000 AGXX40 KNHC 061830 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 230 PM 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. FOR WAVEHEIGHTS USED BLEND OF LATEST MWW3 WITH PREVIOUS INCORPORATED TAFB NWPS. HIGH CONFIDENCE. A RATHER SHARP MID/UPPER LEVEL TROUGH EXTENDS FROM AN UPPER CYCLONIC CIRCULATION OVER S CAROLINA SW TO THE FLORIDA PANHANDLE AND TO 25N88W TO THE NW YUCATAN PENINSULA. SCATTERED SHOWERS AND TSTMS ARE QUICKLY DEVELOPING E AND SE OF THE TROUGH...AND WILL CONTINUE TO INCREASE IN COVERAGE INTO THIS EVENING AGAIN AS IN PREVIOUS DAYS. THIS ACTIVITY IS ACCOMPANIED BY FREQUENT LIGHTNING STRIKES AND GUSTY WINDS PRODUCING ROUGH SEAS. A 1015 MB LOW IS NEAR 28N95W...WHILE A WEAK PRES PATTERN EXISTS ELSEWHERE. LATEST BUOY OBSERVATIONS ARE REPORTING GENERALLY GENTLE WINDS THROUGHOUT FROM THE SE IN DIRECTION...EXCEPT IN CYCLONIC FASHION OVER THE NE GULF AROUND THE 1015 MB LOW. SEAS REMAIN RELATIVELY LOW...IN THE 1-2 FT RANGE. THE 1015 MB LOW NEAR 28N95W WILL MOVE SW TO NEAR 27N91W BY EARLY MON THEN DRIFT NE THROUGH TUE WHILE WEAKENING TO A TROUGH. THE WESTERN PERIPHERY OF ATLC HIGH PRES WILL BUILD BACK TO THE W ACROSS THE AREA BEGINNING TUE AND THROUGH FRI WITH A WEAK HIGH PRES CENTER DEVELOPING OVER THE NE GULF. SEAS WILL REMAIN IN THE 1-2 FT RANGE. 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 AND AGAIN FRI NIGHT. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED INTO PREVIOUS OFFICIAL. FOR WAVEHEIGHTS USED BLEND OF LATEST MWW3 WITH PREVIOUS INCORPORATED TAFB NWPS. HIGH CONFIDENCE...EXCEPT AVERAGE CONFIDENCE TROPICAL N ATLC LATE THU AND FRI. 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 THROUGH WED NIGHT WITH THESE CONDITIONS CONTINUING INTO THE EARLY MORNING HOURS RESULTING IN COMBINED SEAS OF 7-10 FT...BUT SUBSIDING TO 5-6 FT BY FRI. A TROPICAL WAVE OVER THE CENTRAL CARIBBEAN IS NEAR 75W MOVING W AT 15-20 KT. THIS WAVE WILL MOVE ACROSS THE SW CARIBBEAN TONIGHT THROUGH TUE NIGHT...AND THROUGH THE GULF OF HONDURAS ON WED. A SECOND TROPICAL WAVE WILL CONTINUE WESTWARD ACROSS THE CENTRAL CARIBBEAN THROUGH TUE...REACH THE SW CARIBBEAN ON TUE EVENING...AND REACH THE GULF OF HONDURAS AREA ON WED NIGHT. A THIRD TROPICAL WAVE INTRODUCED THIS MORNING ALONG 52W FROM 11N- 16N IS MOVING W ABOUT 15 KT. THIS WAVE WAS CAPTURED NICELY BY VISIBLE IMAGERY. THE 1126 UTC ASCAT PASS FROM THIS MORNING SHOWED A CLEAR NE TO SE WIND SHIFT ACROSS THE WAVE. THIS WAVE WILL ENTER THE FAR EASTERN TROPICAL N ATLC WATERS LATE TONIGHT...MOVE ACROSS THE REST OF THOSE WATERS MON AND MON NIGHT ...THE EASTERN CARIBBEAN TUE THROUGH WED...AND THE CENTRAL CARIBBEAN THU AND FRI. N-NE 20-30 KT WINDS AND SEAS BUILDING TO 8-11 FT WILL SPREAD W INTO THE TROPICAL WATERS NEAR 16N55W ON THU EVENING WITH CONDITIONS POSSIBLY INCREASING TO TROPICAL STORM CONDITIONS ON FRI IN ASSOCIATION WITH TROPICAL STORM GRACE CURRENTLY WELL E OF THE AREA. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED INTO PREVIOUS OFFICIAL. FOR WAVEHEIGHTS USED BLEND OF LATEST MWW3 WITH PREVIOUS INCORPORATED TAFB NWPS. HIGH CONFIDENCE. STILL THE MAIN FEATURE IS RIDGE THAT EXTENDS NEAR 23N/24N E OF THE BAHAMAS AS DEFINED IN THE 1502 ASCAT PASS WINDS AND IN LOW LEVEL MOTION. A WEAK SURFACE TROUGH...REMNANTS OF A WEAK LOW...EXTENDS FROM NEAR 29N65W SW TO 28N70W TO JUST E OF THE CENTRAL BAHAMAS. THE FORECAST FOR THIS PACKAGE WILL HAVE ONLY MINOR CHANGES FROM THE PREVIOUS ONES. THE TROUGH WILL SLOWLY MOVE WESTWARD TOWARDS THE N AND CENTRAL FLORIDA COASTS MON THROUGH THU WHILE WEAKENING. A SURFACE HIGH WILL DEVELOP NEAR 25N63W ON MON WITH A RIDGE EXTENDING W ACROSS THE NORTHERN BAHAMAS. THE HIGH WILL SHIFT N ON MON NIGHT REACHING NEAR 28N70W LATE TUE WITH THE RIDGE EXTENDING WESTWARD TO NEAR 29N79W. THE HIGH WILL THEN SHIFT W TO NEAR 28N75W LATE WED THEN MEANDER THROUGH FRI WITH A RIDGE EXTENDING ALONG 28N. WINDS WILL REMAIN IN THE RATHER GENTLE RANGE WITH SEAS LITTLE CHANGES TO THE CURRENT OBSERVED SEAS OF 1-3 FT. THE EXCEPTION IS BETWEEN THE SE BAHAMAS AND HISPANIOLA WHERE E WINDS WILL PULSE TO 15-20 KT DURING THE NIGHT TIME HOURS BUILDING SEAS THERE TO 4-5 FT. THE ELY TRADES WILL INCREASE TO 15-20 KT ACROSS THE TROPICS WELL E OF THE LEEWARDS...NEAR 20N56W BEGINNING 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 AGUIRRE. NATIONAL HURRICANE CENTER.