000 AXNT20 KNHC 111718 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN APR 11 2010 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC... ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 7N9W 3N20W 1N47W INTO NE BRAZIL SOUTH AMERICA NEAR 1N50W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE WITHIN 200 NM BOTH SIDES OF THE ITCZ BETWEEN 12W-23W AND WITHIN 60 NM OF LINE FROM ACROSS THE EQUATOR NEAR 3W TO 2N7W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 3N-7N BETWEEN 46W-49W. CLUSTERS OF SIMILAR CONVECTION ARE FROM 3N W OF 48W TO INLAND OVER SOUTH AMERICA. ...DISCUSSION... GULF OF MEXICO... A SURFACE RIDGE DOMINATES THE GULF ANCHORED BY A 1030 MB HIGH OFF THE NORTH CAROLINA COAST WITH A WEAKNESS ALONG A SURFACE TROUGH THAT EXTENDS FROM THE W ATLC ACROSS THE FLORIDA PENINSULA BETWEEN MELBOURNE TO FORT MYERS INTO THE GULF JUST W OF KEY WEST TO 24N83W. A FAST MOVING SHORTWAVE UPPER TROUGH IS SUPPORTING THIS SURFACE TROUGH EXTENDING FROM NEAR TALLAHASSEE FLORIDA TO THE NW CUBAN COAST NEAR HAVANA. THE REMAINDER OF THE GULF IS DOMINATED BY NEAR ZONAL WESTERLY FLOW ALOFT. BROKEN/OVERCAST MULTILAYERED CLOUDS WITH SCATTERED SHOWERS/THUNDERSTORMS ARE WITHIN 150 NM OF LINE FROM ACROSS FLORIDA NEAR NAPLES TO 25N86W THEN WITHIN 200 NM OF LINE FROM 24N90W TO OVER TEXAS/NE MEXICO NEAR THE BORDER. A SWATH OF STRONG SUBSIDENCE IS OVER THE CENTRAL GULF WITHIN 90/120 NM OF LINE FROM W CUBA NEAR 23N84W TO OVER LOUISIANA...THUS THE LACK OF SHOWERS THERE. THE SHORT WAVE UPPER TROUGH AND SURFACE TROUGH WILL MOVE OUT OF THE GULF LATER THIS EVENING AS THE SURFACE RIDGE ANCHORED N OF AREA WILL STRENGTHEN ON MON AND INCREASE EASTERLY WINDS THROUGH WED. CARIBBEAN SEA... SURFACE RIDGE OVER THE W/CENTRAL ATLC INTO THE GULF OF MEXICO IS MAINTAINING FRESH TO STRONG EASTERLY TRADE WINDS ACROSS THE CARIBBEAN WITH THE STRONGEST WINDS ALONG THE COAST OF COLOMBIA. NEAR ZONAL WESTERLY WINDS ALOFT WITH STRONG SUBSIDENCE AND DRY AIR ALOFT DOMINATE THE ENTIRE BASIN. LOW LEVEL MOISTURE REMAINS ACROSS THE CARIBBEAN AND COUPLED WITH THE TRADE WINDS ARE PRODUCING SCATTERED SHOWERS DOTTING THE CARIBBEAN E OF 77W. THE TRADE WINDS ARE ALSO BANKING LOW LEVEL CLOUDS WITH SCATTERED SHOWERS IN THE SW CARIBBEAN INLAND ALONG THE MOUNTAINS AND WITHIN 45 NM ALONG THE COAST OF W PANAMA AND COSTA RICA W OF 81W. ATLANTIC OCEAN... A SURFACE RIDGE COVERS THE W AND CENTRAL ATLC ANCHORED BY A 1030 MB HIGH JUST OFF THE COAST OF NORTH CAROLINA AND A 1031 MB HIGH IS OVER THE CENTRAL ATLC NEAR 37N46W. A SURFACE TROUGH FORMS A WEAKNESS INT HE SURFACE RIDGE EXTENDING FROM 30N79W ACROSS THE FLORIDA PENINSULA NEAR MELBOURNE INTO THE GULF OF MEXICO. A COLD FRONT BRIDGES THE SURFACE RIDGE ENTERING THE REGION NEAR 32N61W TO 29N66W BECOMING STATIONARY TO 28N71W. THE UPPER SUPPORT FOR THIS FRONT IS AN UPPER TROUGH N OF 22N FROM 54W-65W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE COVER THE W ATLC N OF 25N W OF 70W TO OVER FLORIDA. A COLD FRONT ENTERS THE E ATLC NEAR 32N22W EXTENDING ALONG 29N24W TO 25N33W BECOMING STATIONARY TO 25N39W. ISOLATED SHOWERS ARE WITHIN 90 NM SE OF THE FRONT. THE UPPER SUPPORT FOR THIS FRONT IS N OF 26N FROM THE CANARY ISLANDS TO 36W AND THE UPPER LOW JUST S OF THE AZORES. THE EASTERLY TRADE WINDS OF THE CARIBBEAN ARE ALSO IN THE TROPICAL ATLC MAINLY N OF 15N W OF 53W AND ARE GENERATING SCATTERED LOW LEVEL SHOWERS FROM 13N-19N W OF 54W ACROSS THE LESSER ANTILLES. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALLACE