000 AGXX40 KNHC 271857 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 255 PM EDT TUE SEP 27 2011 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLC...AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... THE 18 UTC PRELIMINARY SURFACE ANALYSIS SHOWS A TROUGH EXTENDING FROM THE FLORIDA BIG BEND AREA SSE TO THE FAR SE GULF WATERS. SHOWER AND TSTMS ARE EXPECTED TO DEVELOP MAINLY OVER THE FAR SE WATERS THIS AFTERNOON WITH POSSIBLE GUSTY WINDS AND ROUGH SEAS WITH THE ACTIVITY. THE ACTIVITY SHOULD BE LESS WIDESPREAD THAN THE PAST COUPLE OF DAYS AS DRIER ALOFT MOVES INTO THE AREA NOW THAT THE UPPER TROUGH IS PULLING FURTHER AWAY FROM THE GULF. LATEST NE GULF BUOY REPORTS SHOW W WINDS OF 5-10 KT W OF THE TROUGH TO NEAR 88W...WHILE VARIABLE MAINLY SE-S WINDS OF 5-10 KT ARE EVIDENT TO THE SE OF THE TROUGH. THE TROUGH WILL DISSIPATE THROUGH TONIGHT. A 1016 MB HIGH CENTERED IN THE N CENTRAL PORTION NEAR 27N90W MAINTAINS A WEAK PRES PATTERN ELSEWHERE ACROSS THE GULF. BUOYS ARE REPORTING SEAS IN THE RANGE OF 1-2 FT ACROSS THE AREA... EXCEPT FOR IN THE SW GULF WHERE BUOY 42055 AT 22N94W IS INDICATING SEAS OF 3-4 FT. SIMILAR SEAS ARE SEEN IN THE FAR WESTERN PORTION OF THE NW ZONE ALONG THE COAST OF TEXAS. THESE SEAS EARLIER BUILD IN A MODERATE SLY FLOW. THE FLOW HAS SINCE DIMINISHED...AND SO THESE SEAS WILL SUBSIDE TO 2-3 FT TONIGHT. THE HIGH CENTER IN THE N CENTRAL GULF WILL CONTINUE THROUGH WED NIGHT...THEN THEN RE-LOCATE TO THE NW GULF THU AND FRI. A COLD FRONT WILL MOVE INTO THE NW GULF FRI...AND REACH FROM NEAR TAMPA FLORIDA TO NE MEXICO BY SAT AND DISSIPATE FROM S CENTRAL FLORIDA TO THE SOUTHERN PORTION OF THE MIDDLE GULF SUN AS THE FIRST SIGNIFICANT HIGH PRES AREA OF THE FALL SEASON BUILDS ACROSS THE ENTIRE GULF AS MODELS SUGGEST. THE RESULTING TIGHTENING PRES GRADIENT WILL BRING NE WINDS OF 15-20 KT ACROSS THE AREA...WITH THE HIGHER RANGE OF THE WINDS CONFINED TO MAINLY THE NORTHERN HALF PORTION. EXPECT SEAS TO BUILD TO THE RANGE OF ABOUT 4-6 FT N OF ABOUT 26N LATE FRI INTO SAT AS LOWER SEAS OF 2-4 FT SHOULD BE CONFINED TO S OF 26N. SW N ATLC S OF 31N W OF 65W... THE 18 UTC PRELIMINARY SURFACE ANALYSIS SHOWS A NEARLY STATIONARY 1020 HIGH LOCATED JUST SW OF BERMUDA WITH A RIDGE SW TO THE NW BAHAMAS. A WEAK TROUGH EXTENDS FROM NEAR 31N78W SW TO CENTRAL FLORIDA. VISIBLE SATELLITE IMAGERY FROM EARLY THIS AFTERNOON SHOW SCATTERED SHOWERS AND TSTMS E AND SE OF THE TROUGH TO THE CENTRAL BAHAMAS. BUOY OBSERVATIONS FROM ACROSS THE AREA SHOW NE-E 15 KT WINDS S AND SE OF THE RIDGE...EXCEPT NE-E 15-20 KT WINDS IN THE FAR SE PORTION AND SE TO S WINDS 10-15 KT W OF THE RIDGE. BUOY REPORTS ALONG WITH A FEW OBSERVATIONS AND EVEN ALTIMETER DATA FROM TODAY SHOW SEAS IN THE 3-5 FT RANGE E OF THE BAHAMAS...EXCEPT S OF 25N WHERE SLIGHTER HIGHER SEAS OF 5-6 FT ARE NOTED DUE TO A LINGERING N SWELL. SEAS N OF 27N W OF 78W ARE 3-5 FT IN A N SWELL...BUT WILL BUILD TO 4-6 FT TONIGHT AS A BATCH OF SE SWELLS ARRIVES AND MIXES IN WITH THE NLY SWELL. SEAS W OF THE BAHAMAS ARE 2-3 FT. THE REMNANT LOW OF WHAT WAS RECENTLY TROPICAL DEPRESSION OPHELIA IS CURRENTLY SE OF THE AREA IN THE NW TROPICAL N ATLC NEAR 18N60W WITH A PRES OF 1010 MB MOVING SLOWLY NW. IT IS FORECAST TO BE IN THE VICINITY OF THE FAR SE BOUNDARY OF THE AREA THU THROUGH FRI...THEN TURN MORE TO THE N AND PASS TO JUST E OF THE ZONE VERY NEAR 28N65W THEN TURN NE AND ACCELERATE NORTHEASTWARD LATE SAT AND SUN. THE LOW HAS A HIGH CHANCE OF INTENSIFYING INTO A TROPICAL CYCLONE THROUGH THIS PERIOD. THE RIDGE IS FORECAST TO WEAKEN AND SHIFT NORTHEASTWARD THROUGH SUN AS THE FORMER REMNANT LOW OF OPHELIA IN THE NW TROPICAL N ATLC MORE TO THE N AND EVENTUALLY TO THE NE. AS THIS HAPPENS...A WEAK FRONT WILL PUSH INTO THE FAR NW WATERS FRI...AND MOVE TO NEAR A LINE FROM NEAR 31N74W TO THE CENTRAL BAHAMAS BY SAT AFTERNOON. MODELS SUGGEST THAT THE FRONT WILL REMAIN ON THE WEAK BY THEN...OR EVEN PERHAPS BE MORE OF A TROUGH. WINDS ON EITHER SIDE OF THE FRONT ARE EXPECTED TO BE ON THE LIGHT SIDE BUT WITH A WINDS SHIFT FROM SLY TO NW-N ACROSS THE BOUNDARY. A STRONGER COLD FRONT IS FORECAST TO MOVE INTO THE NW WATERS SAT AND QUICKLY REACH FROM 31N66W TO THE SE BAHAMAS BY SUN AS IT WEAKENS. THE STRONG GULF OF MEXICO HIGH PRES WILL THEN BUILD EASTWARD INTO THE NW PORTION BEHIND TIGHTENING THE PRES GRADIENT WITH WINDS BECOMING N-NE 15-20 KT AND SEAS BUILDING TO 6 TO 9 FT IN THAT PORTION OF THE ZONE SUN. THE UNCERTAINTY WITH THIS FORECAST LIES PRIMARILY WITH THE REMNANT LOW OF OPHELIA. IF THE LOW DOES INTENSIFY INTO A TROPICAL CYCLONE...IT WILL HAVE SIGNIFICANT IMPACT ON WINDS SEAS OVER THE FAR EASTERN PORTION OF THE THU THROUGH SAT. OF COURSE THE IMPACTS WILL BE SIGNIFICANT IF THE LOW MOVES FURTHER WEST INTO THE ZONE OR ALONG 65W DURING THU THROUGH SAT. STAY TUNED TO THE LATEST TROPICAL WEATHER OUTLOOKS AND LATEST MARINE FORECASTS FOR UPDATES ON THE LOW AND ITS FUTURE TRACK AND INTENSITY. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... THE REMNANT LOW OF TROPICAL STORM OPHELIA IS ANALYZED NEAR 18N60W 1010 MB AT 1800 UTC THIS AFTERNOON MOVING SLOWLY NW. AN ASCAT PASS FROM THIS AFTERNOON SHOWED A VERY SHARP CYCLONIC TURNING OF THE WINDS WITH THE LOW...WITH 20-30 KT WINDS WITHIN 180 NM THE SE QUADRANT...180 IN THE N SEMICIRCLE AND 60 NM IN THE SW QUADRANT. NE TO E 20 KT WINDS ARE ELSEWHERE FROM 18N-24N BETWEEN 55W AND 65W NE-E 20 KT WINDS ARE NOTED. SEAS OF 7-10 FT ARE POSSIBLE IN THE NE AND SE QUADRANTS OF THE LOW...AND SEAS OF 6-8 FT ELSEWHERE N OF 18N. NUMEROUS SQUALLS AND TSTMS ARE LOCATED FROM 14N TO 19N BETWEEN 56W AND 61W. THE REMNANT LOW IS FORECAST TO REACH NEAR 19N60W BY EARLY WED...NEAR 21N62W EARLY THU AND TO WED...AND TO JUST NW OF THE TROPICAL N ATLC ZONE LATE THU NIGHT INTO SAT.GLOBAL MODELS...AND EVEN THE REGIONAL NAM HAVE BEEN VERY PERSISTENT IN STRENGTHENING THE LOW AGAIN INTO A TROPICAL CYCLONE OVER THE NEXT 24-48 HOURS ...OR EVEN MUCH SOONER. WILL AWAIT UPDATED SURFACE AND UPPER LEVEL DATA TO SEE IF MAJOR CHANGES ARE REQUIRED WITH RESPECT TO WINDS AND SEAS WITH THE LOW THROUGH THE REST OF THE WEEK. CHANGES WITH RESPECT TO ASSOCIATED SEAS WITH THE LOW WILL DEPEND ON JUST HOW STRONG THE LOW BECOMES...AND IT DOES REGENERATE BACK TO A TROPICAL STORM. FOR NOW WILL LEAN TOWARDS LOWER VALUES THAN THE NOAA WAVEWATCH GUIDANCE FOR THIS FORECAST. BUOYS 41043 AT 21N65W AND 41044 AT 22N59W ARE NOW SHOWING LOWER SEA HEIGHTS THAN DURING THE PAST FEW DAYS AS THE LINGERING N SWELL SUBSIDES. OBSERVATIONS FROM BUOYS 41101 AT 15N56W AND BUOY 41040 AT 14N53W SHOW MUCH LOWERS SEAS OF 2-3 FT UNDER A LIGHTER SE WIND FLOW EVIDENT TO THE E AND SE OF THE REMNANT LOW. WARNINGS... GULF OF MEXICO... .NONE. CARIBBEAN SEA AND TROPICAL N ATLC... .NONE. SW N ATLC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER AGUIRRE