000 AGXX40 KNHC 060604 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 204 AM EDT SUN SEP 6 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 INTO 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. A MID-UPPER LEVEL TROUGH CONTINUES TO DIG S ACROSS THE CENTRAL AND EASTERN GULF AND ENHANCES CONVECTION DURING AFTERNOON INTO EARLY EVENING...AND EXPECT THE SAME CONVECTIVE ENHANCEMENT AGAIN THIS AFTERNOON...THUS WILL BE DENOTED IN WEATHER GRIDS. A 1015 MB SURFACE HIGH ANALYZED OVER THE NE GULF HAS A RIDGE EXTENDING NW TO THE SW LA COAST AND A RIDGE EXTENDING SE TO THE NW COAST OF CUBA. A TROUGH EXTENDS SW ACROSS THE FL STRAITS TO NEAR 23N83W. THE TROUGH WILL SHIFT N ACROSS THE FAR SE GULF WATERS TODAY AND LOSE IDENTITY TONIGHT. THE HIGH CENTER WILL SHIFT E TO OVER EXTREME SW FL ON TUE...THEN SHIFT N ALONG THE GULF COAST OF SW FL TO NEAR TAMPA BAY ON WED...THEN SHIFT WNW TO OVER THE NE GULF WHERE IT WILL MEANDER THU AND FRI. EXPECT LIGHT AND VARIABLE WINDS ACROSS THE GULF N OF 23N THROUGH TUE...THEN THE SE RETURN FLOW WILL INCREASE TO 10-15 KT ACROSS THE W-CENTRAL GULF EACH NIGHT THROUGH THE END OF THE PERIOD. AN INVERTED THERMAL TROUGH WILL DEVELOP EACH AFTERNOON OVER THE YUCATAN PENINSULA...AND THEN MOVE W-NW ACROSS THE SW GULF WATERS...GENERALLY TO THE S OF 22N BETWEEN 90-93W DURING THE EVENING THROUGH LATE NIGHT HOURS...REACHING ALONG 94-95W DURING THE EARLY DAYLIGHT HOURS...AND THEN DISSIPATING BY EARLY AFTERNOON. EXPECT THIS TROUGH TO BE ACCOMPANIED BY A NE-E 10-15 KT NOCTURNAL EVENTS THROUGH WED NIGHT...THEN GUIDANCE SUGGESTS A 15-20 KT EVENT ON THU NIGHT. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED INTO 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 N OF THE AREA COMBINED WITH LOW PRESSURE OVER NW COLOMBIA WILL CONTINUE TO ENHANCE FRESH TRADES ACROSS THE THE S- CENTRAL WATERS...EXCEPT INCREASING TO STRONG WITHIN ABOUT 210 NM OF THE COLOMBIAN COAST EACH NIGHT WITH THESE CONDITIONS CONTINUING INTO THE EARLY MORNING HOURS...BUILDING COMBINED SEAS TO 7-10 FT. A TROPICAL WAVE OVER THE CENTRAL CARIBBEAN TODAY WILL PASS THROUGH THE SW CARIBBEAN TONIGHT THROUGH TUE NIGHT...AND THROUGH THE GULF OF HONDURAS ON WED. A SECOND TROPICAL WAVE WILL REACH THE CENTRAL CARIBBEAN LATE TODAY...REACH THE SW CARIBBEAN ON TUE EVENING...AND REACH THE GULF OF HONDURAS AREA ON WED NIGHT. EXPECT A MODERATE-FRESH NE-E-SE WIND SHIFT NEAR THE WAVES. N-NE 20-30 KT WINDS WILL SPREAD W INTO THE TROPICAL WATERS NEAR 16N55W ON THU EVENING IN ASSOCIATION WITH TROPICAL STORM GRACE. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED INTO 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. AN E TO W RIDGE EXTENDS FROM 22N55W TO 24N79W TO THE NW BAHAMAS. A 1013 MB SURFACE LOW IS CENTERED NEAR 32N60W WITH A TROUGH EXTENDING SW ACROSS THE NW BAHAMAS TO THE FL STRAITS AND IS ACCOMPANIED BY ISOL TS. THE WEAK LOW WILL MEANDER OVER THE SUBTROPICAL WATERS N OF THE BAHAMIAN CHAIN TODAY...THEN WEAKEN TO AN OPEN TROUGH BETWEEN 80-82W ON MON THROUGH THU. A SURFACE HIGH WILL DEVELOP NEAR 25N63W ON MON WITH A RIDGE EXTENDING W ACROSS THE NORTHERN BAHAMAS. THE HIGH WILL CONTINUE TO SHIFT N MON NIGHT REACHING NEAR 28N70W LATE TUE WITH THE RIDGE EXTENDING TO NEAR 29N79W. THE HIGH WILL SHIFT W TO NEAR 28N75W LATE WED THEN MEANDER THROUGH THU WITH A RIDGE EXTENDING E AND W ALONG 28N. EXPECT E-SE 10-15 KT FLOW ACROSS THE TROPICAL WATERS S OF THE RIDGE EACH NIGHT....OTHERWISE 5-10 KT FLOW NEAR THE RIDGE AND LOW AND TROUGH. THE EASTERLY TRADES WILL INCREASE TO 15-20 KT ACROSS THE TROPICS WELL E OF THE LEEWARDS...NEAR 20N56W ON THU NIGHT IN ADVANCE TROPICAL CYCLONE GRACE. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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.