000 AGXX40 KNHC 111714 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 114 PM EDT SAT JUL 11 2015 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: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. TAFB NWPS USED FOR WAVE HEIGHTS AND PRIMARY WAVE PERIOD. HIGH CONFIDENCE. MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL WHICH WAS A GFS/ECMWF BLEND. TAFB NWPS USED FOR SEAS HEIGHTS AND PRIMARY WAVE PERIOD WITH MANUAL ADJUSTMENTS TO MATCH OBSERVATIONS. HIGH CONFIDENCE. AN INVERTED THERMAL TROUGH IS EXPECTED TO DEVELOP EACH AFTERNOON OVER THE YUCATAN PENINSULA...AND THEN MOVE WNW ACROSS THE GULF WATERS S OF 23N BETWEEN 90-93W DURING THE EVENING THROUGH LATE NIGHT HOURS...REACHING ALONG 94-95W DURING THE EARLY DAYLIGHT HOURS...AND THEN DISSIPATE BY EARLY AFTERNOON. EXPECT A NE TO E 20-25 KT WIND SHIFT WITHIN ABOUT 120 NM OF THE TROUGH AXIS TONIGHT...THEN ONLY A 15-20 KT WIND SHIFT EXPECTED ALONG THE TROUGH THROUGH THU NIGHT. AN UPPER TROUGH EXTENDS W ACROSS THE FAR SE GULF OF MEXICO WITH A SLIGHT ENHANCEMENT OF CONVECTION OVER THE E GULF WATERS...SO ISOL TS DENOTED IN WEATHER GRIDS IN THAT AREA FOR THIS AFTERNOON...THEN THE MOISTURE IS EXPECTED TO REMAIN OVER THE FL PENINSULA INTO EARLY NEXT WEEK. OTHERWISE...A RIDGE EXTENDING SE FROM THE MS DELTA TO FL BAY THIS AFTERNOON WILL SHIFT W ON SUN REACHING A PSN FROM NE TX TO FL BAY WITH A SURFACE HIGH DEVELOPING INTERMITTENTLY ALONG THE RIDGE AXIS. LITTLE CHANGE THEN EXPECTED THROUGH MON...THEN THE RIDGE WILL RE-ORIENTATE AGAIN SE TO NW FROM FL BAY TO NE TX MON NIGHT WITH LITTLE CHANGE EXPECTED THROUGH WED....THEN THE RIDGE WILL SHIFT N REACHING PSN FROM TAMPA BAY TO THE MS DELTA ON THU. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL WHICH WAS A GFS/ECMWF BLEND. TAFB NWPS USED FOR SEAS HEIGHTS AND PRIMARY WAVE PERIOD WITH MANUAL ADJUSTMENTS TO MATCH OBSERVATIONS. MEDIUM-HIGH CONFIDENCE. ATLC RIDGE N OF THE AREA COMBINED WITH LOW PRESSURE OVER NW COLOMBIA WILL CONTINUE TO SUPPORT FRESH-STRONG TRADES PRIMARILY OVER THE S CENTRAL CARIBBEAN...EXCEPT INCREASING TO NEAR GALE WITHIN 60 NM OF THE COAST TONIGHT. THE ATLC RIDGE WILL SHIFT SW WITH THE ASSOCIATED GRADIENT RELAXING SOME...AND EFFECTIVELY SHRINKING THE AREA OF AFFECTED STRONG TRADES FROM SUN THROUGH WED...WITH GUIDANCE SUGGESTING THAT THE GRADIENT WILL TIGHTEN AGAIN ON THU WITH FRESH-STRONG E WINDS ACROSS THE CARIBBEAN BETWEEN 70-80W...AND ACROSS THE GULF OF HONDURAS AS WELL. A TROPICAL WAVE OVER THE E CARIBBEAN THIS AFTERNOON WILL CONTINUE W THROUGH THE CENTRAL CARIBBEAN TONIGHT AND MON AND THROUGH THE SW CARIBBEAN ON TUE-WED. A SECOND TROPICAL WAVE WILL PASS 55W ON SUN...ENTER THE E CARIBBEAN ON MON...AND CROSS THE CENTRAL CARIBBEAN ON TUE AND WED. MODERATE TO FRESH TRADES WITH 4-7 FT SEAS WILL PERSIST OVER THE TROPICAL N ATLC WATERS W OF 55W THROUGH THE PERIOD. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL WHICH WAS A GFS/ECMWF BLEND. TAFB NWPS USED FOR SEAS HEIGHTS AND PRIMARY WAVE PERIOD WITH MANUAL ADJUSTMENTS TO MATCH OBSERVATIONS MEDIUM-HIGH CONFIDENCE. THE ATLC RIDGE WILL BECOME ORIENTATED W TO E ALONG 28N BY EARLY TONIGHT...THEN GRADUALLY SHIFT TO A PSN FROM 28N55W TO 24N81W ON TUE AND WED...THEN SHIFT SLIGHTLY N ACROSS THE NW BAHAMAS ON THU. SW FLOW N OF 30N WILL INCREASE TO 10-15 KT ON SUN...AND INCREASE TO 15-20 KT N OF 30N W OF 75W LATE TUE....THEN FURTHER INCREASE TO 20-25 KT BRIEFLY ON TUE NIGHT AND WED NIGHT AS LOW LEVEL TROUGHS ARRIVE ALONG THE COAST OF THE SE CONUS. MODERATE E-SE TRADES ARE OBSERVED S OF THE RIDGE...EXCEPT INCREASING TO FRESH ALONG THE N COAST OF HISPANIOLA AND THE APPROACHES TO THE WINDWARD PASSAGE EACH EVENING...WITH GUIDANCE SUGGESTING AN INCREASE TO 20-25 KT BRIEFLY ON SUN...TUE AND WED EVENINGS. AN UPPER TROUGH EXTENDS FROM NW HISPANIOLA TO THE FL STRAITS WITH UPPER DIFFLUENCE WITHIN 480 NM NE OF THE TROUGH AXIS SUPPORTING ISOL TS/RW WHICH WILL BE CARRIED IN THE WEATHER GRIDS FOR THE FIRST 48 HOURS AS THE TROUGH IS FORECAST TO MOVE NE BACK ACROSS THE BAHAMAS. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 NELSON. NATIONAL HURRICANE CENTER.