000 AGXX40 KNHC 110817 CCA MIMATS MARINE WEATHER DISCUSSION...CORRECTED NWS NATIONAL HURRICANE CENTER MIAMI FL 359 AM EDT WED MAY 11 2016 CORRECTED SW N ATLC AND BAHAMAS SECTION 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. ...GULF OF MEXICO... MODEL PREFERENCE: 00Z GFS BLEND WITH PREVIOUS OFFICIAL FORECAST FOR WINDS. FOR WAVEHEIGHTS USED BLEND OF 00Z MWW3 WITH PREVIOUS OFFICIAL FORECAST. HIGH CONFIDENCE. THE LATEST SYNOPTIC ANALYSIS HAS HIGH PRES RIDGING EXTENDING FROM THE WRN ATLC WESTWARD ACROSS THE NRN GULF TO NEAR 93W. BUOY OBSERVATIONS AND PARTIAL ASCAT DATA SHOW SE TO S MODERATE FLOW THROUGHOUT...WITH THE EXCEPTION OF THE WATERS SURROUNDING THE NRN YUCATAN PENINSULA AND N TO 22.5N BETWEEN 88W-91W WHERE THE 0348 UTC ASCAT PASS PICKED UP ON NE-E WINDS OF 20-25 KT. THESE WINDS ARE FORECAST TO DIMINISH TO 15-20 KT LATER THIS MORNING. THE BUOYS ALONG WITH RECENT ALTIMETER PASSES SHOW SEAS IN THE RANGE OF 4-6 FT...EXCEPT FOR LOWER SEAS OF 2-3 FT E OF A LINE FROM NEAR THE BIG BEND AREA OF FL TO THE GULF SIDE OF THE LOWER FL KEYS. HIGHER SEAS OF 5-7 FT ARE IN THE STRAITS OF FL WHERE A PERSISTENT E-SE 20 KT WIND FLOW CONTINUES THERE. THE 5-7 FT SEAS SEAS ARE ABOUT 2 FT BELOW MWW3 GUIDANCE SO ADJUSTED THEM TOWARDS NWPS AND MWW3 MEAN ENSEMBLE GUIDANCE. THEY ARE FORECAST TO SLOWLY SUBSIDE TO 4-6 FT TONIGHT...AND TO 2-4 FT BY LATE THU AS WINDS THROUGH THE STRAITS BEGIN TO DIMINISH. LITTLE IN THE WAY OF CHANGES ARE IN STORE WITH THIS FORECAST. THE HIGH PRES RIDGING ACROSS THE NRN GULF IS FORECAST BY THE MODELS TO WEAKEN AND SHIFT E OF AREA THU NIGHT AS A WEAK COLD FRONT APPROACHES EASTERN TEXAS. THE COLD FRONT WILL MOVE ACROSS THE NW GULF EARLY ON FRI...THEN QUICKLY EXIT THE GULF FRI NIGHT. WEAK HIGH PRES WILL BUILD IN BEHIND THE FRONT THROUGH SAT NIGHT WITH A HIGH CENTER TO BE CENTERED OVER THE CENTRAL GULF. THE HIGH CENTER WILL SHIFT TO THE FAR EASTERN GULF BY LATE SUN WITH GENTLE TO MODERATE SE FLOW ACROSS THE WESTERN AND CENTRAL WATERS AND MOSTLY GENTLE N-NE WINDS OVER THE ERN GULF EARLY ON SUN...SHIFTING TO NE-E SUN AFTERNOON. SEAS WILL BE ON THE LOW SIDE THU THROUGH SUN NIGHT. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: 00Z GFS BLEND WITH PREVIOUS FORECAST FOR WINDS. FOR WAVEHEIGHTS USED A BLEND OF 00Z MWW3 WITH PREVIOUS OFFICIAL FORECAST. HIGH CONFIDENCE. SATELLITE IMAGERY SHOWS A LARGE SWATH OF DEEP MOISTURE WITH SCATTERED SHOWERS AND ISOLATED TSTMS CONFINED BETWEEN 66W-75W ...ALL UNDER A LARGE AREA OF UPPER LEVEL DIFFLUENCE TO THE E OF A VERY SHARP UPPER UPPER TROUGH THAT STRETCHES FROM JUST W OF HISPANIOLA SSW TO JUST NW OF COLOMBIA AND TO ACROSS ERN PANAMA. LATEST AND CURRENT BUOY OBSERVATIONS INDICATE GENTLE TO MODERATE TRADES THROUGHOUT THE CARIBBEAN. MODERATE NE-E TRADES ARE ACROSS THE TROPICAL N ATLC. THE OBSERVATIONS REVEAL SEAS IN THE 5-6 FT RANGE E OF 81W...EXCEPT FOR A POCKET OF 6-7 FT SEAS IN THE CENTRAL CARIBBEAN FROM 12N-16N BETWEEN 73W-78W...AND LOWER SEAS OF 3-5 FT W OF 81W. LOWER SEAS OF 1-3 FT ARE IN THE WRN CARIBBEAN SEA WITHIN 60 NM S OF CUBA...AND ALSO SW OF A LINE FROM SRN BELIZE TO 15N82W TO 09N80W. SEAS OF 6-8 FT IN THE TROPICAL N ATLC ARE DUE TO DECAYING NE-E SWELL THROUGH THOSE WATERS. THESE SEAS ARE FORECAST TO SUBSIDE TO 5-6 FT THU. WEAK HIGH PRES WILL REMAIN N OF THE AREA THROUGH THU WITH THE RESULTANT PRES GRADIENT SUPPORTING MAINLY MODERATE TRADES THROUGHOUT. FRESH NE-E WINDS WILL BEGIN IN THE SW CARIBBEAN ALONG THE COAST OF COLOMBIA FROM 11.5N TO 12.5N BETWEEN 73.5W-75.5W EARLY THIS EVENING UNDER A SLIGHTLY TIGHTER PRES GRADIENT. THESE WINDS ARE FORECAST TO DIMINISH TO 15-20 KT EARLY THU AFTERNOON... THEN PULSE BACK UP AGAIN TO THE FRESH RANGE THU EVENING INTO LATE THU NIGHT BEFORE DIMINISHING BACK TO 15-20 THU AFTERNOON. THE PULSING TREND WILL REPEAT EACH NIGHT THEREAFTER THROUGH SUN NIGHT WITH THE AREAL COVERAGE EXPANDING EASTWARD INTO THE ERN PORTION OF ZONE AMZ033. SEAS WITH THESE WINDS ARE EXPECTED TO REMAIN JUST BELOW 8 FT THROUGH THU...THEN BUILD TO 8 FT THU NIGHT AND TO A HIGHER RANGE OF 8-10 FT LATE SUN NIGHT OVER MUCH OF THE CENTRAL AND ERN PORTIONS OF THE SW GULF ZONE AMZ031 WITH 8 FT SEAS IN THE WRN PART OF ZONE AMZ033 AT THAT TIME. ...SW N ATLANTIC INCLUDING THE BAHAMAS...CORRECTED MODEL PREFERENCE: 00Z GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST FOR WINDS. FOR WAVEHEIGHTS USED BLEND OF 00Z MWW3 WITH PREVIOUS OFFICIAL FORECAST. HIGH CONFIDENCE. THE PRELIMINARY 06Z SURFACE ANALYSIS HAS WHAT WAS FORMERLY A WEAKENING STATIONARY FRONT NOW A TROUGH THAT EXTENDS FROM A PSN NEAR 30N66W SSW TO 26N69W TO JUST E OF THE SE BAHAMAS. PSN WAS MAINLY BASED ON THE ASCAT 0206Z PASS. A 1025 MB HIGH CENTER IS JUST N OF THE FORECAST WATERS NEAR 32N74W WITH A RIDGE EXTENDING WSW TO ACROSS NRN FL. ANOTHER RIDGE IS JUST E OF THE FAR NE WATERS OF THE AREA. CURRENT BUOY ALONG WITH THE 0206 ASCAT PASS DEPICT MODERATE NE-E WINDS S OF 25N W OF THE TROUGH...AND GENTLE SE-S WINDS NE-E WINDS N OF 25N W OF THE TROUGH EXCEPT FOR MODERATE SE-S WINDS OVER THE FAR NW WATERS. GENTLE TO MODERATE E WINDS ARE TO THE E OF THE TROUGH...EXCEPT FOR SE-S WINDS N OF 27N. OBSERVED SEA STATE IS THAT OF SEAS IN THE RANGE OF 4-6 FT E OF THE BAHAMAS...EXCEPT FOR A POCKET OF 5-7 FT S OF 23N E OF 66W. W AND SW OF THE BAHAMAS SEAS ARE IN THE 1-2 FT RANGE...EXCEPT FOR HIGHER SEAS OF 5-7 FT IN THE STRAITS OF FL. SEAS OF 3-4 FT ARE N OF THE BAHAMAS W OF 77W. THE FORECAST WILL HAVE LITTLE IN THE WAY OF CHANGES FROM PREVIOUS ONES AS WIND/WAVE MODEL GUIDANCE USED IN THE NDFD GRIDS CONTINUES TO RELATIVELY MATCH WELL WITH BUOY...SHIP AND ALTIMETER REPORTS. THE ONLY EXCEPTION IS IN THE STRAITS OF FL WHERE SEAS ARE THERE ARE ADJUSTED ABOUT 2 FT HIGHER THAN THE DETERMINISTIC GFS MWW3 OUTPUT USING GUIDANCE FROM THE NWPS TAFB WAVE OUTPUT...AND THE MWW3 MEAN ENSEMBLE GUIDANCE. THE TROUGH WILL CONTINUE TO MOVE WESTWARD...AND PASS ACROSS THE BAHAMAS THROUGH THU. SOME WEAK SIGNATURE OF THE TROUGH IS EXPECTED TO REACH THE WATERS BETWEEN THE BAHAMAS AND S FL ON FRI AS A WEAK COLD FRONT APPROACHES THE SE U.S. BY LATE FRI. THE FRONT WILL MOVE ACROSS THE FAR WRN WATERS SAT AND EARLY SAT NIGHT. IT APPEARS THAT THE SRN PORTION OF THE FRONT WILL HANG BACK AS A TROUGH OVER CENTRAL AND S FL SAT NIGHT INTO SUN...WHILE THE COLD FRONT PORTION CONTINUES EASTWARD OVER THE WATERS N AND NE OF THE BAHAMAS. THE FRONT IS FORECAST TO BE PRECEDED BY MODERATE SW WINDS OVER THE NW WATERS LATE FRI NIGHT. THESE WINDS THEN SHIFT E ACROSS THE NRN AND ERN PORTIONS OF THE BASIN AS THE FRONT PRESSES EASTWARD. NLY WINDS BEHIND THE FRONT UNDER A WEAK PRES PATTERN ARE FORECAST TO BE IN THE GENTLE CATEGORY. SEAS ARE FORECAST TO BE LOW...IN THE RANGE OF ABOUT 2-4 FT WITH THE WEAK FRONT. THE HIGHEST SEAS WILL BE FOUND OVER THE SE PORTION WHERE A LONG ELY FETCH THERE IS EXPECTED TO KEEP SEAS IN THE 5-6 FT RANGE THU THROUGH SUN NIGHT. WITH THE ADDED IMPETUS FROM SHORTWAVE ENERGY MOVING OVER THE NW WATERS FRI NIGHT THROUGH SAT AND ACROSS THE CENTRAL AND NE WATERS SAT NIGHT INTO SUN. THIS COMBINED WITH THE COLD FRONT ALONG WITH A MOIST AND UNSTABLE AIR MASS PRESENT OVER THE BASIN SHOULD BE CONDUCIVE ENOUGH FOR SCATTERED SHOWER AND TSTM ACTIVITY TO FIRE UP ALONG THE FRONT. SIMILAR ACTIVITY IS MOST PROBABLE WITH THE TROUGH PORTION OVER CENTRAL S FL AND NEARBY WATERS ON SAT. SOME OF THE SHOWER AND TSTMS MAY CONTAIN STRONG GUSTY WINDS AND FREQUENT LIGHTNING STRIKES. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS II COLLABORATION CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 AGUIRRE. NATIONAL HURRICANE CENTER.