[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 040002
TWDAT

TROPICAL WEATHER DISCUSSION...CORRECTION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT WED SEP 03 2008

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF
SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE
EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE
IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND
RADAR.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2315 UTC.

...SPECIAL FEATURES...

TROPICAL DEPRESSION GUSTAV IS NEARLY STATIONARY OVER SW ARKANSAS
WITH HEAVY RAIN CONTINUING OVER MISSOURI AND THE LOWER
MISSISSIPPI VALLEY. AT 03/2100Z...ITS CENTER WAS LOCATED NEAR
33.8N 94.2W OR ABOUT 20 NM N-NW OF TEXARKANA ARKANSAS AND ABOUT
70 NM SOUTHWEST OF HOT SPRINGS ARKANSAS. A GRADUAL TURN TOWARD
THE NORTHEAST AND AN INCREASE IN FORWARD SPEED IS EXPECTED
TONIGHT AND THURSDAY AS GUSTAV INTERACTS WITH A FRONTAL BOUNDARY
AND BECOMES EXTRATROPICAL. MAXIMUM SUSTAINED WINDS ARE 22 KT
WITH HIGHER GUSTS. THE MINIMUM CENTRAL PRESSURE IS 998 MB.
SATELLITE IMAGERY AND DOPPLER RADAR CONTINUE TO SHOW THE BROAD
CIRCULATION OF GUSTAV WITH NARROW OUTER RAINBANDS OF SCATTERED
SHOWERS OVER THE N/CENTRAL GULF OF MEXICO AND FLORIDA
PANHANDLE.

TROPICAL STORM HANNA IS CENTERED NEAR 22.6N 71.8W OR ABOUT 175
NM EAST-SOUTHEAST OF SAN SALVADOR IN THE BAHAMAS AND ABOUT 340
NM EAST-SOUTHWEST OF NASSAU AT 04/0000 UTC MOVING N AT 12 KT. A
TURN TO THE NORTHWEST WITH AN INCREASE IN FORWARD SPEED IS
EXPECTED OVER THE NEXT 24 HOURS. ESTIMATED MINIMUM CENTRAL
PRESSURE IS 989 MB. MAXIMUM SUSTAINED WIND SPEED IS 55 KT WITH
GUSTS TO 65 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO
HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. UPPER LEVEL
RIDGING IN THE NRN SEMICIRCLE IS GENERATING SCATTERED MODERATE
TO STRONG CONVECTION ACROSS THE W ATLC FROM 23N-26N BETWEEN
67W-73W. SOUTHERLY MID-UPPER LEVEL FLOW ACROSS THE CENTRAL
CARIBBEAN IS PROVIDING ABUNDANT TROPICAL MOISTURE FOR SCATTERED
MODERATE/ISOLATED STRONG CONVECTION ACROSS THE ERN CARIBBEAN...
HISPANIOLA...PUERTO RICO AND THE VIRGIN ISLANDS FROM 14N-21N
BETWEEN 64W-74W. HANNA IS EXPECTED TO PRODUCE RAINFALL TOTALS OF
4 TO 8 INCHES...WITH MAXIMUM ISOLATED AMOUNTS OF 12 INCHES...
OVER THE SERN BAHAMAS...THE TURKS AND CAICOS ISLANDS...AND ERN
CUBA. ISOLATED AMOUNTS OF 15 INCHES ARE POSSIBLE IN PUERTO RICO.
RAINFALL TOTALS OF 6 TO 10 INCHES...WITH ISOLATED MAXIMUM
AMOUNTS OF UP TO 15 INCHES...ARE POSSIBLE OVER HISPANIOLA...
WHERE THESE RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS AND
MUD SLIDES. ON THE FORECAST TRACK...THE CENTER OF HANNA SHOULD
BE MOVING JUST EAST OF THE CENTRAL AND NORTHWESTERN BAHAMAS OVER
THE NEXT COUPLE OF DAYS WITH MODERATE TO LOCALLY HEAVY RAINFALL
POSSIBLE ACROSS THE BAHAMAS THURSDAY AND THE NORTH AND CENTRAL
EAST COAST OF FLORIDA BY FRIDAY MORNING.

HURRICANE IKE IS CENTERED NEAR 21.7N 53.2W OR ABOUT 560 NM
EAST-NORTHEAST OF THE LEEWARD ISLANDS AT 04/0000 UTC MOVING W-NW
AT 16 KT. THIS GENERAL MOTION IS EXPECTED TO CONTINUE THROUGH
THURSDAY...FOLLOWED BY A TURN TO THE WEST ON FRIDAY...TAKING IKE
OVER THE OPEN WATERS OF THE W/CENTRAL ATLC DURING THE NEXT
COUPLE OF DAYS. ESTIMATED MINIMUM CENTRAL PRESSURE IS 960 MB.
MAXIMUM SUSTAINED WIND SPEED IS 100 KT WITH HIGHER GUSTS. IKE IS
A DANGEROUS CATEGORY THREE HURRICANE ON THE SAFFIR-SIMPSON
HURRICANE SCALE. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/
WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. SATELLITE
IMAGERY OVER THE LAST FEW HOURS INDICATES THAT IKE HAS
INTENSIFIED...DEVELOPING AN EYE IN THE PROCESS. THE FORECAST
TRACKS IKE ALONG THE SOUTHERN PERIPHERY OF A BROAD UPPER LEVEL
HIGH ENCOMPASSING MUCH OF THE CENTRAL ATLC. NUMEROUS STRONG
CONVECTION IS WITHIN 100 NM OF THE CENTER IN ALL QUADRANTS.

TROPICAL STORM JOSEPHINE IS CENTERED NEAR 13.8N 29.9W OR ABOUT
225 NM WEST OF THE SOUTHERNMOST CAPE VERDE ISLANDS AT 03/2100
UTC MOVING W AT 11 KT. A WEST-NORTHWEST TRACK IS EXPECTED DURING
THE NEXT COUPLE OF DAYS. ESTIMATED MINIMUM CENTRAL PRESSURE IS
997 MB. MAXIMUM SUSTAINED WIND SPEED IS 50 KT WITH GUSTS TO 60
KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS
MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. LITTLE CHANGE IN
STRENGTH IS FORECAST THROUGH THURSDAY...BUT A WEAKENING TREND IS
FORECAST TO BEGIN ON FRIDAY. WATER VAPOR IMAGERY SHOWS UPPER
LEVEL WESTERLY FLOW ASSOCIATED WITH A TROUGH TO THE WEST THAT
WILL PROVIDE INCREASED UPPER LEVEL SHEAR. CONVECTION THIS
EVENING CONTINUES TO STRUGGLE SHOWING LITTLE ORGANIZATION WITH
SCATTERED MODERATE CONVECTION FROM 13N-17N BETWEEN 26W-30W
LOCATED PRIMARILY IN THE NE QUADRANT.

...TROPICAL WAVES...

A TROPICAL WAVE IS NEARLY READY TO EMERGE OFF THE W AFRICAN
COAST. THE VERTICAL SOUNDING FROM DAKAR THIS MORNING SHOWS NE
WINDS AT LOW LEVELS. SCATTERED SHOWERS/ISOLATED TSTMS ARE ACROSS
INTERIOR SENEGAL...GAMBIA...AND GUINEA BISSAU THIS EVENING.

...THE ITCZ...

THE ITCZ AXIS IS ANALYZED ALONG 10N13W 8N17W 10N24W 9N32W 7N45W
11N59W. NO ORGANIZED CONVECTIVE CLUSTERS ARE OBSERVED.

...DISCUSSION...

GULF OF MEXICO...
A WEAK SURFACE RIDGE IS POSITIONED ACROSS THE GULF OF MEXICO IN
THE WAKE OF T.D. GUSTAV THAT IS INLAND OVER SWRN ARKANSAS.
ISOLATED SHOWERS REMAIN IN PREDOMINATELY SOUTHERLY SURFACE FLOW
N OF 26N AND CONTINUE TO STREAM INTO THE INLAND CIRCULATION OF
GUSTAV. AN UPPER LEVEL RIDGE CENTERED OVER SRN BAJA CALIFORNIA
EXTENDS ACROSS NE MEXICO TO NEAR SE LOUISIANA AND COVERS THE
GULF W OF 80W...INCLUDING THE FLORIDA PENINSULA. UPPER LEVEL
DIFFLUENCE AND A WEAK 1008 MB SURFACE LOW CENTERED NEAR 19N94W
ARE GENERATING AN AREA OF SCATTERED SHOWERS AND TSTMS ACROSS THE
WRN YUCATAN PENINSULA...SRN MEXICO AND ADJACENT COASTAL WATERS
IN THE BAY OF CAMPECHE. MODERATE TO STRONG SUBSIDENCE/DRY AIR IS
NOTED OVER THE WESTERN GULF N OF 22N AND W OF 91W.

CARIBBEAN SEA...
THE MAIN WEATHER PRODUCER ACROSS THE CARIBBEAN IS T.S. HANNA AND
THE CONVECTIVE BANDS OF PRECIPITATION ACROSS THE ERN PORTION OF
THE BASIN...SEE SPECIAL FEATURES ABOVE FOR DETAILS. AREAS OF
HEAVY RAINFALL...GUSTY WINDS AND LOCALIZED FLOODING ARE ALSO
AFFECTING LARGE SECTIONS OF PUERTO RICO...THE VIRGIN ISLANDS...
AND THE DOMINICAN REPUBLIC...INCLUDING THE MONA AND ANEGADA
PASSAGES. RAINBANDS OF SCATTERED SHOWERS/ISOLATED TSTMS
ASSOCIATED WITH THE OVERALL CIRCULATION OF HANNA COVER THE AREA
FROM 14N-20N BETWEEN 64W-73W. A LINE OF SCATTERED SHOWERS/TSTMS
ALSO EXTENDS WITHIN 50 NM OF A LINE FROM 16N74W SW TO 13N78W.
THE AFOREMENTIONED UPPER RIDGE ACROSS MEXICO EXTENDS OVER THE NW
CARIBBEAN PROVIDING UPPER DIFFLUENCE TO GENERATE SCATTERED
SHOWERS/TSTMS ACROSS SRN HONDURAS AND NRN NICARAGUA. AN UPPER
LEVEL RIDGE FROM THE SW ATLC EXTENDS ACROSS THE ERN CARIBBEAN
PROVIDING SUBSIDENCE/DRY AIR E OF 63W.

ATLANTIC OCEAN...
THREE TROPICAL CYCLONES ARE LOCATED IN THE DISCUSSION AREA...SEE
SPECIAL FEATURES ABOVE FOR DETAILS. AN UPPER LOW IS CENTERED SW
OF THE BAHAMAS NEAR 23N77W. THIS LOW IS BRINGING MODERATE TO
STRONG SUBSIDENCE/DRY AIR SOUTH OVER THE EAST COAST OF FLORIDA
AND THE NW BAHAMAS. AN LARGE EXPANSIVE UPPER LEVEL HIGH IS IN
THE CENTRAL ATLC CENTERED NEAR 28N52W AND COVERS THE ATLC N OF
12N BETWEEN 42W-73W. AN UPPER LEVEL TROUGH EXTENDS SW ACROSS THE
ERN ATLC TO AN NEAR CUT-OFF UPPER LEVEL LOW LOCATED NEAR 20N36W.
UPPER-LEVEL ELY WINDS DOMINATE MOST OF THE DEEP TROPICS W OF
38W. AT THE SURFACE...A 1026 MB HIGH LOCATED NEAR 35N42W EXTENDS
A RIDGE OVER PARTS OF THE CENTRAL AND ERN ATLC E OF 50W. THE SRN
EXTENT OF A DISSIPATING STATIONARY FRONT ENTERS THE AREA NEAR
32N60W WITH SCATTERED SHOWERS/TSTMS E OF THE FRONT FROM 30N-32N
BETWEEN 57W-60W.

$$
HUFFMAN

This weather bulletin was brought to you by:
www.nashvilleweather.net