000 AXNT20 KNHC 141800 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT WED APR 14 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 1645 UTC... ...THE ITCZ... THE ITCZ AXIS IS CENTERED FROM SRN LIBERIA NEAR 5N8W ALONG 6N20W 4N30W 4N40W 6N50W AND INTO NE SOUTH AMERICA NEAR 5N56W. NUMEROUS STRONG CONVECTION IS INLAND OVER AFRICA FROM 4N-9N BETWEEN 6W-10W. SIMILAR ACTIVITY IS FROM 1N-6N BETWEEN 11W-18W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 3N-6N BETWEEN 24W-35W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 1N-7N BETWEEN 40W-53W. SCATTERED MODERATE/STRONG CONVECTION IS ALSO FROM 6N-10N BETWEEN 58W-60W. ...DISCUSSION... THE GULF OF MEXICO... A SURFACE RIDGE BUILDS ACROSS THE GULF OF MEXICO FROM A 1037 MB HIGH N OF THE GREAT LAKES PROVIDING GENERALLY FAIR WEATHER ACROSS THE N CENTRAL AND ERN GULF. HOWEVER...A SHORTWAVE UPPER LEVEL TROUGH OVER THE WRN GULF IS ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS IN THE S CENTRAL GULF FROM 21N-25N BETWEEN 85W-93W...AND ACROSS THE SRN TIP OF TEXAS FROM 24N-28N W OF 93W. AN UPPER LEVEL RIDGE COVERS THE REMAINDER OF THE BASIN WITH AXIS EXTENDING DOWN THE FLORIDA PENINSULA. WATER VAPOR IMAGERY INDICATES SIGNIFICANTLY DRY AIR ACROSS THE NE GULF SUPPORTING CLEAR SKIES ACROSS THIS AREA. SURFACE OBSERVATIONS INDICATE MAINLY E WINDS OF 20-25 KTS ACROSS THE GULF. EXPECT THE SURFACE RIDGE TO REMAIN WHILE SHOWERS/THUNDERSTORMS CONTINUE ACROSS THE CENTRAL GULF. THE CARIBBEAN SEA... MUCH OF THE CARIBBEAN IS EXPERIENCING GENERALLY FAIR WEATHER TODAY INFLUENCED BY AN UPPER LEVEL RIDGE ACROSS THE BASIN EXTENDING FROM THE FLORIDA PENINSULA. HOWEVER...ISOLATED SHOWERS ARE NOTED ACROSS THE NW CARIBBEAN N OF 19N W OF 82W DUE TO THE APPROACH OF A SHORTWAVE UPPER LEVEL TROUGH ACROSS THE WRN GULF. ISOLATED SHOWERS ARE ALSO OFF THE COAST OF PANAMA AND NRN COLOMBIA NEAR A 1009 MB LOW OVER NRN COLOMBIA NEAR 8N74W. A SURFACE TROUGH EXTENDS FROM THE CENTRAL ATLC ACROSS PUERTO RICO TO NEAR 18N67W. SCATTERED SHOWERS ARE N OF 17N BETWEEN 65W-68W. TOTAL PRECIPITABLE WATER IMAGERY INDICATES A LARGE AREA OF ENHANCED LOW-LEVEL MOISTURE THAT HAS REMAINED ACROSS THE LEEWARD ISLANDS FOR THE PAST SEVERAL DAYS SUPPORTING CONTINUED SHOWER ACTIVITY OVER THE AREA. IN FACT...GUADELOUPE REPORTED 2.85 INCHES OF RAIN FOR THE PAST 24 HR TOTAL. A WEAK PRESSURE GRADIENT IS PROVIDING MODERATE TRADEWINDS ACROSS MUCH OF THE BASIN. EXPECT THE SURFACE TROUGH ACROSS PUERTO RICO TO DRIFT NE...WHILE ENHANCED MOISTURE CONTINUES TO IMPACT THE LEEWARD ISLANDS. THE ATLANTIC OCEAN... THE FAR W ATLC IS INFLUENCED BY A SURFACE RIDGE BUILDING FROM THE N PROVIDING GENERALLY FAIR WEATHER W OF 67W. THE SURFACE RIDGE IS SUPPORTED BY AN UPPER LEVEL RIDGE EXTENDING DOWN THE FLORIDA PENINSULA. A DEEP LAYER TROUGH IMPACTS THE W CENTRAL ATLC ENHANCING A LARGE AREA OF SHOWER ACTIVITY. THE ASSOCIATED SURFACE TROUGH EXTENDS FROM 31N61W TO CENTRAL PUERTO RICO ALONG 25N64W TO 18N67W. MOST OF THE SHOWER ACTIVITY IS E OF THE TROUGH AXIS WITHIN 500 NM. MUCH OF THE ACTIVITY IS ENHANCED BY DIFFLUENT FLOW ALOFT TO THE E SIDE OF THE UPPER LEVEL TROUGH ALONG 63W. ANOTHER SURFACE TROUGH IS NOTED E OF THE LESSER ANTILLES FROM 18N51W TO 15N52W. ISOLATED SHOWERS ARE WITHIN 150 NM EITHER SIDE OF THE AXIS. AS MENTIONED IN THE CARIBBEAN SEA SECTION...THERE IS A LARGE AREA OF ENHANCED MOISTURE ASSOCIATED WITH THE DEEP LAYER TROUGH CONCENTRATED OVER THE LEEWARD ISLANDS. GUADELOUPE HAS ALREADY REPORTED A 24 HR PRECIPITATION TOTAL OF 2.85 INCHES. THIS AREA OF LOW-LEVEL MOISTURE IS EXPECTED TO CONTINUE IMPACTING THE LEEWARD ISLANDS FOR AT LEAST THE NEXT 24 HRS. FARTHER E...A WEAK SURFACE RIDGE BUILDS ACROSS THE REMAINDER OF THE CENTRAL ATLC BETWEEN 35W-50W PROVIDING FAIR WEATHER OVER THIS PORTION OF THE BASIN. THIS RIDGE IS SUPPORTED BY A NARROW UPPER LEVEL RIDGE ALONG 45W. ACROSS THE ERN ATLC...A PAIR OF SURFACE TROUGHS...REMNANTS OF FRONTAL BOUNDARIES REMAIN ASSOCIATED WITH A STATIONARY 993 MB LOW SW OF PORTUGAL NEAR 35N16W. ONE TROUGH AXIS EXTENDS ALONG 32N13W ACROSS THE CANARY ISLANDS TO 26N18W 22N29W. THE SECOND TROUGH EXTENDS ALONG 31N18W 27N25W 27N29W. POSSIBLE ISOLATED SHOWERS ARE WITHIN 30 NM EITHER SIDE OF BOTH TROUGH AXIS. THIS SYSTEM IS SUPPORTED BY AN UPPER LEVEL TROUGH CENTERED E OF THE AZORES ISLANDS NEAR 36N23W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON