Atlantic Hurricane Outlook & Discussion

	Expires:No;;820854
ABNT20 KNHC 272348
TWOAT 
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT WED AUG 27 2008
FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...
THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
STORM GUSTAV...LOCATED ABOUT 65 MILES SOUTH OF GUANTANAMO CUBA. 
THUNDERSTORM ACTIVITY HAS BECOME MORE CONCENTRATED THIS EVENING WITH
THE LOW PRESSURE SYSTEM CENTERED ABOUT 375 MILES EAST-NORTHEAST OF
THE NORTHERN LEEWARD ISLANDS. ENVIRONMENTAL CONDITIONS ARE EXPECTED
TO BECOME MORE CONDUCIVE FOR A TROPICAL DEPRESSION TO FORM TONIGHT
OR TOMORROW AS IT DRIFTS NORTHWESTWARD.
A LARGE TROPICAL WAVE LOCATED OVER THE FAR EASTERN ATLANTIC ABOUT
650 MILES WEST OF THE CAPE VERDE ISLANDS CONTINUES TO PRODUCE
DISORGANIZED SHOWER AND THUNDERSTORM ACTIVITY. SOME SLOW DEVELOPMENT
OF THIS SYSTEM IS POSSIBLE OVER THE NEXT COUPLE OF DAYS AT IT MOVES
WESTWARD AT 10 TO 15 MILES PER HOUR.
ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.
$$ 
FORECASTER STEWART/FRANKLIN


Expires:No;;820934
AXNT20 KNHC 272358
TWDAT 
TROPICAL WEATHER DISCUSSION...
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT WED AUG 27 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 STORM GUSTAV IS CENTERED NEAR 19.0N 75.0W AT 28/0000 
UTC OR ABOUT 56 NM SOUTH OF GUANTANAMO CUBA MOVING WEST AT 6 KT. 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 999 MB. MAXIMUM SUSTAINED 
WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. PLEASE SEE THE LATEST 
NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 
KNHC AND/OR THE PUBLIC ADVISORY MIATCPAT2/WTNT32 KNHC FOR MORE 
DETAILS. A WNW TO W TRACK IS FORECAST DURING THE NEXT DAY OR TWO 
WITH A GRADUAL INCREASE IN FORWARD SPEED. ON THE FORECAST TRACK 
GUSTAV SHOULD PASS BETWEEN JAMAICA AND THE SE COAST OF CUBA ON 
THU. GRADUAL STRENGTHENING IS FORECAST AND GUSTAV COULD REGAIN 
HURRICANE STRENGTH ON THU AS IT MOVES FARTHER OUT OVER THE 
WARMER NRN CARIBBEAN SEA WATERS. SCATTERED MODERATE/STRONG 
CONVECTION IS WITHIN 90 NM OF THE CENTER IN THE SOUTHERN 
SEMICIRCLE. SIMILAR CONVECTION IS ASSOCIATED WITH AN OUTER BAND 
SOUTH OF JAMAICA FROM 15N-18N BETWEEN 75W-79W. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS FROM 15N-20N BETWEEN 
71W-75W. GUSTAV IS EXPECTED TO PRODUCE TOTAL RAINFALL 
ACCUMULATIONS OF 6 TO 12 INCHES OVER HAITI... EASTERN CUBA... 
JAMAICA...AND THE CAYMAN ISLANDS...WITH ISOLATED MAXIMUM AMOUNTS 
OF UP TO 25 INCHES POSSIBLE. THESE RAINS WILL LIKELY PRODUCE 
LIFE-THREATENING FLASH FLOODS AND MUD SLIDES.
A 1009 MB SURFACE LOW NEAR 19N57W IS SLOWLY DRIFTING WNW AND 
REMAINS FAVORABLE FOR DEVELOPMENT OVER THE NEXT DAY OR TWO. AN 
UPPER LEVEL RIDGE EXTENDS FROM THE ERN CARIBBEAN OUT INTO THE 
CENTRAL ATLC AND IS PROVIDING DIFFLUENCE ALOFT TO GENERATE 
SCATTERED MODERATE TO STRONG CONVECTION FROM 18N-21N BETWEEN 
53W-59W.
...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 34W S OF 21N MOVING W 15-20 KT. A 1009 MB 
LOW IS ANALYZED ALONG THE WAVE AXIS NEAR 16N WITH A BROAD AREA 
OF DEEP LAYERED MOISTURE EVIDENT ON SATELLITE IMAGERY. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS FROM 17N-19N BETWEEN 
31W-33W WITH SCATTERED SHOWERS FROM 16N-21N BETWEEN 31W-39W.
TROPICAL WAVE IS ALONG 48W S OF 17N MOVING W NEAR 20 KT. THIS 
WAVE EXHIBITS A LOW AMPLITUDE AND IS EMBEDDED WITHIN SOME RATHER 
DRY AIR. NO ASSOCIATED SHOWERS/DEEP CONVECTION. 
TROPICAL WAVE IN THE SW CARIBBEAN IS ALONG 81W S OF 13N MOVING W 
NEAR 20 KT. ALTHOUGH THIS WAVE REMAINS EMBEDDED WITHIN DEEP 
LAYERED MOISTURE AND THE ITCZ...SCATTERED MODERATE TO STRONG 
CONVECTION IS ACROSS INLAND WRN PANAMA AND COSTA RICA.
TROPICAL WAVE IN THE GULF OF MEXICO IS ALONG 97W S OF 20N  
MOVING W 15-20 KT. WAVE IS MOSTLY OVER S MEXICO AND THE E 
PACIFIC REGION PRODUCING SCATTERED MODERATE TO STRONG CONVECTION 
FROM 14N-18N BETWEEN 94W-97W.
...THE ITCZ...
THE ITCZ AXIS IS ANALYZED ALONG 17N16W 16N25W 12N32W 10N36W 
8N46W 7N50W 7N59W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE 
FROM 8N-14N BETWEEN 16W-21W. SCATTERED MODERATE CONVECTION IS 
WITHIN 90 NM OF THE AXIS BETWEEN 26W-33W. 
...DISCUSSION...
GULF OF MEXICO...
A MIDDLE TO UPPER TROUGH IS ACROSS THE CENTRAL AND WRN GULF OF 
MEXICO WITH AN UPPER HIGH REMAINING ANCHORED IN THE FLORIDA 
STRAITS NEAR 23N81W COVERING THE ERN GULF AND THE FLORIDA 
PENINSULA INTO THE W ATLC. UPPER DIFFLUENCE EAST OF THIS TROUGH 
IS GENERATING MULTILAYERED CLOUDINESS AND A FEW ISOLATED SHOWERS 
WITHIN 90 NM OF A LINE FROM APALACHICOLA BAY FLORIDA TO NEAR 
25N92W. A CLUSTER OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS 
ARE ALSO NOTED ACROSS SERN LOUISIANA DUE TO THE UPPER TROUGH. 
SCATTERED SHOWERS/THUNDERSTORMS ARE ACROSS THE SRN FLORIDA 
PENINSULA IN ASSOCIATION WITH THE UPPER DIFFLUENT PATTERN IN 
PLACE OVER THE REGION. WITH THE TROPICAL WAVE AND AN UPPER RIDGE 
ACROSS SRN MEXICO...SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE 
ACROSS THE YUCATAN PENINSULA AND SRN MEXICO. AT THE SURFACE...A 
WEAK 1015 MB HIGH PRESSURE IS CENTERED NEAR 27N86W AND IS 
KEEPING THE REMAINDER OF THE SE GULF WITH TRANQUIL WEATHER.
CARIBBEAN SEA...
THE MAIN CONCERN FOR THE CARIBBEAN IS T.S. GUSTAV BETWEEN HAITI 
AND CUBA...SEE SPECIAL FEATURES ABOVE. AN UPPER HIGH CENTERED 
OVER THE FLORIDA STRAITS COVERS THE NW CARIBBEAN AND IS 
PROVIDING UPPER LEVEL DIFFLUENCE TO PRODUCE CLUSTERS OF 
SCATTERED SHOWERS/THUNDERSTORMS ALONG THE SRN CUBA COASTLINE 
WITHIN 90 NM. THIS UPPER RIDGE IS KEEPING THE REMAINDER OF THE 
NW CARIBBEAN RELATIVELY CLEAR THIS EVENING. CLUSTERS OF 
SCATTERED SHOWERS AND THUNDERSTORMS ASSOCIATED WITH T.S. GUSTAV
ARE ACROSS THE CENTRAL CARIBBEAN SEA FROM 14N-20N BETWEEN 
70W-79W. AN UPPER LEVEL RIDGE IS ACROSS THE ERN CARIBBEAN NEAR 
16N67W AND IS PROVIDING UPPER DIFFLUENCE TO GENERATE SCATTERED 
SHOWERS/ISOLATED THUNDERSTORMS ACROSS THE MONA PASSAGE AND 
PUERTO RICO EXTENDING SOUTHEASTWARD TO ACROSS THE LESSER 
ANTILLES N OF SAINT LUCIA AND EAST OF 64W.
ATLANTIC OCEAN...
AN UPPER RIDGE ANCHORED IN THE FLORIDA STRAITS NEAR 23N81W 
COVERS THE W ATLC W OF 69W. A BROAD UPPER TROUGH ENCOMPASSES THE 
REMAINDER OF THE W ATLC FROM 58W-69W WITH AN EMBEDDED UPPER LOW 
N OF PUERTO RICO NEAR 22N65W GENERATING SCATTERED SHOWERS/ 
ISOLATED THUNDERSTORMS FROM 21N TO OVER THE ERN GREATER ANTILLES 
BETWEEN 64W-70W INCLUDING PUERTO RICO AND THE VIRGIN ISLANDS. A
SURFACE TROUGH IS ANALYZED ALONG 27N63W TO 21N66W GENERATING 
ISOLATED SHOWERS FROM 21N-25N BETWEEN 63W-68W. AN UPPER RIDGE 
EXTENDS FROM THE ERN CARIBBEAN TO NEAR 19N50W WITH A 1009 MB 
SURFACE LOW NEAR 19N57W AND COUPLED WITH THE UPPER LEVEL 
DIFFLUENCE IS GENERATING SCATTERED MODERATE TO STRONG CONVECTION 
FROM 18N-21N BETWEEN 53W-59W. SCATTERED MODERATE/ISOLATED STRONG 
CONVECTION ALSO EXTENDS S-SE FROM THE LOW FROM 14N-20N BETWEEN 
53W-56W. A SECOND BUT BENIGN UPPER LOW COVERS THE E/CENTRAL ATLC 
CENTERED NEAR 31N43W EXTENDING S TO 22N. AN UPPER RIDGE COVERS 
THE REMAINDER OF THE ERN ATLC E OF 38W ANCHORED ON AN UPPER HIGH 
CENTERED OVER WESTERN SAHARA. BROAD SURFACE RIDGE REMAINS OVER 
THE ATLC N OF 25N E OF 52W ANCHORED BY A 1030 MB HIGH N OF THE 
AZORES. A WEAK SURFACE RIDGE EXTENDS SW FROM BERMUDA NEAR 30N70W 
TO OVER THE NW BAHAMAS. 
$$
HUFFMAN