000 AXNT20 KNHC 251048 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT APR 25 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 1045 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 5N8W 2N14W CROSSING THE EQUATOR NEAR 21W EXTENDING TO 1S28W 2S36W AND INTO NE BRAZIL NEAR 4S42W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS S OF 5N BETWEEN 5W-12W. SCATTERED MODERATE CONVECTION IS FROM 1N-4N BETWEEN 14W-19W. SCATTERED MODERATE CONVECTION IS ALSO S OF 3N BETWEEN 21W-28W. SCATTERED MODERATE CONVECTION IS ALSO S OF 2N BETWEEN 34W-47W. ...DISCUSSION... GULF OF MEXICO... DEEP LAYER DRY AIR AND SW TO W FLOW ALOFT ARE PRESENT ACROSS MUCH OF THE GULF REGION. SUBSIDENCE ASSOCIATED WITH A 1026 MB SURFACE HIGH OVER N FLORIDA NEAR 30N83W AND A SURFACE RIDGE ACROSS THE N GULF ALONG 29N IS CURRENTLY RESULTING IN GENERALLY FAIR WEATHER CONDITIONS ACROSS MUCH OF THE GULF REGION. THE FLOW AROUND THE AFOREMENTIONED SURFACE HIGH AND SURFACE RIDGE IS RESULTING IN SE WINDS OF 20 TO 25 KT ACROSS PORTIONS OF THE NW GULF...WITH E WINDS OF 20 TO 25 KT OVER THE E GULF S OF 25N EXCEPT 25 TO 30 KT ACROSS THE STRAITS OF FLORIDA. DURING THE NEXT DAY...THE 1026 MB SURFACE HIGH OVER N FLORIDA NEAR 30N83W IS FORECAST TO DISSIPATE. HOWEVER...THE SURFACE RIDGE ALONG 29N IS FORECAST TO DRIFT NE OF THE GULF REGION AND STRENGTHEN DURING THE NEXT DAY...WITH FRESH TO STRONG E TO SE SURFACE WINDS ACROSS THE GULF THROUGH TUESDAY. THESE WINDS WILL ADVECT LOW LEVEL MOISTURE ACROSS THE GULF REGION. INCREASING INSTABILITY OVER THE NW GULF WILL RESULT IN SCATTERED THUNDERSTORMS NEAR THE TEXAS COAST THROUGH SUNDAY. CARIBBEAN SEA... A 1031 MB SURFACE HIGH OVER THE W ATLC NEAR 33N70W IS MAINTAINING FRESH TO STRONG TRADE WINDS ACROSS THE CARIBBEAN SEA. THE STRONGEST WINDS ARE FOUND NEAR THE COAST OF COLOMBIA...WHERE NE TO E SURFACE WINDS UP TO 30 KT ARE OCCURRING. A BROAD UPPER LEVEL RIDGE IS PRESENT ACROSS THE CARIBBEAN SEA. ATMOSPHERIC STABILITY ASSOCIATED WITH THIS RIDGE IS RESULTING IN GENERALLY FAIR WEATHER CONDITIONS ACROSS MUCH OF THE CARIBBEAN. HOWEVER...THE TRADE WINDS ARE ADVECTING POCKETS OF LOW LEVEL MOISTURE WITH ISOLATED SHOWERS WESTWARD ACROSS THE CARIBBEAN. THE GREATEST CONCENTRATION OF THESE SHOWERS IS FROM 15N-18N BETWEEN 63W-74W. ALSO...UPPER LEVEL MOISTURE AND HIGH LEVEL CLOUDS CONTINUE TO STREAM NORTHEASTWARD ACROSS THE WESTERN CARIBBEAN...WITH UPPER LEVEL DIVERGENCE SUPPORTING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS OVER THE GULF OF HONDURAS S OF 18N W OF 87W INCLUDING S BELIZE AND NE GUATEMALA. ATLANTIC OCEAN... A DEEP LAYER TROUGH OVER THE WESTERN AND CENTRAL ATLC IS ASSOCIATED WITH A SURFACE COLD FRONT THAT EXTENDS FROM NE OF THE DISCUSSION AREA TO 32N55W TO 28N62W...A SURFACE STATIONARY FRONT THAT EXTENDS FROM 28N62W TO 26N70W...AND A SURFACE WARM FRONT THAT EXTENDS FROM 26N70W TO SW OF THE BAHAMAS NEAR 23N77W. LOW LEVEL CONVERGENCE IS RESULTING IN SCATTERED SHOWERS WITHIN 60 NM EITHER SIDE OF THESE FRONTS. THIS ACTIVITY IS ALSO BEING SUPPORTED BY UPPER LEVEL DIVERGENCE IN THE NE QUADRANT OF A 75-85 KT UPPER LEVEL WIND SPEED MAXIMUM OVER THE SW NORTH ATLC. TO THE W OF THE FRONTS...DEEP LAYER DRY AIR AND SUBSIDENCE ASSOCIATED WITH A 1031 MB SURFACE HIGH NEAR 33N70W ARE RESULTING IN GENERALLY FAIR WEATHER CONDITIONS. FARTHER TO THE E...SUBSIDENCE IN THE VICINITY OF A SURFACE RIDGE IS RESULTING IN GENERALLY FAIR WEATHER CONDITIONS ACROSS MUCH OF THE CENTRAL AND E ATLC. HOWEVER...ATMOSPHERIC INSTABILITY AND UPPER LEVEL DIVERGENCE IN THE VICINITY OF A SHARP UPPER LEVEL TROUGH WITH AN AXIS EXTENDING FROM 4N44W TO 19N37W TO 32N23W TO NE OF THE DISCUSSION AREA IS RESULTING IN SCATTERED SHOWERS N OF 23N BETWEEN 25W-33W. ACROSS THE TROPICAL ATLC...AN UPPER LEVEL RIDGE IS PRESENT WITH AN AXIS EXTENDING FROM 10N14W TO 4N25W TO 1N39W. UPPER LEVEL DIVERGENCE IN THE VICINITY OF THIS UPPER LEVEL RIDGE IS ENHANCING THE CONVECTION ASSOCIATED WITH THE ITCZ. $$ COHEN