000
AXNT20 KNHC 111059
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT MON MAY 11 2009

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1015 UTC.

...THE ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 5N9W 4N20W CROSSING THE EQUATOR 
NEAR 32W AND INTO NE BRAZIL NEAR 3S40W. ISOLATED MODERATE 
CONVECTION IS ALONG THE COAST OF W AFRICA FROM 3N-6N BETWEEN 
5W-7W. SIMILAR CONVECTION IS FROM 1N-4N BETWEEN 18W-23W...AND 
FROM 2N-4N BETWEEN 26W-28W. A LARGE CLUSTER OF SCATTERED 
MODERATE CONVECTION IS ALONG THE COAST OF NE BRAZIL FROM 3S-8S 
BETWEEN 34W-40W. 

...DISCUSSION...

GULF OF MEXICO...
AS OF 0900 UTC...A STATIONARY FRONT IS INLAND OVER THE N GULF 
STATES WITH CONVECTION. A 1019 MB HIGH IS OVER THE NE GULF OF 
MEXICO NEAR 28N84W. 5-10 KT ANTICYCLONIC WINDS ARE NOTED 
AROUND THE HIGH. THE REMAINDER OF THE GULF CONTINUES TO HAVE 
10-15 KT SOUTHERLY RETURN FLOW. FAIR WEATHER DOMINATES THE 
ENTIRE GULF OF MEXICO. IN THE UPPER LEVELS...ZONAL FLOW WITH 
STRONG SUBSIDENCE IS OVER THE ENTIRE GULF OF MEXICO CONTRIBUTING 
TO THE FAIR WEATHER. EXPECT...CONTINUED FAIR TO PARTLY CLOUDY 
SKIES WITH SE FLOW OVER THE GULF FOR THE NEXT 24 HOURS AS A 
FRONTAL SYSTEM TRAVERSES THE N GULF STATES. 

CARIBBEAN SEA...
FRESH TRADES CONTINUE OVER THE CARIBBEAN SEA WITH STRONGEST 
WINDS ALONG THE COAST OF N COLOMBIA. A LARGE AREA OF SCATTERED 
MODERATE TO ISOLATED STRONG CONVECTION IS INLAND OVER N COLOMBIA 
FROM 2N-9N BETWEEN 73W-80W. WIDELY SCATTERED MODERATE CONVECTION 
IS INLAND OVER PANAMA...AND COSTA RICA. ELSEWHERE...RAIN AND 
SHOWERS ARE OVER THE LEEWARD ISLANDS...PUERTO RICO...AND 
HISPANIOLA N OF 15N AND E OF 74W. IN THE UPPER LEVELS...AN UPPER 
LEVEL RIDGE IS PRODUCING SW-W FLOW OVER THE CARIBBEAN. 
CONSIDERABLE UPPER LEVEL MOISTURE IS OVER THE CARIBBEAN. 
EXPECT...LITTLE CHANGE OVER THE NEXT 24 HOURS.   

ATLANTIC OCEAN...
A LARGE 1024 MB HIGH IS OVER THE CENTRAL ATLANTIC NEAR 30N48W. A 
SURFACE RIDGE EXTENDS W TO N FLORIDA. SCATTERED SHOWERS ARE N OF 
PUERTO RICO AND THE LEEWARD ISLANDS FROM 19N-22N BETWEEN 
57W-70W. A DISSIPATING COLD FRONT IS OVER THE E ATLANTIC N OF 
THE CANARY ISLANDS ALONG 32N13W 29N18W 27N24W. SCATTERED SHOWERS 
ARE WITHIN 120 NM S OF THE FRONT. IN THE TROPICS...A SURFACE 
TROUGH IS E OF THE LESSER ANTILLES ALONG 19N56W 13N56W MOVING W. 
SCATTERED SHOWERS ARE WITHIN 90 NM OF THE TROUGH. IN THE UPPER 
LEVELS...AN UPPER LEVEL HIGH IS OVER THE W ATLANTIC NEAR 27N64W. 
A BROAD UPPER LEVEL TROUGH IS FURTHER E BETWEEN 20W-55W. IN THE 
TROPICS...A LARGE UPPER LEVEL HIGH IS CENTERED NEAR 6N36W WITH A 
RIDGE AXIS EXTENDING W TO 8N60W. EXPECT...THE COLD FRONT OVER 
THE E ATLANTIC TO DRIFT E OVER THE NEXT 24 HOURS WITH SHOWERS. 

$$
FORMOSA