/2004/index.shtml
Links to tropical products archives for earlier years are available at
the following URL:
http://www.nhc.noaa.gov/pastall.shtml
JTWC warnings for past storms are archived on the NRL Monterry website:
http://www.nrlmry.navy.mil/tc_pages/tc_home.html
On the NRL site, the link to past years can be found in the upper left
corner of the screen.
I am not aware at the moment of any other TCWC which archives all
its tropical cyclone warning/advisory products for public access, but
if I learn of any, I will add them to this list.
(3) Satellite Imagery
---------------------
Satellite images of tropical cyclones in various sensor bands are
available on the NRL Monterrey and University of Wisconsin websites,
courtesy of Jeff Hawkins and Chris Velden and their associates. The
links are:
http://www.nrlmry.navy.mil/tc_pages/tc_home.html
http://cimss.ssec.wisc.edu/tropic/tropic.html
On the NRL site, the link to past years can be found in the upper left
corner of the screen. For the CIMSS site, a link to data archives is
located in the lower left portion of the screen.
Additional tropical satellite imagery, along with looping ability for
composite microwave imagery for the Western Hemisphere north of the
equator, can be found at:
(1) For the Eastern North Pacific:
http://www.ssd.noaa.gov/PS/TROP/trop-epac.html
(2) For the Atlantic, Gulf of Mexico and Caribbean Sea:
http://www.ssd.noaa.gov/PS/TROP/trop-atl.html
I'm sure there are other sites with available imagery available, and
as I learn of them, I will add the links to this list.
*************************************************************************
EXTRA FEATURE
In order to shorten the amount of typing in preparing the narrative
material, I have been in the habit of freely using abbreviations and
acronyms. I have tried to define most of these with the first usage
in a given summary, but I may have missed one now and then. Most of
these are probably understood by a majority of readers but perhaps a
few aren't clear to some. To remedy this I developed a Glossary of
Abbreviations and Acronyms which I first included in the August, 1998
summary. I don't normally include the Glossary in most months in
order to help keep them from being too long. If anyone would like to
receive a copy of the Glossary, please e-mail me and I'll be happy
to send them a copy.
*************************************************************************
AUTHOR'S NOTE: This summary should be considered a very preliminary
overview of the tropical cyclones that occur in each month. The cyclone
tracks (provided separately) will generally be based upon operational
warnings issued by the various tropical cyclone warning centers. The
information contained therein may differ somewhat from the tracking and
intensity information obtained from a "best-track" file which is based
on a detailed post-seasonal analysis of all available data. Information
on where to find official "best-track" files from the various warning
centers will be passed along from time to time.
The track files are not being sent via e-mail. They can be retrieved
from the archive sites listed below. (Note: I do have a limited e-mail
distribution list for the track files. If anyone wishes to receive
these via e-mail, please send me a message.)
Both the summaries and the track files are standard text files
created in DOS editor. Download to disk and use a viewer such as
Notepad or DOS editor to view the files.
The first summary in this series covered the month of October,
1997. Back issues can be obtained from the following websites
(courtesy of Michael Bath, Michael V. Padua, Michael Pitt, Chris
Landsea, and John Diebolt):
http://australiasevereweather.com/cyclones/
http://www.typhoon2000.ph <http://www.typhoon2000.ph/>
http://mpittweather.com <http://mpittweather.com/>
ftp://ftp.aoml.noaa.gov/hrd/pub/landsea/padgett/
http://www.tropicalcyclone2005.com/
Another website where much information about tropical cyclones may
be found is the website for the UK Meteorological Office. Their site
contains a lot of statistical information about tropical cyclones
globally on a monthly basis. The URL is:
http://www.metoffice.gov.uk/weather/tropicalcyclone
TROPICAL CYCLONE REPORTS AVAILABLE
JTWC now has available on its website the Annual Tropical Cyclone
Report (ATCR) for 2004 (2003-2004 season for the Southern Hemisphere).
ATCRs for earlier years are available also.
The URL is: http://199.10.200.33/jtwc.html
Also, TPC/NHC has available on its webpage nice "technicolor"
tracking charts for the 2005 Atlantic and Eastern North Pacific
tropical cyclones; also, storm reports for all the 2005 Atlantic
and Eastern North Pacific cyclones are now available, as well as
track charts and reports on storms from earlier years.
The URL is: http://www.nhc.noaa.gov <http://www.nhc.noaa.gov/>
A special thanks to Michael Bath of McLeans Ridges, New South Wales,
Australia, for assisting me with proofreading the summaries.
PREPARED BY
Gary Padgett
E-mail: garyp@alaweb.com
Phone: 334-222-5327
Kevin Boyle (Northwest Pacific)
E-mail: newchapelobservatory@btinternet.com
Simon Clarke (Northeast Australia/Coral Sea, South Pacific)
E-mail: scla4255@bigpond.net.au
*************************************************************************
*************************************************************************
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