000 AXNT20 KNHC 112358 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE MAR 11 2014 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2230 UTC. ...SPECIAL FEATURES... A COLD FRONT IS FORECAST TO MOVE INTO THE NORTHWESTERN GULF OF MEXICO EARLY WEDNESDAY. WINDS ARE EXPECTED TO GUST TO GALE FORCE BEHIND THE FRONT NW OF A LINE FROM 29N91W TO 24N97W THROUGH WED AFTERNOON UNTIL SUSTAINED GALE FORCE WINDS MATERIALIZE BEHIND THE FRONT ALONG THE COAST OF VERACRUZ FROM 20N TO 24N W OF 95W EARLY WED EVENING. GALE FORCE WINDS ARE FORECAST TO DIMINISH BY SUNRISE THU. THE SAME COLD FRONT IS FORECAST TO INDUCE GALE FORCE WINDS IN THE SOUTHWEST NORTH ATLC. WEST TO NORTHWEST WINDS BEHIND THE FRONT N OF 29N WILL PICK UP TO MINIMAL GALE FORCE BY EARLY THU MORNING AND CONTINUE N OF 29N WITHIN 240 NM WEST OF THE FRONT AS IT MOVES TO 32N71W TO THE STRAITS OF FLORIDA SUNRISE THU... DIMINISHING BELOW GALE FORCE BY THU AFTERNOON. SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS ON BOTH OF THESE GALE WIND EVENTS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 07N11W TO 01N16W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 01N16W TO THE EQUATOR AT 18W. ISOLATED MODERATE CONVECTION IS S OF 06N E OF 27W TO THE ITCZ/MONSOON TROUGH. ...DISCUSSION... GULF OF MEXICO... A MIDDLE LEVEL LOW IS NOTED ON WATER VAPOR IMAGERY OVER NORTHERN LOUISIANA AND IS DRAGGING A WEAKENING TROUGH EASTWARD OVER THE NORTH CENTRAL GULF OF MEXICO. THIS SYSTEM REFLECTS A TROUGH AT THE SURFACE FROM SOUTHERN LOUISIANA INTO THE WEST CENTRAL GULF. WIDESPREAD SHOWERS AND THUNDERSTORMS ARE OCCURRING N OF 24N BETWEEN 84W AND 92W INCLUDING INLAND PORTIONS OF COASTAL MISSISSIPPI...ALABAMA AND FLORIDA. THE LOW IS EXPECTED TO CONTINUE ON A N-NE TRACK AND GRADUALLY BECOME EMBEDDED WITHIN SOUTHWESTERLY FLOW AT THE SURFACE AHEAD OF THE NEXT COLD FRONT EXPECTED TO EMERGE OFF THE TEXAS AND LOUISIANA COAST BY EARLY WEDNESDAY. SEE THE SPECIAL FEATURES SECTION FOR DETAILS ON THE GALE CONDITIONS EXPECTED BEHIND THE FRONT. CARIBBEAN SEA... A STATIONARY FRONT IS ANALYZED FROM THE CENTRAL ATLC TO EASTERN PUERTO RICO WHERE ISOLATED SHOWERS ASSOCIATED WITH THE BOUNDARY ARE OCCURRING. ELSEWHERE...ONLY A FEW AREAS OF ISOLATED SHOWERS CAN BE FOUND WITH THE MOST CONCENTRATED AREA OF SHOWERS NOTED BETWEEN HAITI AND JAMAICA. THE OVERALL LACK OF SHOWER ACTIVITY IS DUE TO UPPER LEVEL RIDGING EXTENDING FROM THE BAHAMAS THROUGH EASTERN CUBA TO NW VENEZUELA NEAR 11N70W. THE UPPER LEVEL RIDGE IS GENERALLY PROVIDING STABILITY AND DRY AIR OVER THE BASIN. WINDS AT THE SURFACE ARE RELATIVELY WEAK ACROSS THE CARIBBEAN...WITH A 1017 MB HIGH IN THE SW NORTH ATLC EAST OF THE BAHAMAS NEAR 26N69W DRIVING THE FLOW. WINDS HAVE SHIFTED SOUTHEASTERLY IN THE NW CARIBBEAN ON THE WEST SIDE OF THE HIGH...WHILE THE STRONGEST TRADE WINDS ARE EXPECTED TO OCCUR CLOSE TO THE COAST OF COLOMBIA IN THE EARLY MORNING HOURS WHEN THE PRESSURE GRADIENT IS THE STRONGEST. THE HIGH TO THE NORTH OF THE BASIN WILL SHIFT E-NE AHEAD OF A COLD FRONT EXPECTED TO MOVE INTO THE GULF OF MEXICO WEDNESDAY. THE STATIONARY BOUNDARY NORTHEAST OF PUERTO RICO WILL DISSIPATE AS A RESULT. THE COLD FRONT WILL BRING AN INCREASED CHANCE OF SHOWERS AND THUNDERSTORMS TO THE NW CARIBBEAN BY LATE WED AFTERNOON AND CONTINUING INTO THU. THE FRONT IS EXPECTED TO REACH FROM CENTRAL CUBA TO THE GULF OF HONDURAS BY THU AFTERNOON. ...HISPANIOLA... THE AFOREMENTIONED WEAK WINDS OVER THE CARIBBEAN HAVE ALLOWED A SEABREEZE TO PUSH INLAND FROM THE COAST OVER HISPANIOLA. VISIBLE SATELLITE IMAGERY SHOWS CLOUDS ACCUMULATED WHERE THE SEABREEZE HAS MET THE WINDWARD SLOPES. PRECIPITABLE WATER IMAGERY SHOWS DRIER AIR IN PLACE OVER THE DOMINICAN REPUBLIC N OF THE MIDDLE LEVEL TROUGH SUPPORTING THE STATIONARY BOUNDARY NE OF PUERTO RICO COMPARED TO HAITI WHERE AN AREA OF SHOWERS IS PASSING TO THE SOUTH. THE CHANCE OF RAIN SHOULD DIMINISH SOMEWHAT TOMORROW AS THIS MIDDLE LEVEL TROUGH DISSIPATES...BUT WILL INCREASE ON THU AS THE COLD FRONT MOVES INTO THE NORTHWESTERN CARIBBEAN AND MOISTURE AHEAD OF IT BECOMES MORE PLENTIFUL. ATLANTIC OCEAN... THE SW NORTH ATLC REGION REMAINS FAIRLY TRANQUIL THIS EVENING. WEAK 1017 MB HIGH PRES REMAINS EAST OF THE BAHAMAS NEAR 26N69W AND A STATIONARY FRONT STRETCHES FROM 32N37W TO EASTERN PUERTO RICO. SCATTERED SHOWERS CAN GENERALLY BE FOUND WITHIN 120 NM EITHER SIDE OF THE TROUGH E OF 50W AND MORE ISOLATED SHOWERS ARE MAINLY WITHIN 120 NM S OF THE FRONT W OF 50W. A BROAD MIDDLE TO UPPER LEVEL TROUGH EVIDENT ON WATER VAPOR IMAGERY OVER THE CENTRAL ATLC IS SUPPORTING THE STATIONARY FRONT AT THE SURFACE. A 120 KT UPPER JET IS PUSHING INTO THE SOUTHERN PORTION OF THE TROUGH. THIS IS ALLOWING THE SURFACE STATIONARY FRONT TO BEGIN TO WEAKEN W OF 50W. THE BROAD TROUGH ALOFT WILL BE SQUEEZED EASTWARD AS A NEW BROAD TROUGH AMPLIFIES OVER THE CENTRAL U.S. AND PROMOTES RIDGING AHEAD OF IT OVER THE WESTERN AND CENTRAL ATLC WED AND THU. THE LINGERING ENERGY ASSOCIATED WITH THE STATIONARY FRONT WILL WEAKEN AND BECOME CAUGHT IN THE SOUTHERLY FLOW AHEAD OF THE NEW TROUGH ON THU. THIS TROUGH WILL SEND A STRONG COLD FRONT INTO THE SW NORTH ATLC EARLY THU...WITH GALE FORCE WINDS EXPECTED BEHIND THE FRONT. SEE THE SPECIAL FEATURES SECTION FOR DETAILS ON THIS GALE EVENT. OTHERWISE...THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE FROM 32N27W TO 20N40W TO SAINT LUCIA. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ SCHAUER