000 AXNT20 KNHC 281719 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN MAR 28 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 LIBERIA NEAR 5N9W ALONG 4N20W 2N30W 1S40W TO THE NE BRAZIL COASTLINE NEAR 1S51W. A SMALL CLUSTER OF MODERATE/STRONG CONVECTION IS JUST INLAND OVER LIBERIA NEAR 5N9W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 1S-4N BETWEEN 42W-53W. ...DISCUSSION... GULF OF MEXICO... AS OF 28/1500 UTC...A COLD FRONT CONTINUES TO PUSH ACROSS THE GULF OF MEXICO ASSOCIATED WITH A SURFACE LOW PRESSURE SYSTEM OVER THE WRN OHIO VALLEY. THE FRONT ENTERS THE GULF JUST E OF MOBILE ALABAMA CONTINUING ALONG 26N91W 24N94W TO THE MEXICO COAST NEAR VERACRUZ AT 19N96W. ISOLATED SHOWERS ARE WITHIN 120 NM EITHER SIDE OF THE FRONT. SURFACE OBSERVATIONS INDICATE STRONG 20-30 KT NLY WINDS BEHIND THE FRONT. AN INVERTED SURFACE TROUGH LIES TO THE E OF THE FRONT EXTENDING FROM S OF PANAMA CITY FLORIDA TO THE YUCATAN PENINSULA ALONG 29N86W 26N88W 22N89W. NUMEROUS SHOWERS AND THUNDERSTORMS ARE E OF THE TROUGH FROM 25N-30N BETWEEN 82W-88W. THIS AREA OF ACTIVITY IS BEGINNING TO IMPACT THE NW SIDE OF THE FLORIDA PENINSULA. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE ALSO E OF THE TROUGH FROM 24N-25N BETWEEN 89W-91W. IN THE UPPER LEVELS...AN UPPER LEVEL TROUGH EXTENDING ACROSS THE MISSISSIPPI VALLEY SUPPORTS THE FRONTAL SYSTEM. HOWEVER...MAINLY ZONAL WLY FLOW ALOFT COVERS THE GULF OF MEXICO. MODELS INDICATE A MID-LEVEL SWLY JET ACROSS THE ERN GULF WHICH MAY BE ENHANCING THE LARGE AREA OF SHOWERS/THUNDERSTORMS AHEAD OF THE SURFACE TROUGH. EXPECT THE FRONTAL SYSTEM TO CONTINUE TO PUSH EWD ACROSS THE GULF WITH CONTINUED SHOWER ACTIVITY AHEAD OF IT. CARIBBEAN SEA... GENERALLY FAIR WEATHER CONTINUES TO COVER THE CARIBBEAN TODAY UNDER THE IMPACT OF DRY AIR AND SUBSIDENCE WITH MAINLY ZONAL WLY FLOW ALOFT. A FEW ISOLATED SHOWERS ARE NOTED OFF THE N NICARAGUA COAST FROM 13N-16N BETWEEN 82W-84W. A FEW POSSIBLE ISOLATED SHOWERS ARE ALSO E OF THE LESSER ANTILLES. A STRONG PRESSURE GRADIENT BETWEEN SURFACE HIGH PRESSURE ACROSS THE W ATLC AND LOW PRESSURE OVER NRN COLOMBIA CONTINUES TO MAINTAIN FRESH TO STRONG TRADEWINDS ACROSS MUCH OF THE BASIN WITH THE STRONGEST WINDS OFF THE N COAST OF COLOMBIA. EXPECT MOISTURE AND SHOWER ACTIVITY TO INCREASE OVER THE NW CARIBBEAN AS A COLD FRONT CURRENTLY OVER THE GULF OF MEXICO REACHES THE YUCATAN CHANNEL EARLY MON. ATLANTIC OCEAN... SURFACE RIDGING CONTINUES TO DOMINATE THE W ATLC ANCHORED BY A 1035 MB HIGH OVER NOVA SCOTIA KEEPING CONDITIONS FAIR. THE SURFACE RIDGE IS SUPPORTED BY AN UPPER LEVEL RIDGE ALONG 72W ACCOMPANIED BY DRY AIR ALOFT. HOWEVER...UPPER LEVEL MOISTURE BEGINS TO MAKE ITS WAY OVER NRN FLORIDA ASSOCIATED WITH A COLD FRONT IN THE GULF OF MEXICO. GALE FORCE WINDS ARE EXPECTED TO DEVELOP IN THE NEXT 24 HOURS AS THIS FRONT MOVES ACROSS FLORIDA AND INTO THE ATLC. FARTHER E...A COLD FRONT ENTERS THE CENTRAL ATLC FROM A 1007 MB LOW NEAR 36N51W. THE FRONT ENTERS THE DISCUSSION AREA NEAR 32N52W CONTINUING ALONG 26N56W 23N65W BECOMING A DYING STATIONARY FRONT TO THE SE BAHAMAS NEAR 23N74W. ISOLATED SHOWERS ARE WITHIN 75 NM AHEAD OF THE FRONT. A SURFACE TROUGH IS E OF THE FRONT ALONG 27N51W TO 20N54W. A FEW CLUSTERS OF ISOLATED SHOWERS ARE WITHIN 75 NM EITHER SIDE OF THE TROUGH. THIS FRONTAL SYSTEM IS SUPPORTED BY AN UPPER LEVEL TROUGH WITH AXIS EXTENDING FROM 39N54W TO 26N52W. DIFFLUENCE ALOFT TO THE E SIDE OF THIS UPPER TROUGH IS ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 26N BETWEEN 45W-51W. ACROSS THE E ATLC...HIGH PRESSURE DOMINATES ANCHORED BY A 1023 MB HIGH NEAR 30N38W PROVIDING GENERALLY FAIR WEATHER. HOWEVER...A DYING FRONTAL BOUNDARY CREATES SMALL WEAKNESSES IN THE RIDGE ALONG 31N24W 24N34W. POSSIBLE ISOLATED SHOWERS ARE ALONG THE FRONTAL BOUNDARY. ALOFT...AN UPPER LEVEL RIDGE ALONG 37W SUPPORTS THE SURFACE RIDGE...WHILE A SHORTWAVE UPPER TROUGH TO THE E ALONG 30W SUPPORTS THE DYING FRONT. VISIBLE SATELLITE IMAGERY ALSO INDICATES A LARGE AREA OF DUST EXTENDING OFF THE COAST OF AFRICA E OF 33W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON