000 AXNT20 KNHC 191145 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT MAR 19 2011 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTION 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. ...ITCZ... THE ITCZ AXIS IS ALONG 7N11W 2N20W CROSSING THE EQUATOR AT 25W THEN CONTINUES ALONG 2S30W INTO NE BRAZIL NEAR 5S38W. SCATTERED MODERATE TO STRONG CONVECTION IS INDICATED FROM THE EQUATOR TO 2N BETWEEN 18W AND 28W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS NOTED FROM 2N TO 5N BETWEEN 8W AND 15W. ISOLATED MODERATE CONVECTION IS NOTED WITHIN 45 NM EITHER SIDE OF A LINE FROM 2N30W TO 3N37W. ...DISCUSSION... GULF OF MEXICO... A 1025 MB SURFACE HIGH PRESSURE LOCATED OVER THE NORTH CENTRAL GULF NEAR 28N88W DOMINATES MOST OF THE GULF OF MEXICO AND THE STATE OF FLORIDA PRODUCING FAIR WEATHER CONDITIONS...EXCEPT FOR OVERCAST LOW CLOUDS ALONG THE COAST OF MEXICO AND SE TEXAS. WINDS ARE LIGHT AND VARIABLE NEAR THE HIGH PRES CENTER...WITH MODERATE TO FRESH EASTERLY AND WINDS ON THE SOUTHERN PERIPHERY OF THE HIGH WITH SOUTHEASTERLY RETURN FLOW OVER THE WESTERN GULF WATERS. THE BAND OF TRANSVERSE HIGH CLOUDS NOTED EARLIER OVER THE SOUTHERN GULF HAS BECOME LESS DEFINED AS THE AREA MOVES SE INTO THE FAR NW CARIBBEAN. MODERATE TO STRONG SUBSIDENCE AND THE IMPLIED DRY AIR MASS IS SEEN N OF 25N INCLUDING THE GULF COAST STATES AND FLORIDA WHERE MILD AND DRY WEATHER CONDITIONS ARE EXPECTED TO CONTINUE THROUGH TODAY. THE SURFACE RIDGE IS FORECAST TO REMAIN NEARLY STATIONARY OVER THE NEXT SEVERAL DAYS AND CONTINUE TO PROVIDE OVERALL STABLE WEATHER CONDITIONS. CARIBBEAN SEA... AN UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED IN THE TROPICAL ATLANTIC NEAR 7N32W EXTENDS A RIDGE OVER MOST OF THE CARIBBEAN WITH SW WINDS ALOFT OVER THE BASIN. MODERATE TO STRONG SUBSIDENCE IS ASSOCIATED WITH THIS RIDGE LIMITING THE DEVELOPMENT OF ANY DEEP CONVECTION. SHALLOW MOISTURE EMBEDDED IN THE TRADE WIND FLOW WILL CONTINUE TO AFFECT THE REGION GENERATING ISOLATED TO SCATTERED PASSING SHOWERS. A BAND OF LOW LEVEL CLOUDS WITH EMBEDDED SHOWERS IS NOTED WITHIN 120 NM OF THE COAST OF COLOMBIA. SURFACE HIGH PRES LOCATED OVER THE NE GULF AND PORTIONS OF THE SW NORTH ATLANTIC CONTINUES TO PRODUCE A LARGE AREA OF FRESH TO STRONG NE TRADES OVER MUCH OF THE CARIBBEAN WITH THE STRONGEST WINDS NEAR THE COAST OF COLOMBIA. A SHIP WITH CALL SIGN ZCDF4 REPORTED NE WINDS OF 25-30 KT WITHIN THE PAST HOUR. ANOTHER SHIP WITH CALL SIGN 5RDK2 REPORTED NE WINDS OF 25 KT. NE WINDS OF 2O KT CAN BE FOUND OVER THE NW CARIBBEAN AND JUST SOUTH OF DOMINICAN REPUBLIC. LOW LEVEL NE WINDS ARE BANKING CLOUDS OVER PANAMA AND COSTA RICA. THE SURFACE FLOW IS FORECAST TO REMAIN QUITE BRISK THROUGH THE WEEKEND AND INTO MON AS A STRONG HIGH PRES BUILDS OVER THE W ATLANTIC. ATLANTIC OCEAN... HIGH PRES AT THE SURFACE AND ALOFT DOMINATES THE WESTERN ATLC W OF 65W WITH MOSTLY FAIR WEATHER CONDITIONS. THE COMBINATION OF THIS HIGH AND GENERAL TROUGHINESS ALONG 60W IS RESULTING IN FRESH NE WINDS ACROSS THE SOUTHERN BAHAMAS AND THE GREATER ANTILLES. THESE WINDS ARE FORECAST TO PERSIST THROUGH SAT NIGHT...AND INCREASE LATER TODAY AND MON AS STRONG HIGH PRESSURE BUILDS IN FROM THE NORTH. SURFACE DATA AND A 0200 UTC ASCAT PASS INDICATED NE WINDS OF 20 KT NEAR THE SE BAHAMAS AND 25 KT WINDS IN THE WINDWARD PASSAGE. AN UPPER LEVEL TROUGH WITH AXIS EXTENDING FROM A SMALL BUT VIGOROUS UPPER-LEVEL LOW NEAR 29N59W TO 22N64W. THE UPPER LOW WAS SWEEPING TO THE ESE AT 10-15 KT. UPPER DIFFLUENCE AHEAD OF THE UPPER LEVEL TROUGH AND LOW IS AIDING IN THE DEVELOPMENT OF EXPANDING AREA OF DEEP LAYERED CLOUDINESS WITH SCATTERED SHOWERS AND TSTMS ALONG AND WITHIN 300 NM TO THE N OF A STATIONARY FRONT WHICH EXTENDED FROM 21N45W TO 25N50W TO A DEVELOPING 1012 MB LOW NEAR 25N54W. A 1014 MB LOW WAS LOCATED FURTHER NW NEAR 28N58W WITH A SURFACE TROUGH EXTENDING SWD THROUGH 25N58W TO 22N62W. ANOTHER SURFACE TROUGH EXTENDED FROM 21N58W TO 15N59W. FURTHER EAST...A STATIONARY CUT-OFF LOW IS NEAR 36N30W WITH A NEGATIVELY TILTED TROUGH EXTENDING S AND SE TO NEAR 24N23W. THIS UPPER LEVEL FEATURE IS PROVIDING MARGINAL SUPPORT FOR A SURFACE TROUGH THAT ENTERS THE DISCUSSION AREA NEAR 31N25W THEN CONTINUES SW TO 22N31W. A 1026 MB HIGH PRES SITUATED NEAR 34N43W IS BUILDING SE IN THE WAKE OF THE SURFACE TROUGH. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ COBB