000 AXNT20 KNHC 092317 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN MAY 09 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 2215 UTC... ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 7N26W TO 1N28W MOVING W 10-15 KT. THE WAVE LIES AHEAD OF AN AREA OF ENHANCED MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED STRONG CONVECTION IS FROM 4N-7N BETWEEN 23W-28W. TROPICAL WAVE IS ALONG 40W S OF 7N MOVING W 5 KT. THE WAVE REMAINS ILL-DEFINED WITH NO ASSOCIATED DEEP CONVECTION. TROPICAL WAVE IS ALONG 56W S OF 9N MOVING W NEAR 15 KT. WAVE LIES AHEAD OF A LARGE AREA OF ENHANCED MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 7N-10N BETWEEN 51W-58W. ENHANCED CONVECTION IS ALSO INLAND OVER SOUTH AMERICA. SCATTERED STRONG CONVECTION IS S OF 5N BETWEEN 50W-60W. ...THE ITCZ... ITCZ AXIS IS CENTERED FROM SIERRA LEONE NEAR 9N11W ALONG 5N20W 3N30W 5N40W INTO NE SOUTH AMERICA NEAR 4N54W. BESIDES AREAS ASSOCIATED WITH TROPICAL WAVES...A LARGE CLUSTER OF NUMEROUS STRONG CONVECTION IS INLAND OVER SIERRA LEONE AND LIBERIA FROM 7N-11N BETWEEN 9W-14W. THIS ACTIVITY MAY BE ASSOCIATED WITH THE NEXT TROPICAL WAVE. ISOLATED MODERATE/STRONG CONVECTION IS FROM 4N-7N BETWEEN 18W-22W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 6N-8N BETWEEN 44W-50W. ...DISCUSSION... GULF OF MEXICO... AS OF 2100 UTC...A COLD FRONT EXTENDS ACROSS S FLORIDA NEAR MIAMI ALONG 26N80W TO 25N87W BECOMING STATIONARY TO 27N92W AND RETREATING AS A WARM FRONT INTO CENTRAL TEXAS NEAR GALVESTON. THE FRONT IS SUPPORTED BY AN UPPER LEVEL TROUGH OVER THE W ATLC THAT EXTENDS INTO THE NW CARIBBEAN. NO SIGNIFICANT WEATHER IS ASSOCIATED WITH THE FRONT BESIDES ISOLATED SHOWERS ACROSS NE TEXAS AND LOUISIANA. A WEAK PRE-FRONTAL TROUGH EXTENDS THROUGH THE FLORIDA STRAIGHTS. A SECOND SURFACE TROUGH LINES THE MEXICO COAST FROM 22N97W TO 10N94W SUPPORTING LOW CLOUDS OFF THE NE COAST OF MEXICO. THE REMAINDER OF THE GULF OF MEXICO REMAINS CLEAR TONIGHT UNDER THE INFLUENCE OF A DRY AND STABLE AIRMASS AROUND AN UPPER LEVEL RIDGE EXTENDING FROM THE E PACIFIC S OF MEXICO. EXPECT THE WRN HALF OF THE FRONT TO CONTINUE TO LIFT N OUT OF THE AREA AS THE COLD FRONT GRADUALLY DISSIPATES AS IT MOVES OUT OF THE GULF. HIGH PRESSURE WILL BUILD SWD BEHIND THE FRONT. CARIBBEAN SEA... AN UPPER LEVEL TROUGH CONTINUES TO LIE OVER THE NW CARIBBEAN EXTENDING FROM HONDURAS ACROSS CENTRAL CUBA AND OVER THE FAR W ATLC. HOWEVER...IT IS ACCOMPANIED BY DRY AIR ALOFT KEEPING FAIR CONDITIONS ACROSS THE NW CARIBBEAN. A FEW ISOLATED SHOWERS/THUNDERSTORMS ARE POSSIBLE ACROSS THE SW CARIBBEAN AND CENTRAL AMERICA AROUND THE BASE OF THIS UPPER TROUGH AND NEAR LOW PRESSURE OVER NRN COLOMBIA. THE REMAINDER OF THE BASIN IS COVERED BY AN UPPER LEVEL RIDGE CENTERED N OF NE SOUTH AMERICA ACCOMPANIED BY SOME MODERATE UPPER LEVEL MOISTURE BEHIND DRAWN UP FROM THE E PACIFIC SUPPORTING A FEW HIGH CLOUDS. A SURFACE TROUGH EXTENDS ACROSS ERN HISPANIOLA FROM 22N66W TO 19N70W. ISOLATED SHOWERS ARE WITHIN 150 NM EITHER SIDE OF THE AXIS N OF 18N. ATLANTIC OCEAN... A COLD FRONT ENTERS THE FAR W ATLC NEAR 32N70W TO NEAR MIAMI FLORIDA AT 26N80W SUPPORTED BY AN UPPER LEVEL TROUGH EXTENDING FROM N OF MAINE SWD TO THE NW CARIBBEAN. MOST OF THE SHOWER ACTIVITY ASSOCIATED WITH THIS FRONT IS N OF THE AREA. A FEW ISOLATED SHOWERS ARE POSSIBLE WITHIN 30 NM EITHER SIDE OF THE FRONT N OF 29N. A WEAK 1018 MB SURFACE LOW IS N OF THE LEEWARD ISLANDS NEAR 26N62W WITH A SURFACE TROUGH EXTENDING FROM THE CENTER TO NEAR 23N63W. ISOLATED SHOWERS ARE WITHIN 75 NM N OF THE LOW CENTER AND E OF THE TROUGH. A SECOND SURFACE TROUGH EXTENDS FROM NEAR 22N66W TO 19N70W ACROSS ERN HISPANIOLA SUPPORTING ISOLATED SHOWERS WITHIN 150 NM EITHER SIDE OF THE AXIS. BOTH OF THESE AREAS ARE ASSOCIATED WITH ENHANCED MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. A SURFACE RIDGE DOMINATES THE CENTRAL ATLC ANCHORED BY A 1024 MB HIGH NEAR 32N50W SUPPORTED BY AN UPPER LEVEL RIDGE EXTENDING FROM NE SOUTH AMERICA TO NEAR 35N45W. AN UPPER LEVEL TROUGH COVERS THE E ATLC N OF THE CAPE VERDE ISLANDS CENTERED NE OF SPAIN SUPPORTING A SURFACE TROUGH...REMNANTS OF A FRONTAL BOUNDARY...EXTENDING FROM 30N14W ALONG 25N20W 22N28W. POSSIBLE ISOLATED SHOWERS ARE WITHIN 30 NM OF THE TROUGH. S OF THE TROUGH...FAIR WEATHER PREVAILS INFLUENCED BY AN UPPER LEVEL RIDGE COVERING THE TROPICAL ATLC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON