000 AGXX40 KNHC 071918 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 318 PM EDT FRI SEP 07 2012 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 MAIN FEATURE OVER THE AREA CONTINUES TO BE A WEAK LOW PRES SYSTEM LOCATED IN THE CENTRAL GULF NEAR 28N89W AS 1012 MB AT 18 UTC WITH A TROUGH SW TO NEAR 26N94W. THE LOW IS DRIFTING SSW. LATEST AND RECENT SATELLITE IMAGERY SHOWED THE ASSOCIATED WEATHER WITH THE LOW AS SCATTERED TSTMS OFFSET TO THE S OF THE LOW DUE TO STRONG NE UPPER LEVEL WINDS. THE TSTMS ARE CONFINED FROM 22N TO 26N BETWEEN 87W AND 92W. WIND OBSERVATIONS NEAR THE LOW ARE REVEALING A SMALL POCKET OF SE-SW WINDS OF 20 KT WITHIN ABOUT 90 NM OF THE LOW IN THE E SEMICIRCLE...HOWEVER SEAS REMAIN LOW IN THE 3-5 FT RANGE. SEAS MAY BE BRIEFLY HIGHER IN AND NEAR THE SCATTERED TSTMS. THE LOW IS RATHER ELONGATED AND DISORGANIZED UNDER THE NLY SHEAR ENVIRONMENT. THE LATEST GLOBAL MODELS ARE IN PRETTY GOOD AGREEMENT THAT THE LOW WILL BEGIN TO MOVE SLOWLY E TONIGHT AND THEN MOVE SLOWLY NE LATE TONIGHT THROUGH SAT NIGHT IN RESPONSE TO A RATHER IMPRESSIVE COLD FRONT FOR THIS TIME OF YEAR FORECAST TO MOVE OFF THE TEXAS COAST ON SAT AFTERNOON. IT APPEARS THAT THE LOW WILL BE ABSORBED BY THE FRONT NEAR OR OVER THE FAR WESTERN PART OF THE FLORIDA PANHANDLE. GLOBAL MODELS AND EVEN THE MEAN GFS AND ECMWF ENSEMBLES AGREE ON THIS SCENARIO. WINDS MAY BRIEFLY INCREASE TO 20-25 KT WITHIN 180 NM OF THE LOW IN THE SE SEMICIRCLE OF THE LOW IN ABOUT 24 HRS NEAR 29N88W ...BUT IT IS UNLIKELY THAT THESE WINDS WILL CONTINUE AT THOSE SPEEDS SAT AS THE LOW BEGINS TO TRACK NE AHEAD OF THE COLD FRONT. ONCE THE FRONT MOVES OFF THE TEXAS COAST SAT...IT WILL QUICKLY REACH A POSITION FROM THE WESTERN FLORIDA PANHANDLE SW TO FAR SRN TEXAS/NE MEXICO BY EARLY SAT EVENING...FROM NE FLORIDA SW TO NE TEXAS BY EARLY SUN...FROM CENTRAL FLORIDA TO 24N98W EARLY MON...THEN BECOME STATIONARY WHILE WEAKENING FROM S CENTRAL FLORIDA TO FAR WESTERN BAY OF CAMPECHE TUE AND DISSIPATE BY EARLY WED AS STRONG HIGH PRES BUILDS E ACROSS THE GULF IN ITS WAKE. THE RESULTANT PRES GRADIENT SHOULD ALLOW FOR A BRIEF EPISODE OF N-NE 15-20 KT WINDS OVER MAINLY THE COASTAL WATERS OF THE NW GULF LATE SAT NIGHT AND SUN BEFORE DIMINISHING TO 10-15 KT LATER LATER IN THE DAY SUN WHILE VEERING TO THE NE EARLY ON MON AND TO THE E DURING MON AFTERNOON THROUGH WED. SEAS BEHIND THE FRONT SHOULD BUILD TO NO HIGHER THAN 5-6 FT SUN BEFORE SUBSIDING TO 2-3 FT MON AND TUE. THE RIDGE TO THE N WILL CONTINUE TO SLIDE EASTWARD TUE AND WED. SOUTHWEST NORTH ATLC S OF 31N W OF 55W... THE PRELIMINARY 18 UTC SURFACE ANALYSIS HAS A WEAK 1016 MB HIGH OVER THE BAHAMAS NEAR 25N78W WITH A RIDGE W INTO THE FAR ERN GULF OF MEXICO. TROPICAL STORM LESLIE IS E OF OF THE BASIN NEAR 27.1N 62.2W OR ABOUT 390 MILES SSE OF BERMUDA AT 2 PM MOVING SLOWLY N A WEAK STEERING ENVIRONMENT WITH MAXIMUM WINDS OF 60 KT WITH GUSTS TO 70 KT AND A MINIMAL CENTRAL PRES OF 982 MB. BASED ON THE LATEST 15 UTC NHC ADVISORY...LESLIE IS FORECAST TO CONTINUE TO MOVE SLOWLY N OVER THE NEXT FEW DAYS WHILE GRADUALLY STRENGTHENING ...REACHING NEAR 27.1N 62.2W EARLY THIS EVENING...NEAR 28.0N 62.2W EARLY SAT MORNING...NEAR 29.0N 62.2W BY EARLY SAT EVENING THEN MOVE N OF THE AREA DURING SUN. PLEASE REFER TO NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC. THE SLOW MOVING CYCLONE WILL CONTINUE TO GENERATE LARGE LONG PERIOD SWELL IN ALL DIRECTIONS AFFECTING A GOOD PORTION OF THE ZONES...INCLUDING WATERS NEAR AND AROUND BERMUDA AND THE U.S. EAST COAST FROM CENTRAL FLORIDA NORTHWARD INTO EARLY NEXT WEEK. THESE SWELLS WILL CARRY WITH THEM THE POTENTIAL FOR POTENTIALLY LIFE-THREATENING SURF CONDITIONS AND RIP CURRENTS. LATEST BUOY OBSERVATIONS ARE AS FOLLOW...BUOY 41049 AT 27.5N 63W EARLY HAD SEAS IN THE MID TO UPPER 20 FT RANGE...BUT PRESENTLY DOWN TO 10-19 FT...BUOY 41049 AT 32N69W W OF BERMUDA HAS MAX SEAS OF 11 FT...BUOYS 41043 AT 21N65W HAS COMBINED SEAS OF 8 FT IN A N SWELL AND BUOY 41047 AT 28N72W HAS COMBINED SEAS OF 10 FT IN A NE TO E SWELL. THE GENERATED SWELLS HAVE A NLY COMPONENT S OF 26N...AND A NE TO E SWELL COMPONENT N OF 26N. LIGHT WINDS WILL BE FOUND OVER THE WESTERN PART OF THE AREA THROUGH LATE SAT NIGHT WHERE THE WEAK 1016 MB HIGH WILL CHANGE LITTLE. SEAS ARE 2-3 FT SW OF THE BAHAMAS AND SEAS IN THE RANGE OF 7-10 FT IN A NE SWELL TO THE NE OF THE BAHAMAS OUTSIDE THE 12 FT AND GREATER SEA HEIGHTS ASSOCIATED WITH LESLIE CONFINED TO THE NE AND E PORTIONS OF THE BASIN. THESE SEAS WILL LAST INTO EARLY SUN BEFORE THEY BEGIN TO SUBSIDE THROUGH WED. MODELS BRING THE GULF OF MEXICO COLD FRONT INTO THE FAR NW WATERS EARLY SUN...AND QUICKLY REACH FROM NEAR 31N72W TO CENTRAL FLORIDA EARLY MON AND FROM 29N65W TO 26N73W TO S CENTRAL FLORIDA BY EARLY TUE...AND FR0M NEAR 26N65W TO THE CENTRAL BAHAMAS AND DISSIPATING TO S FLORIDA BY WED WITH STRONG HIGH PRES BUILDING EASTWARD ACROSS THE BASIN BEHIND IT. THE INDUCED PRES GRADIENT WILL PRODUCE NE WINDS OF 15-20 KT BEHIND THE FRONT WITH SEAS BUILDING TO 6-9 FT BEHIND IT. WINDS AHEAD OF THE FRONT...PER GFS 10M WIND GUIDANCE...ARE EXPECTED TO BE SW-W AROUND 10-15 KT WITH LIGHTER WINDS FROM THE SE-S AT 5-10 KT S OF ABOUT 23N. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... RESIDUAL LONG PERIOD MAINLY N SWELLS FROM LESLIE AFFECTING THE ATLC EXPOSURES OF THE NE CARIBBEAN AND WATERS NEAR HISPANIOLA ARE FORECAST TO LAST INTO EARLY SUN WHILE SLOWLY SUBSIDING. THESE SWELLS WILL RESULT IN SEAS OF AROUND 6-8 FT...THEN SUBSIDE TO 5-7 FT LATER ON SUN AND 3-5 FT MON THROUGH WED. LIGHT TO MODERATE E WINDS WILL PERSIST ELSEWHERE OVER MOST OF THE REGION...EXCEPT UP TO 20 KT IN THE S CENTRAL CARIBBEAN...AND OCCASIONALLY 15-20 KT IN THE GULF OF HONDURAS MAINLY AT NIGHT. WAVE HEIGHTS WILL REMAIN 6 FT OR LESS. NOTE...GRIDDED MARINE FORECAST IS AVAILABLE AT WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE GULF OF MEXICO... .NONE. CARIBBEAN SEA AND TROPICAL N ATLC... .NONE. SW N ATLANTIC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ FORECASTER AGUIRRE