000 AGXX40 KNHC 271843 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 243 PM EDT WED APR 27 2016 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W...AND THE SW N ATLANTIC INCLUDING THE BAHAMAS. MODEL PREFERENCE: PREVIOUS OFFICIAL FORECAST BLENDED WITH LATEST GFS/ECMWF FOR WINDS. MAINLY BLEND OF LATEST GFS AND WW3 FOR WAVES. HIGH CONFIDENCE. A SURFACE RIDGE AXIS EXTENDS ACROSS THE EASTERN AND CENTRAL NORTH GULF COAST FROM HIGH PRESSURE CENTERED OVER THE ATLC. LOW PRESSURE IS INLAND OVER MEXICO AND THE CENTRAL UNITED STATES WITH A THUNDERSTORM COMPLEX MARCHING EASTWARD OVER THE NORTHERN GULF COAST. THE SURFACE RIDGING IS FORECAST TO REMAIN IN TACT ACROSS THE NORTHERN GULF THROUGH THE PERIOD WITH A WEAK HIGH CENTER DEVELOPING OVER THE NE GULF BY FRI. MAINLY MODERATE SE WINDS ARE OVER THE GULF TODAY. A THERMAL TROUGH DEVELOPING EACH EVENING OVER THE YUCATAN AND PROPAGATING TO THE W TO NW WILL HELP SUPPORT FRESH TO STRONG SE WINDS THU AND FRI NIGHTS. PRESSURE FALLS OVER THE WESTERN MEXICO COAST NEAR AND INLAND OF VERA CRUZ ARE FORECAST BY THE MODELS FRI AND SAT. THIS WILL TIGHTEN THE PRESSURE GRADIENT OVER THE GULF OF MEXICO BETWEEN THE HIGH OVER THE NE GULF AND THE LOWER PRESSURES OVER MEXICO. THE RESULT WILL BE INCREASING SE WINDS TO FRESH TO STRONG OVER THE WESTERN GULF THU NIGHT AND FRI. SEAS WILL BUILD TO 8 FT OVER PORTIONS OF THE WESTERN GULF FRI THROUGH SAT. THE CONVECTION OVER THE NORTHERN GULF WILL LIKELY PERSIST INTO TONIGHT AS THE SHORTWAVE ENERGY SUPPORTING IT CONTINUES TO SLIDE EASTWARD. A SUBSEQUENT SURFACE BOUNDARY IS FORECAST TO REMAIN OVER THE NORTHERN GULF COAST THROUGH FRI WITH MODELS FORECASTING CHANCES FOR CONVECTION NEAR THE COAST THROUGH THAT TIME. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: PREVIOUS OFFICIAL FORECAST BLENDED WITH LATEST GFS/ECMWF FOR WINDS. MAINLY BLEND OF LATEST GFS AND WW3 FOR WAVES. HIGH CONFIDENCE. A WEAK RIDGE N OF THE AREA AND BROAD LOW PRESSURE OVER NORTHERN SOUTH AMERICA CONTINUE ACROSS THE REGION. MODELS ARE FORECASTING FOR THIS GENERAL PATTERN TO CONTINUE FOR THE NEXT SEVERAL DAYS WITH MODERATE TRADES PREVAILING OVER MUCH OF THE AREA. THE LONE EXCEPTION APPEARS TO BE A LOCAL INCREASE IN PRESSURE GRADIENT ALONG THE NORTHERN COAST OF HONDURAS THU NIGHT THROUGH FRI WHICH WILL SUPPORT LOCALLY FRESH TO STRONG EASTERLY WINDS WITHIN 90 NM OF THE HONDURAS COAST. THE MAIN FEATURE OVER THE BASIN DURING THE FORECAST PERIOD IS A SURFACE TROUGH EXTENDING FROM HAITI TO THE N CENTRAL CARIBBEAN AND TROUGHING CURRENTLY EXTENDING FROM THE DOMINICAN REPUBLIC OVER THE ATLC. MODELS ARE FORECASTING THE SURFACE TROUGHS TO DRIFT WESTWARD OVER THE NEXT COUPLE OF DAYS WHILE SUPPORTING PERIODS OF SHOWERS AND ISOLATED CONVECTION OVER THE N AND NE CARIBBEAN. THE TROUGHS ARE FORECAST TO AMPLIFY AND MERGE BY SAT..WHICH COULD SUPPORT UNSETTLED WEATHER OVER A LARGE PORTION OF THE EASTERN HALF OF THE CARIBBEAN OVER THE WEEKEND. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: PREVIOUS OFFICIAL FORECAST BLENDED WITH LATEST GFS/ECMWF FOR WINDS. MAINLY BLEND OF LATEST GFS AND WW3 FOR WAVES. HIGH CONFIDENCE. THE TAIL END OF A STATIONARY FRONT OVER THE CENTRAL ATLANTIC EXTENDS OVER THE EASTERN ZONES AND THEN TRANSITIONS TO A SURFACE TROUGH TO THE DOMINICAN REPUBLIC. WEAK RIDGING DOMINATES THE REMAINDER OF THE AREA TO THE NORTH. THE SURFACE TROUGH WILL SLOWLY DRIFT WESTWARD OVER THE NEXT COUPLE OF DAYS WHILE BECOMING MORE NE/SW ORIENTED. ENHANCED SHOWER ACTIVITY AND ISOLATED CONVECTION WILL REMAIN LIKELY IN THE VICINITY OF THIS TROUGH THROUGH FRI. MAINLY GENTLE TO MODERATE E TO SE WINDS ARE OCCURRING OVER THE AREA TODAY WITH MODERATE S TO SW WINDS OVER THE NW CORNER. A TROUGH AND WEAK COLD FRONT MOVING OFF THE UNITED STATES EAST COAST FRI WILL BREAK DOWN THE RIDGE AND MAY EXTEND AS FAR S AS 28N WITH A BRIEF PERIOD OF W-NW MODERATE TO FRESH WINDS IN NW WATERS FRI AND FRI NIGHT. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANE WARNINGS.GOV/MARINE $$ .FORECASTER LATTO. NATIONAL HURRICANE CENTER.