000 AXNT20 KNHC 051709 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT WED MAY 05 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... ...ITCZ... ITCZ AXIS IS CENTERED FROM N LIBERIA NEAR 7N11W ALONG 4N20W 3N30W 1N40W TO NE BRAZIL NEAR EQ51W. AN EMBEDDED SURFACE TROUGH IS FROM EQ-7N ALONG 31W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 2N-6N BETWEEN 9W-21W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 1N-3N BETWEEN 28W-30W...FROM 1N-6N BETWEEN 33W-37W...AND FROM 7N-10N BETWEEN 45W-48W. ...DISCUSSION... GULF OF MEXICO... AS OF 1500 UTC...A COLD FRONT EXTENDS ACROSS N FLORIDA FROM NEAR JACKSONVILLE THROUGH GAINESVILLE CONTINUING AS A STATIONARY FRONT INTO THE GULF OF MEXICO ALONG 29N83W 27N86W 27N91W. A SURFACE TROUGH IS S OF THE FRONT ALONG 27N87W 25N90W 21N91W. SURFACE CONVERGENCE NEAR THE FRONT COMBINED WITH UPPER DIFFLUENCE AROUND THE E SIDE OF A SHORTWAVE UPPER TROUGH EXTENDING INTO THE SE GULF SUPPORT SCATTERED SHOWERS/THUNDERSTORMS WITHIN 60 NM AHEAD OF THE FRONT E OF 85W. ISOLATED SHOWERS ARE POSSIBLE WITHIN 60 NM EITHER SIDE OF THE REMAINDER OF THE FRONTAL BOUNDARY AS WELL AS THE SURFACE TROUGH. SIGNIFICANT DRY AIR AND SUBSIDENCE ALOFT AROUND AN UPPER LEVEL HIGH OVER CENTRAL MEXICO KEEPING SURFACE CONDITIONS FAIR WITH MOSTLY CLEAR SKIES ACROSS THE REMAINDER OF THE BASIN TO EITHER SIDE OF THE FRONT. SURFACE RIDGING COVERS THE FAR SE GULF EXTENDING FROM HIGH PRESSURE IN THE W ATLC. WEAK SURFACE RIDGING IS ALSO W OF THE FRONT ANCHORED BY A 1015 MB HIGH S OF LOUISIANA NEAR 27N93W. EXPECT THE FRONT TO GRADUALLY DRIFT EWD AND WEAKEN OVER THE NEXT 24 HRS. CARIBBEAN SEA... CONDITIONS REMAIN FAIR ACROSS MUCH OF THE NW CARIBBEAN DUE TO THE INFLUENCE OF SIGNIFICANT DRY AIR ALOFT EXTENDING FROM THE GULF OF MEXICO. HOWEVER...A MID/UPPER LEVEL TROUGH CENTERED NEAR 17N82W IS SUPPORTING ISOLATED SHOWERS/THUNDERSTORMS FROM 17N-20N BETWEEN 77W-83W. THIS MID-UPPER LEVEL TROUGH IS DRAWING MOISTURE FROM THE E PACIFIC ACROSS THE CENTRAL CARIBBEAN SUPPORTING HIGH CLOUDS. ISOLATED SHOWERS/THUNDERSTORMS ARE ALSO ACROSS THE SW CARIBBEAN S OF 11N DUE TO SURFACE CONVERGENCE NEAR THE E PACIFIC ITCZ WHICH CROSSES OVER CENTRAL AMERICA ACROSS SRN COSTA RICA AND CONTINUES EWD TO NRN COLOMBIA. A SHEAR LINE EXTENDS FROM THE ATLC ACROSS THE LESSER ANTILLES ALONG 15N61W 14N65W 15N69W. WIND SPEED CONVERGENCE NEAR THE SHEAR AXIS IS ENHANCING ISOLATED SHOWERS WITHIN 30 NM EITHER SIDE OF THE AXIS. ATLANTIC OCEAN... A FRONTAL BOUNDARY AFFECTING NRN FLORIDA EXTENDS INTO THE FAR W ATLC FROM NEAR JACKSONVILLE TO 32N78W CONTINUING N OF THE AREA. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE E OF THE FRONT N OF 28N BETWEEN 74W-80W. THE REMAINDER OF THE W ATLC IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1020 MB HIGH NEAR 29N66W PROVIDING GENERALLY FAIR WEATHER ACROSS THE AREA. THE SURFACE RIDGE IS SUPPORTED BY AN UPPER LEVEL RIDGE CENTERED NEAR 26N57W. FARTHER E...A SURFACE TROUGH...REMNANTS OF A FRONT...EXTENDS ALONG 31N27W 24N36W. POSSIBLE ISOLATED SHOWERS ARE WITHIN 30 NM OF THE AXIS. A SHEAR LINE...REMNANTS OF THE SAME FRONTAL BOUNDARY... EXTENDS FROM 18N52W TO THE LESSER ANTILLES NEAR 15N61W. ISOLATED SHOWERS ARE WITHIN 75 NM N OF THE SHEAR AXIS. THE TROUGH AND SHEAR LINE ARE SUPPORTED BY A NARROW UPPER LEVEL TROUGH EXTENDING FROM 32N24W TO 10N57W. ACROSS THE E ATLC...AN UPPER LEVEL RIDGE IS CENTERED S OF THE CAPE VERDE ISLANDS NEAR 12N23W KEEPING CONDITIONS FAIR. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON