000 AGXX40 KNHC 080804 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 404 AM EDT SAT SEP 08 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 CURRENT MAIN FEATURE OVER THE BASIN CONTINUES TO BE A WEAK 1008 MB LOW PRES SYSTEM LOCATED IN THE N CENTRAL GULF NEAR 28.5N88.5W WITH A CONVERGENT TROUGH SW TO NEAR 27N90.5W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE PRESENTLY FIRING IN A 0 NM WIDE BAND ALONG AND SE OF THE TROUGH. THE LOW IS CURRENTLY STATIONARY...BUT WILL BEGIN TO SHIFT E SHORTLY AND MOVE INTO THE FLORIDA BIG BAND REGION TONIGHT...AHEAD OF APPROACHING COLD FRONT MOVING INTO THE N GULF REGION THIS MORNING. GLOBAL MODELS SUGGESTING SWLY FLOW NEAR 20 KT TO OCCUR TO THE SE OF THE LOW...ALONG AND SE OF THE TROUGH...AS IT SHIFT E ACROSS THE NE GULF TODAY INTO THIS EVENING...WHERE SEAS WILL BUILD 5-7 FT. MODELS ALSO SUGGESTING THIS FEATURE TO BECOME ELONGATED AND LEAVE NARROW TROUGHING OUT AHEAD OF THE COLD FRONT BY SOME 60 NM. COLD FRONT TO SINK INTO NRN GULF AFTER 00Z THIS EVENING WITH NNE FLOW 20 KT IMMEDIATELY BEHIND IT TO THE W OF 90W AND NLY 15-20 KT E OF 90W 06-12Z. LITTLE TIME FOR WAVE GROWTH IN THIS SCENARIO AND COASTAL SEAS EXPECTED TO BUILD QUICKLY TO 3-4.5 FT BEHIND THE SINKING BOUNDARY. LLVL VORTICITY AND ENERGY ASSOCIATED WITH LOW WILL SHIFT NE ACROSS N FLORIDA SUN-SUN NIGHT AS FRONT SINKS FARTHER S AND WEAKENS ALONG 25-25N. HIGH PRES BUILDING BEHIND FRONT WILL LIKELY ENHANCE NELY FLOW ALONG WRN TAIL OF FRONT OFF THE S TEXAS COASTAL WATERS TO NEAR 20 KT SUN AFTERNOON AND EVENING. BOUNDARY THEN EXPECTED TO WASH OUT THROUGH TUE AND BECOME NEARLY W TO E ALONG 26N WITH COASTAL TROUGHING ALONG LOWER MEXICAN COAST AIDING IN DEVELOPING POSSIBLE WAVE ALONG TAIL OF BOUNDARY IS WRN GULF. HIGH PRES BUILDING ACROSS SE U.S. BEHIND FRONT THE ENHANCE GRADIENT BEHIND DYING FRONT ACROSS FLORIDA AND E GULF AND INCREASE ELY WINDS ACROSS NE GULF TO 15-20 KT LATE TUE AFTERNOON AND NIGHT AND TO 20 KT WED...WITH SEAS BUILDING TO 4-7 FT WED. SOUTHWEST NORTH ATLC S OF 31N W OF 55W... WEAK 1015 MB HIGH CURRENTLY NE OF THE BAHAMAS BETWEEN LESLIE AND FLORIDA PENINSULA YIELDING LIGHT TO MODERATE S TO SW FLOW W OF 75W...AND VARIABLE 10 KT OR LESS E TO 70W. LESLIE LIFT OUT TO N VERY SLOWLY...AND ATTEMPTING TO WRAP CONVECTIVE BANDS ALL THE WAY AROUND CENTER...AND WILL LIKELY INTENSIFY TO HURRICANE WITHIN 24 HOURS. TUTT LOW AND ASSOCIATED TUTT AXIS EXTENDING SW HAS BECOME GRADUALLY ELONGATED PAST FEW DAYS AND LESS ENERGETIC...WITH CONDITIONS W OF 75W HAVING STABILIZED SOMEWHAT PAST 36 HOURS. AS LESLIE LIFTS OUT TO THE N NEXT 36-48 HOURS...AND COLD FRONT MOVES INTO NW PORTIONS SUN AFTERNOON AND EVENING...SWLY FLOW TO INCREASE ACROSS NW CORNER TO 20-25 KT AHEAD OF GULF LOW AND TROUGH...AND THEN N TO NE NEAR 20 KT BEHIND FRONT MON AFTERNOON AND NIGHT. LONG PERIOD SWELL GENERATED FROM LESLIE WILL CONTINUE TO PROPAGATE AWAY FROM THE SYSTEM AND THROUGH ALL LOCAL WATERS...AND HIT COASTS... REEFS...AND SHOALS OF LOCAL SHORELINES WITH STRONG AND PERSISTENT SURF. MODERATE TO HIGH SURF AND VERY STRONG RIP CURRENTS WILL PERSIST IN THESE SURF ZONES FOR THE NEXT FEW DAYS BEFORE ABATING...AND WILL BE PERSISTENT REGARDLESS OF TIDES. BUOYS TO THE NW OF LESLIE REMAIN IN THE 10-11 FT RANGE...AND STRONGEST SWELL IS MOVING NW TOWARD THE CAROLINAS AND MID ATLC STATES. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... LONG PERIOD NLY SWELL FROM LESLIE AFFECTING THE ATLC PASSAGES OF THE NE CARIBBEAN FORECAST TO LAST INTO EARLY SUN BEFORE SLOWLY SUBSIDING. THESE SWELLS WILL RESULT IN SEAS OF AROUND 5-8 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... BUILDING TO 7 FT ALONG AND OFFSHORE OF COLOMBIA THIS EVENING THROUGH SUN...WHERE SEAS ARE EXPECTED TO CONTINUE 6-8 FT THROUGH TUE NIGHT. 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 STRIPLING