000 AXNT20 KNHC 120000 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2350 UTC... ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 7N12W 4N20W 2N30W 2N40W INTO NORTHEAST COAST OF BRAZIL NEAR 1.5N50W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE WITHIN 200 NM BOTH SIDES OF THE ITCZ BETWEEN 30W-42W. AN AREA OF MODERATE TO STRONG CONVECTION IS FROM 3N-7N BETWEEN 17W-20W. ...DISCUSSION... GULF OF MEXICO... THE WEATHER ACROSS THE GOLF CONTINUES TO BE AFFECTED BY AN UNSTABLE ATMOSPHERE AFTER THE PASSAGE OF AN UPPER LEVEL SHORTWAVE...CURRENTLY OVER THE NORTHERN BAHAMAS. THIS FEATURE HAS LEFT MODERATE CONVECTION FROM 20N TO 28N BETWEEN 89W AND 98W. THE MOST ACTIVE WEATHER IS OCCURRING OVER THE SOUTHERN FLORIDA PENINSULA SOUTH OF 27N...DUE TO REMNANTS OF A FRONTAL BOUNDARY TRIGGERING CONVECTION IN THIS REGION. THIS BOUNDARY IS ANALYZED ENTERING THE FLORIDA KEYS NEAR 25N80W CONTINUING WESTWARD ALONG 25N83W TO 25N85W. MODERATE TO HEAVY SHOWERS AND POSSIBLE THUNDERSTORMS ARE WITHIN 70 NM NORTH OF THIS LINE. STRONG SUBSIDENCE IS OVER THE NORTHERN GULF NORTH OF 27N...WITH ALMOST CLEAR SKIES IN THIS REGION. COMPUTER MODELS PROJECT LITTLE CHANGE OVER THE NEXT 24 HOURS. THEREFORE...EXPECT LINGERING CONVECTION SOUTH OF 27N EAST OF 87W. CARIBBEAN SEA... STRONG SUBSIDENCE AND DRY AIR ALOFT DOMINATE THE ENTIRE BASIN...SUPPRESSING DEEP CONVECTION FROM DEVELOPING. HOWEVER...AN UPPER LEVEL SHORTWAVE IS MOVING NORTH OF THE DISCUSSION AREA ACROSS THE NORTHERN BAHAMAS. THIS FEATURE IS TRIGGERING SHOWERS WITH POSSIBLE THUNDERSTORMS ACROSS CUBA. AN AREA OF SCATTER SHOWERS IS ENTERING THE FAR EAST BASIN EAST OF 66W AFFECTING THE LESSER ANTILLES FROM 11N TO 17N. LOW LEVEL MOISTURE REMAINS ACROSS THE NORTHERN BASIN NORTH OF 16 PRODUCING SCATTERED SHOWERS OVER HISPANIOLA...PUERTO RICO..AND JAMAICA. MARINE OBSERVATIONS SHOW 10-20 KT EASTERLY TRADE WINDS ACROSS THE CARIBBEAN WITH THE STRONGEST WINDS ALONG THE COAST OF COLOMBIA. 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 NORTHERN PANAMA AND COSTA RICA. OVER THE NEXT 24 HOURS LOOK FOR CONVECTION TO CONTINUE TO DEVELOP OVER THE NORTH BASIN NORTH OF 16N...AND THE EASTERN BASIN EAST OF 65W. ATLANTIC OCEAN... A COLD FRONT ENTERS THE WESTERN ATLANTIC NEAR 32N60W CONTINUING SOUTHWEST TO 28N67W...WHERE IT CONTINUES AS A LINE OF CONVERGING WINDS THROUGH THE NORTHERN BAHAMAS AND FLORIDA STRAIGHTS. A WEAKENING UPPER LEVEL SHORTWAVE OVER THE NORTHERN BAHAMAS IS SUPPORTING THIS FRONTAL BOUNDARY. THE CONVECTION RELATED TO THIS SYSTEM COVERS FROM 23N TO 32N WEST OF 61W. TO THE EAST OF THE FRONT...A STRONG 1027 MB HIGH IS OVER THE CENTRAL ATLANTIC NEAR 36N45W. FURTHER EAST INTO THE EASTERN ATLANTIC...A COLD FRONT ENTERS THE REGION NEAR 32N18W AND CONTINUES SOUTHWEST ALONG 25N22W 23N30W 23N37W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 50 NM ON EITHER SIDE OF THE FRONT. THE UPPER SUPPORT FOR THIS FRONT IS AN ELONGATED UPPER LEVEL WAVE NORTH OF 30N FROM THE CANARY ISLANDS TO 40W. AN AREA OF SCATTER SHOWERS IS ENTERING THE FAR EAST CARIBBEAN AFFECTING THE LESSER ANTILLES FROM 10N TO 20N WEST OF 50W. ELSEWHERE ACROSS THE DISCUSSION AREA...DRY STABLE AIR ALOFT IS OBSERVED ON WATER VAPOR IMAGERY...SUPPRESSING ANY DEEP CONVECTION FROM DEVELOPING. OVER THE NEXT 24 HOURS LOOK FOR THE WEST AND EASTERN FRONTS TO CONTINUE TO MOVE EASTWARD WITH CONVECTION. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA