000 AGXX40 KNHC 240748 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 348 AM EDT SUN JUL 24 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. ...GULF OF MEXICO... MODEL PREFERENCE: FOR WINDS USED BLEND OF 00Z GFS WITH PREVIOUS OFFICIAL. FOR WAVEHEIGHTS USED BLEND OF 00Z MWW3 AND TAFB NWPS OUTPUT WITH PREVIOUS OFFICIAL FORECAST. HIGH CONFIDENCE. THE OVERALL SYNOPTIC HAS CHANGED VERY LITTLE OVER THE LAST SEVERAL DAYS WITH WEAK HIGH PRES RIDGING FROM THE ATLC CONTINUING TO EXTEND WESTWARD ACROSS THE NRN GULF WATERS WHILE AT THE UPPER LEVELS BROAD RIDGING COVERS THE JUST ABOUT THE ENTIRE GULF. A DIFFLUENT FLOW PATTERN ALOFT NOTED OVER THE ERN GULF IN COMBINATION WITH AMPLE DEEP MOISTURE PRESENT THERE IS AGAIN ALLOWING FOR SCATTERED SHOWERS AND ISOLATED TSTMS TO EXIST OVER MUCH OF THE ERN GULF WATERS. LATEST BUOY OBSERVATIONS AND RECENT ASCAT DATA INDICATE THAT THE PRES GRADIENT OVER THE AREA IS SUPPORTING GENERALLY GENTLE ELY WINDS...EXCEPT FOR THE FAR EASTERN PART OF BAY OF CAMPECHE ALONG THE YUCATAN PENINSULA WHERE WINDS ARE OF MODERATE INTENSITY FROM THE NE-E IN DIRECTION. THE BUOY OBSERVATIONS ALONG WITH RECENT ALTIMETER PASSES SHOW SEAS IN THE 1-3 FT RANGE. LITTLE IN THE WAY OF CHANGES ARE EXPECTED FOR THIS FORECAST PERIOD AS THE RIDGE WILL REMAIN RATHER WEAK THROUGH THE PERIOD WITH INTERMITTENT WEAK 1018-1019 MB HIGH CELLS FORMING ON THE RIDGE IN THE EASTERN GULF NEAR 27N85W. THE NRN EXTENSION OF A TROPICAL WAVE CURRENTLY APPROACHING THE YUCATAN PENINSULA WILL MOVE THROUGH THE BAY OF CAMPECHE MON THROUGH TUE. SOME SHOWER AND TSTM ACTIVITY CAN BE EXPECTED WITH THE WAVE. OTHERWISE...A THERMAL TROUGH IN THE YUCATAN PENINSULA WILL PUSH OFFSHORE INTO THE SW GULF EACH NIGHT THROUGH THE PERIOD ATTENDANT BY A BRIEF PERIOD OF FRESH N TO NE WINDS AND A SLIGHT INCREASE OF SEAS. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: FOR WINDS USED BLEND OF 00Z GFS WITH PREVIOUS OFFICIAL. FOR WAVEHEIGHTS USED BLEND OF 00Z MWW3 AND TAFB NWPS OUTPUT WITH PREVIOUS OFFICIAL FORECAST. HIGH CONFIDENCE. THE PRES GRADIENT BETWEEN HIGH PRES ACROSS THE CENTRAL ATLC AND LOWER PRES IN NRN PORTIONS OF S AMERICA AND THE SW CARIBBEAN IS MAINTAINING FRESH TO STRONG ELY WINDS IN THE SOUTH CENTRAL CARIBBEAN SEA...INCLUDING GULF OF VENEZUELA. THESE WINDS ARE FORECAST TO DIMINISH IN COVERAGE THIS AFTERNOON...AND CHANGE LITTLE THROUGH MON BEFORE THEY BEGIN TO EXPAND IN COVERAGE MON NIGHT THROUGH THU AS HIGH PRES OVER THE WRN ATLC SHIFTS S. PRESENT SEAS OF 8 FT IN THE S CENTRAL CARIBBEAN WILL BUILD TO 8-10 FT WED...WITH THE GENERAL AREA EXPANDING TO THE N CENTRAL CARIBBEAN SEA ON THU. A NARROW SWATH OF STRONG E WINDS JUST S AND SE OF HISPANIOLA WILL PULSE THROUGH WED. THESE WINDS THEN MERGE WITH THE EXPANDING AREA OF FRESH TO STRONG WINDS FROM THE S CENTRAL CARIBBEAN ON WED NIGHT. A TROPICAL WAVE WELL E OF THE TROPICAL N ATLC ZONES IN THE E ATLC IS FORECAST TO ENTER THE ERN PORTION OF THE TROPICAL N ATLC MON EVENING ...THEN MOVE ACROSS THE LESSER ANTILLES EARLY ON TUE AND ACROSS THE CENTRAL CARIBBEAN WED THROUGH THU NIGHT. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: FOR WINDS USED BLEND OF 00Z GFS WITH PREVIOUS OFFICIAL. FOR WAVEHEIGHTS USED BLEND OF 00Z MWW3 AND TAFB NWPS OUTPUT WITH PREVIOUS OFFICIAL FORECAST. HIGH CONFIDENCE. A SURFACE TROUGH EXTENDS FROM NEAR 30N76W TO THE NW BAHAMAS AND TO JUST N OF N CENTRAL CUBA...WHILE WEAK HIGH PRES IS PRESENT ELSEWHERE. AN UPPER LOW HAS DROPPED S TO NEAR 26N79W. PLENTY OF ATMOSPHERIC MOISTURE AND INSTABILITY HAS LED TO SCATTERED SHOWER AND TSTM ACTIVITY OVER THE WATERS BETWEEN THE BAHAMAS AND S FL. SCATTERED TSTMS ARE ALSO OBSERVED OVER THE N CENTRAL PORTION OF ZONE AMZ115 IN ASSOCIATION WITH A SHORTWAVE UPPER TROUGH MOVING ACROSS THOSE WATERS. LATEST SYNOPTIC ANALYSIS REVEALS A RATHER WEAK PRES GRADIENT THROUGHOUT WITH LIGHT TO GENTLE E-SE WINDS ACROSS MUCH OF THE BASIN...EXCEPT FOR THE N CENTRAL PORTION WHERE WINDS ARE LIGHT MAINLY S-SW IN DIRECTION. BOTH BUOY AND ALTIMETER DATA SHOW SEAS IN THE RANGE OF 2-4 FT E OF THE BAHAMAS...AND 0-1 FT SW OF THE BAHAMAS...AND ALSO N OF 27N W OF 80W. A SMALL POCKET OF SEAS IN THE 4-5 FT RANGE ARE NOTED BETWEEN THE SE BAHAMAS AND HISPANIOLA. THE SEAS E OF THE BAHAMAS ARE FORECAST TO INCREASE SLIGHTLY TO THE S OF ABOUT 25N BEGINNING ON MON AS AN E SWELL BECOMES RATHER PERSISTENT. THE AFOREMENTIONED UPPER LOW IS FORECAST TO GRADUALLY WEAKEN TO AN INVERTED TROUGH AS IT MOVES ACROSS S FL TODAY...AND TO THE ERN GULF OF MEXICO TONIGHT AND MON. MID/UPPER LEVEL RIDGING WILL REPLACE THE LOW OVER THE NW AND N CENTRAL SECTIONS OF THE BASIN. AT THE SURFACE...RIDGING WILL SET UP ROUGHLY ALONG A PSN FROM 29N69W NW TO NE FL BY TUE NIGHT WITH A 1021 MB HIGH FORECAST TO BE NEAR 29N69W LATE ON MON. THIS HIGH WILL WEAKEN AS IT SHIFTS SSE THROUGH THU IN RESPONSE TO A FRONTAL TROUGH THAT BRUSHES THE FAR NE WATERS. THE FLOW PATTERN S OF THE RIDGE WILL BECOME E-SE WITH WINDS IN THE GENTLE TO MODERATE RANGE...EXCEPT FOR THE STRONGER PULSING E WINDS TO THE STRONG CATEGORY BETWEEN THE BAHAMAS AND HISPANIOLA. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS II COLLABORATION CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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.