000
AXNT20 KNHC 132340
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT MON APR 13 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2315 UTC.

...THE ITCZ...
THE ITCZ AXIS IS CENTERED ALONG 5N9W...CROSSING THE EQUATOR 
ALONG 22W TO NORTHEASTERN BRAZIL NEAR 3S42W. ISOLATED STRONG 
CONVECTION IS FROM 1N-3N BETWEEN 19W-22W. SCATTERED MODERATE TO 
ISOLATED STRONG CONVECTION IS FROM 1N-3N BETWEEN 26W-30W. 
SIMILAR CONVECTION IS FROM 2N-4S BETWEEN 36W-43W.

...DISCUSSION...

THE GULF OF MEXICO...
AS OF 2100 UTC...A COLD FRONT HAS MOVED OFF THE COAST OF TEXAS 
ALONG 30N93W 26N97W. A PRE-FRONTAL TROUGH E OF THE COLD FRONT 
EXTENDS FROM 29N91W 24N95W AND S ALONG 95W TO A 1007 MB 
DISSIPATING LOW NEAR 21N95W. AHEAD OF THE TROUGH...SCATTERED 
MODERATE CONVECTION COVERS THE NE GULF OFF THE COAST OF ALABAMA 
AND THE FLORIDA PANHANDLE EXTENDING NE ALONG THE SE U.S. 
SEABOARD. CENTRAL AND S FLORIDA ALONG WITH THE SE GULF OF MEXICO 
HAS 15-20 KT WINDS WITH FAIR WEATHER. ISOLATED RAIN SHOWERS ARE 
OVER THE BAY OF CAMPECHE. IN THE UPPER LEVELS...AN UPPER LEVEL 
TROUGH IS OVER THE W GULF W OF 90W. AN UPPER LEVEL RIDGE IS OVER 
THE E GULF. CONSIDERABLE UPPER LEVEL MOISTURE IS OVER THE E GULF 
BETWEEN 82W-91W. EXPECT THE COLD FRONT TO MOVE WESTWARD WITH 
CONVECTION CONTINUING.       

THE CARIBBEAN SEA...
FRESH TRADEWINDS ARE OVER THE CARIBBEAN AND CENTRAL AMERICA WITH 
STRONGEST WINDS ALONG THE COAST OF N COLOMBIA. SCATTERED SHOWERS 
ARE OVER THE WINDWARD ISLANDS E OF 63W. SCATTERED SHOWERS ARE 
ALSO OVER THE LEEWARD ISLANDS N OF 17N AND E OF 66W. THE 
REMAINDER OF THE CARIBBEAN AND CENTRAL AMERICA HAS MOSTLY FAIR 
WEATHER. IN THE UPPER LEVELS...BROAD RIDGE IS OVER THE CARIBBEAN 
WITH STRONG SUBSIDENCE. EXPECT LITTLE CHANGE OVER THE NEXT 24 
HOURS. 
 
THE ATLANTIC OCEAN...
THE TAIL END OF A COLD FRONT CLIPS THE W ATLANTIC NEAR 32N65W 
AND IS EXPECTED TO MOVE NE AND REMAIN N OF 32N. E OF THIS COLD 
FRONT A SECOND COLD FRONT EXTENDS FROM 32N54W 28N58W 25N65W. 
SCATTERED SHOWERS ARE 180 NM E OF THE FRONT N OF 29N. A 1034 MB 
HIGH IS OVER THE E ATLANTIC NEAR 41N36W. A RIDGE AXIS EXTENDS S 
TO 20N35W. IN THE UPPER LEVELS...A RIDGE/TROUGH/RIDGE PATTERN IS 
PRESENT WITH THE FIRST RIDGE OVER THE W ATLANTIC W OF 65W. AN 
UPPER LEVEL TROUGH IS OVER THE CENTRAL ATLANTIC N OF 20N BETWEEN 
45W-65W. ANOTHER LARGE UPPER LEVEL RIDGE IS OVER THE E ATLANTIC 
E OF 45W. AN UPPER LEVEL HIGH IS OVER THE TROPICAL ATLANTIC NEAR 
9N15W. A RIDGE AXIS EXTENDS W TO 7N60W. 

$$
WALTON/HUFFMAN