EPAC: MONTHLY TROPICAL WEATHER SUMMARY

[HURAKAN]

742
ABPZ30 KNHC 011258
TWSEP
MONTHLY TROPICAL WEATHER SUMMARY
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM PDT SAT SEP 1 2007

FOR THE EASTERN NORTH PACIFIC...EAST OF 140 DEGREES WEST LONGITUDE..

TROPICAL CYCLONE ACTIVITY IN THE EASTERN PACIFIC OCEAN WAS BELOW
AVERAGE FOR AUGUST. HURRICANE FLOSSIE AND TROPICAL STORMS GIL AND
HENRIETTE FORMED DURING THE MONTH. TROPICAL STORM ERICK ALSO
DISSIPATED EARLY IN THE MONTH AFTER THE SYSTEM GENERATED IN JULY.
IN COMPARISON...THE AVERAGE AUGUST HAS ABOUT 4 TROPICAL STORMS...2
OF WHICH BECOME HURRICANES. ALTHOUGH THE NUMBER OF TROPICAL STORMS
AND HURRICANES IS ONLY SLIGHTLY BELOW AVERAGE...IN TERMS OF THE
ACCUMULATED CYCLONE ENERGY (ACE) INDEX...WHICH MEASURES THE
COMBINED STRENGTH AND DURATION OF NAMED STORMS AND HURRICANES...
THIS WAS THE THIRD QUIETEST AUGUST (BEHIND 1977 AND 1973) SINCE
RELIABLE RECORDS BEGAN IN THE EASTERN PACIFIC BASIN IN 1971.

ERICK FORMED FROM A TROPICAL WAVE THAT ENTERED THE EASTERN PACIFIC
ON 24 JULY. THE WAVE GRADUALLY BECAME BETTER ORGANIZED...FORMING A
BROAD SURFACE LOW ALONG THE WAVE ON 28 JULY. THUNDERSTORM ACTIVITY
CONSOLIDATED NEAR THE LOW ON 31 JULY AND ORGANIZED INTO A TROPICAL
DEPRESSION LATE IN THE DAY...LOCATED ABOUT 925 NM SOUTHWEST OF THE
SOUTHERN TIP OF BAJA CALIFORNIA. THE DEPRESSION BECAME A TROPICAL
STORM EARLY ON 1 AUGUST...REACHING A PEAK INTENSITY OF 35 KT. ERICK
WEAKENED INTO A TROPICAL DEPRESSION AT 0000 UTC 2 AUGUST AND
DEGENERATED INTO A TROPICAL WAVE SIX HOURS LATER ABOUT 1200 N MI
WEST-SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA.

FLOSSIE DEVELOPED FROM AN AREA OF DISTURBED WEATHER THAT HAD BEEN
TRACKED WESTWARD ACROSS THE EASTERN NORTH PACIFIC FOR SEVERAL DAYS.
THE SYSTEM ORGANIZED INTO A TROPICAL DEPRESSION ON 8 AUGUST
CENTERED ABOUT 1100 N MI WEST-SOUTHWEST OF THE SOUTHERN TIP OF BAJA
CALIFORNIA. IT BECAME A TROPICAL STORM BY EARLY ON 9 AUGUST.
MOVING GENERALLY WESTWARD...FLOSSIE CONTINUED TO STRENGTHEN AND ON
10 AUGUST AN EYE BECAME EVIDENT...SIGNIFYING THAT THE SYSTEM HAD
INTENSIFIED INTO A HURRICANE WHILE CENTERED ABOUT 1200 N MI EAST-
SOUTHEAST OF THE HAWAIIAN ISLANDS. FLOSSIE STRENGTHENED FURTHER
AND IT BECAME A MAJOR HURRICANE EARLY ON 11 AUGUST...AND A CATEGORY
4 HURRICANE A LITTLE LATER THAT DAY JUST BEFORE CROSSING INTO THE
CENTRAL PACIFIC HURRICANE BASIN. FOR FURTHER INFORMATION ON
FLOSSIE...SEE THE AUGUST TROPICAL WEATHER SUMMARY BY THE CENTRAL
PACIFIC HURRICANE CENTER UNDER WMO HEADER ACPN60 PHFO AND UNDER
AWIPS HEADER HFOTWSCP.

GIL ORIGINATED FROM A TROPICAL WAVE THAT ENTERED THE EASTERN PACIFIC
ON 23 AUGUST. AN AREA OF LOW PRESSURE DEVELOPED ALONG THE WAVE AXIS
SOUTH OF THE GULF OF TEHUANTEPEC ON 25 AUGUST. THE LOW MOVED
SLOWLY WEST-NORTHWESTWARD OVER THE NEXT SEVERAL DAYS WITH SHOWER
AND THUNDERSTORM ACTIVITY GRADUALLY INCREASING. BY THE MORNING OF
29 AUGUST THE SYSTEM GAINED ENOUGH ORGANIZATION TO BE DESIGNATED AS
A TROPICAL DEPRESSION...LOCATED ABOUT 220 N MI SOUTH OF THE
SOUTHERN TIP OF BAJA CALIFORNIA. DESPITE MODERATE EASTERLY
SHEAR...THE DEPRESSION BECAME A TROPICAL STORM JUST SIX HOURS LATER
AS CONVECTION INCREASED AND DEEPENED. STRONG HIGH PRESSURE
ANCHORED OVER THE SOUTHWESTERN UNITED STATES STEERED GIL ON A
GENERAL WESTWARD TRACK FOR THE NEXT SEVERAL DAYS. A STABLE
ENVIRONMENT AND EASTERLY SHEAR HAMPERED MUCH STRENGTHENING...AND
GIL REACHED A PEAK INTENSITY OF 40 KT AT 1800 UTC 30 AUGUST...ABOUT
330 MILES SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA. BY THE
END OF THE MONTH GIL WEAKENED TO A TROPICAL DEPRESSION WITH 30 KT
WINDS...ABOUT 575 N MI WEST-SOUTHWEST OF THE SOUTHERN TIP OF BAJA
CALIFORNIA.

HENRIETTE ORIGINATED FROM A TROPICAL WAVE THAT MOVED OFF THE COAST
OF CENTRAL AMERICA ON 28 AUGUST...AND PRODUCED DISORGANIZED
SHOWERS AND THUNDERSTORMS FOR THE NEXT DAY OR SO. BY LATE IN THE
DAY ON 29 AUGUST A SMALL AREA OF LOW PRESSURE DEVELOPED...ABOUT 305
N MI SOUTH-SOUTHEAST OF ACAPULCO MEXICO. SHOWER AND THUNDERSTORM
ACTIVITY SURROUNDING THE LOW IMPROVED IN ORGANIZATION...AND AT 1800
UTC ON 30 AUGUST THE SYSTEM WAS DESIGNATED AS A TROPICAL
DEPRESSION...ABOUT 220 N MI SOUTHEAST OF ACAPULCO MEXICO. THE
CYCLONE TRACKED TOWARD THE WEST-NORTHWEST IN RESPONSE TO A WEAKNESS
IN THE SUBTROPICAL RIDGE OVER THE WESTERN GULF OF MEXICO. THE
DEPRESSION GAINED ORGANIZATION AS IT MOVED PARALLEL TO THE SOUTH
COAST OF MEXICO AND BECAME TROPICAL STORM HENRIETTE AT 1200 UTC 31
AUGUST...LOCATED ABOUT 75 N MI SOUTH OF ACAPULCO MEXICO. AT
MONTH'S END...HENRIETTE WAS ON A STRENGTHENING TREND AND BRINGING
RAINFALL AND TROPICAL STORM FORCE WINDS ALONG PORTIONS OF THE
PACIFIC COAST OF MEXICO.

SUMMARY TABLE

NAME DATES MAX WIND (KT) DEATHS
-------------------------------------------------------
TS ERICK 31 JUL- 2 AUG 35 0
H FLOSSIE 8 AUG-16 AUG 120 0
TS GIL 29 AUG- 40 0
TS HENRIETTE 30 AUG- 45 *
-------------------------------------------------------

NOTE...DATES BASED ON COORDINATED UNIVERSAL TIME (UTC)
* UNKNOWN AT THIS TIME

$$

FORECASTER BLAKE/MAINELLI

[Chacor]

ACPN60 PHFO 011515
TWSCP

TROPICAL WEATHER SUMMARY FOR THE CENTRAL NORTH PACIFIC
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI
530 AM HST SAT SEP 1 2007

FOR THE CENTRAL NORTH PACIFIC...BETWEEN 140W AND 180

THERE WAS ONE TROPICAL CYCLONE IN THE CENTRAL PACIFIC HURRICANE
CENTER /CPHC/ AREA OF RESPONSIBILITY DURING THE MONTH OF AUGUST 2007.

HURRICANE FLOSSIE CROSSED LONGITUDE 140W INTO THE CENTRAL NORTH
PACIFIC DURING THE MORNING OF 11 AUGUST. THE NATIONAL HURRICANE
CENTER HAD BEEN ISSUING ADVISORIES ON THIS TROPICAL CYCLONE SINCE 8
AUGUST. FLOSSIE WAS A VERY IMPRESSIVE HURRICANE WITH A DISTINCT EYE
EMBEDDED WITHIN A SOLID EYEWALL AND A VERY IMPRESSIVE UPPER LEVEL
OUTFLOW PATTERN AS IT ENTERED THE CPHC AREA OF RESPONSIBILITY. THE
HURRICANE MAINTAINED MAXIMUM SUSTAINED WIND SPEEDS OF 130 TO 140 MPH
FOR THE NEXT TWO DAYS. FLOSSIE WAS A RELATIVELY SMALL TROPICAL
CYCLONE WITH SUSTAINED WINDS OF 39 MPH OR GREATER EXTENDING OUT
ABOUT 100 MILES FROM THE CENTER IN THE NORTHERN SEMICIRCLE DURING
THIS SAME TIME PERIOD. FLOSSIE MOVED TOWARD THE WEST NORTHWEST AT
ABOUT 13 MPH SOUTH OF A STRONG SUBTROPICAL RIDGE AS IT APPROACHED
THE HAWAIIAN ISLANDS. VERTICAL WIND SHEAR WAS MINIMAL IN THE
VICINITY OF THIS HURRICANE DURING THE FIRST FEW DAYS IT WAS OVER THE
CENTRAL NORTH PACIFIC OCEAN. ALSO...THE SYSTEM WAS ABLE TO DERIVE
SUFFICIENT HEAT ENERGY FROM THE OCEAN TO MAINTAIN ITS INTENSITY.

A HURRICANE WATCH WAS ISSUED FOR THE BIG ISLAND EARLY ON THE MORNING
OF 13 AUGUST DUE TO THE CLOSE PROXIMITY OF THE PROJECTED TRACK...AS
WELL AS THE INTENSITY FORECAST MAINTAINING FLOSSIE AS A HURRICANE
WHEN IT ARRIVED IN THE VICINITY OF THE SOUTHERN END OF THAT ISLAND.
A TROPICAL STORM WARNING WAS HOISTED FOR THE BIG ISLAND LATER THAT
SAME MORNING. FORTUNATELY...THE LONG ANTICIPATED INCREASE IN
VERTICAL WIND SHEAR TOOK ITS TOLL ON FLOSSIE DURING 14 AUGUST. AS A
RESULT...FLOSSIE WEAKENED TO A TROPICAL STORM THAT EVENING. AS IT
WAS PASSING FAR SOUTH OF THE ISLANDS OF OAHU AND KAUAI...FLOSSIE
WEAKENED TO A TROPICAL DEPRESSION LATE ON 15 AUGUST DUE TO VERY
STRONG VERTICAL WIND SHEAR. CPHC ISSUED THE FINAL ADVISORY ON
DISSIPATING TROPICAL DEPRESSION FLOSSIE DURING THE EARLY MORNING
HOURS OF 16 AUGUST.

EVEN THOUGH THE CENTER OF FLOSSIE PASSED ABOUT 100 MILES DUE SOUTH
OF SOUTH POINT ON THE BIG ISLAND OF HAWAII...IT GENERATED VERY LARGE
WAVES ALONG THE SOUTHEAST FACING SHORELINE OF THAT ISLAND. SURF
HEIGHTS WERE ESTIMATED TO BE NEAR 20 FEET. IN FACT... COINCIDENT
WITH THE PASSAGE OF FLOSSIE...A 44 ACRE LAVA BENCH SLIPPED INTO THE
OCEAN DURING THE NIGHT ON 13 AUGUST. IT IS POSSIBLE THIS LOSS OF
SHORELINE WAS DUE TO THE LARGE SURF FROM THE HURRICANE OR A 5.4
MAGNITUDE EARTHQUAKE THAT OCCURRED AROUND THE SAME TIME. FLOSSIE
WEAKENED AND REMAINED FAR ENOUGH SOUTH OF THE BIG ISLAND DURING ITS
CLOSEST POINT OF APPROACH ON 14 AUGUST TO PREVENT ANY EXCESSIVE
RAINFALL AMOUNTS. HOWEVER...SUSTAINED WIND SPEEDS OF AT LEAST 39 MPH
WERE REPORTED AT SOUTH POINT AS FLOSSIE PASSED BY. NO SIGNIFICANT
DAMAGE OR INJURIES WERE REPORTED ON THE BIG ISLAND.

SUMMARY TABLE

NAME DATES MAX. WIND EST. MINIMUM PRESSURE
--------------------------------------------------------------
HURR FLOSSIE 11-16 AUG 120 KT/140 MPH 946 MB/27.94 IN

FOR ADDITIONAL INFORMATION...VISIT THE CENTRAL PACIFIC HURRICANE
CENTER WEB SITE AT.../IN LOWERCASE/...WWW.WEATHER.GOV/CPHC

THE NEXT TROPICAL WEATHER SUMMARY WILL BE ISSUED ON OCTOBER 1...
2007.

$$
HOUSTON/BIRCHARD/KODAMA/TANABE/RBALLARD

[Chacor]

Amazing how Flossie can fill out three paragraphs in the CPac TWS (almost a TCR on Flossie, just without BT!) when EPac TWS has four paragraphs.