000 AXNT20 KNHC 141738 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT APR 14 2012 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1730 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE IVORY COAST NEAR 4N7W TO 1N17W...WHERE THE ITCZ CONTINUES ALONG 1N30W TO THE COAST OF BRAZIL NEAR 2S43W. SCATTERED TO NUMEROUS STRONG CONVECTIVE PRECIPITATION IS NOTICED S OF 5N BETWEEN 30W-50W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL RIDGE MOVES ACROSS THE GULF BRINGING DRY AIR AND STRONG SUBSIDENCE ALOFT TO THE DISCUSSION AREA. THIS UPPER LEVEL FEATURE IS ANCHORED BY A 1029 MB CENTERED OFF THE COAST OF THE CAROLINAS. THE SURFACE RIDGE AXIS ASSOCIATED TO THIS HIGH PRESSURE SYSTEM EXTENDS SW INTO THE AREA...AND TOGETHER WITH A DEVELOPING LOW PRESSURE SYSTEM OVER THE GREAT PLAINS...IS GENERATING A MODERATE E-W PRESSURE GRADIENT OVER THE GULF WITH 15-25 KT ESE WINDS ACROSS THE BASIN...OCCASIONALLY GUSTING TO 30 KT NEAR THE COASTAL WATERS OF TEXAS WHERE THE GRADIENT IS THE MOST CONSTRICTED. SHORT RANGE COMPUTER MODELS SUGGEST THE PRESSURE GRADIENT IS FORECAST TO STRENGTHEN...WITH SE WINDS INCREASING TODAY INTO SUNDAY AFTERNOON. THIS GRADIENT WILL BEGIN TO RELAX SLIGHTLY ON MONDAY. SCATTERED MODERATE TO HEAVY SHOWERS WILL MOVE THROUGH THE STRAITS OF FLORIDA INTO THE FAR ERN BASIN OVER THE NEXT HOUR OR SO. CARIBBEAN SEA... MODERATE TO STRONG SUBSIDENCE AND DRY AIR ALOFT COVERS A GREAT PORTION OF THE DISCUSSION AREA THIS AFTERNOON. THIS IS KEEPING MOST OF THE AREA UNDER FAIR WEATHER CONDITIONS WITH A FEW ISOLATED SHOWERS DOTTING THE BASIN. HOWEVER...THE SRN EXTENSION OF A COLD FRONT ENTERED THE FAR N CENTRAL BASIN A FEW HOURS AGO ADVECTING MODERATE TO HEAVY SHOWERS AND ISOLATED THUNDERSTORMS TO THE COASTAL WATERS BETWEEN PUERTO RICO AND HISPANIOLA N OF 17N BETWEEN 66W-75W. SIMILAR CONVECTION IS NOTICED OVER THE E AND NRN COASTAL WATERS OF JAMAICA LIKELY ASSOCIATED TO DAY-TIME HEATING...INSTABILITY...AND OROGRAPHIC EFFECTS. OTHERWISE... TRADEWIND FLOW OF 10-15 KTS IS REPORTED ACROSS THE AREA...WITH STRONGER NE FLOW FILTERING THROUGH THE WINDWARD AND MONA PASSAGES THROUGH SUNDAY. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH CONTINUES TO EXPAND ACROSS THE WRN ATLC THIS AFTERNOON. WATER VAPOR IMAGERY SHOWS A VIGOROUS SHORTWAVE EMBEDDED AT THE BASE OF THE UPPER TROUGH SUPPORTING A COLD FRONT THAT EXTENDS SSW INTO THE DISCUSSION AREA ALONG 32N51W 22N60W INTO THE FAR N CENTRAL CARIBBEAN SEA ALONG THE MONA PASSAGE. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS WITHIN 80-120 NM AHEAD OF THE COLD FRONT WHERE LOW LEVEL CONVERGENCE AND UPPER LEVEL DIFFLUENCE IS MAXIMIZED. A REGION OF SIMILAR CONVECTION IS FOUND W OF THE CENTRAL BAHAMAS MOVING INTO THE STRAITS OF FLORIDA. COMPUTER MODELS SUGGEST THE FRONT WILL CONTINUE TO TRACK E OVER THE NEXT 24 HOURS LEAVING FRESH TO STRONG NORTHERLY WINDS IN ITS WAKE. FAIR WEATHER CONDITIONS ARE FOUND ELSEWHERE AHEAD OF THE FRONTAL CONVECTION...ASSOCIATED TO A STRONG SURFACE RIDGE ANCHORED BY A 1031 MB HIGH CENTERED OVER THE AZORES. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA