000 AXNT20 KNHC 090516 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT WED APR 09 2008 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND THE 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0345 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 5N8W 3N19W 1N31W CROSSING THE EQUATOR NEAR 36W TO 2S43W. SCATTERED STRONG CONVECTION IS FROM 2N-4N BETWEEN 8W-11W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE FROM 2N TO S OF THE EQUATOR BETWEEN 26W-31W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE ANCHORED IN THE E PACIFIC REGION COVERS MEXICO AND MOST OF GULF W OF 86W. THE STRONG SHORTWAVE UPPER TROUGH EXTENDS FROM THE W ATLC ACROSS FLORIDA NEAR LAKE OKEECHOBEE TO AN UPPER LOW IN THE FLORIDA STRAITS NEAR 24N81W THEN CONTINUES OVER THE NW CARIBBEAN. A DISSIPATING STATIONARY BOUNDARY EXTENDS THROUGH THE FLORIDA STRAITS ALONG 24N80W TO 25N84W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE S OF 26N E OF 86W THROUGH THE FLORIDA STRAITS AND OVER THE FLORIDA KEYS WITH THE HEAVIEST CONCENTRATION OF THUNDERSTORMS OVER W CUBA. STRONG SUBSIDENCE AND DRY AIR COVERS THE REMAINDER OF THE GULF WITH LOW CLOUDS BANKING IN THE W GULF W OF 95W TO INLAND OVER TEXAS AND NE MEXICO. AN UPPER TROUGH IS MOVING ACROSS THE UPPER MISSISSIPPI VALLEY EXTENDING A COLD FRONT THROUGH TEXAS. THIS FRONT IS NOT EXPECTED TO ENTER THE GULF BUT A SECOND REINFORCING COLD FRONT WILL MOVE OFF THE TEXAS COAST LATE FRI INTO SAT. CARIBBEAN SEA... UPPER SHORTWAVE TROUGH IN THE E GULF OF MEXICO EXTENDS OVER THE NW CARIBBEAN W OF A LINE FROM NE HONDURAS TO CENTRAL CUBA BUT DUE TO THE STRONG SUBSIDENCE AND DRY AIR ONLY SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS ARE ABLE TO FORM WITHIN CLOSE PROXIMITY OF THE UPPER LOW IN THE FLORIDA STRAITS...INLAND AND WITHIN 45 NM ALONG THE COAST OF W CUBA FROM 82W-84W. BROAD UPPER RIDGE COVERS THE REMAINDER OF THE CARIBBEAN EXTENDING FROM THE E/W UPPER RIDGE THAT COVERS THE TROPICS. MODERATE/STRONG E TRADE WINDS DOMINATE THE CARIBBEAN WITH THE STRONGEST WINDS ALONG THE COAST OF COLOMBIA AND ARE USHERING IN SOME LOW LEVEL ISOLATED SHOWERS N OF 16N FROM 63W-74W. UPPER LEVEL DIVERGENCE IS OVER PANAMA AND COSTA RICA GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS INLAND AND WITHIN 60 NM ALONG THE COASTLINE. OTHERWISE THE REMAINDER OF THE CARIBBEAN IS REMARKABLY CLEAR TONIGHT. ATLANTIC OCEAN... SHORTWAVE UPPER TROUGH THAT COVERS THE E GULF OF MEXICO EXTENDS OVER THE FAR W ATLC W OF 76W WITH A COLD FRONT ENTERING THE REGION NEAR 32N70W TO A WEAK 1014 MB LOW NEAR 28N74W CONTINUING S TO THE CENTRAL BAHAMAS NEAR 24N76W WHERE A DISSIPATING STATIONARY BOUNDARY EXTENDS THROUGH THE FLORIDA STRAITS INTO THE SE GULF OF MEXICO. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE FROM 26N TO THE COAST OF CUBA W OF 77W TO THE SE COAST OF FLORIDA AND INTO THE FLORIDA STRAITS. BROAD UPPER RIDGE COVERS THE REMAINDER OF THE W ATLC AND THE CENTRAL ATLC WITH THE MEAN AXIS ALONG 55W AND A WEAK 1019 MB HIGH NEAR 25N60W. BROAD UPPER TROUGH COVERS THE E ATLC N OF 26N BETWEEN 15W-40W WITH A COMPLEX FRONTAL SYSTEM N OF THE REGION. A COLD FRONT EXTENDS INTO THE REGION THROUGH 32N17W ALONG 23N24W TO 21N45W AND A DEVELOPING COLD FRONT...REINFORCING SURGE EXTENDS INTO THE REGION THROUGH 32N20W ALONG 29N30W THEN NW TO BEYOND 32N42W. A WEAK SURFACE RIDGE IS S OF THE UPPER TROUGH WITH A 1017 MB HIGH LOCATED NEAR 18N23W. BROAD E/W UPPER RIDGE COVERS THE TROPICS. $$ WALLACE