000 AGXX40 KNHC 120756 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 356 AM EDT WED SEP 12 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... FRONTAL BOUNDARY BREAKING UP ACROSS THE BASIN THIS MORNING AS W END HAS LIFTED NW TO ALONG THE TEXAS COAST...WHILE E PORTION IS BECOMING STRETCHED NW TO SE FROM THE FLORIDA KEYS TO NEAR 27.5N90W. AS FORECAST BY MODELS...15-20 KT OF ENE FLOW HAS BUILT IN ACROSS THE NE GULF BEHIND BOUNDARY WITH BUOYS SHOWING 4-5 FT ATTM...AND WILL LIKELY PEAK NEAR 4-6 FT OVERNIGHT. LOW-MID LVL DISTURBANCE ACROSS SW GULF MOVING INLAND ATTM AND ASSOCIATED WEATHER EXPECTED TO END OVER WATER THIS MORNING. UPPER LOW OVER LA-ARK FORECAST TO SHIFT SLOWLY E NEXT FEW DAYS AND SHOULD PROVIDE SOME LIFT ACROSS SE QUAD AND ALONG NRN GULF COASTAL WATERS AS IT INTERACTS WITH REMNANT MOISTURE OF FRONTAL BOUNDARY TODAY THROUGH THU MORNING. FRESH ENE FLOW EXPECTED TO CONTINUE ACROSS THE NE GULF THROUGH THU TO MAINTAIN SEAS 4-6 FT THERE...WITH NOCTURNAL PULSES TO AROUND 20 KT. OTHERWISE...WEAK HIGH PRES AND MODERATE ELY FLOW EXPECTED BEYOND THU NIGHT AS BLOCKING PATTERN PREVAILS S OF 30N. SOUTHWEST NORTH ATLC S OF 31N W OF 55W... COLD FRONT BECOMING NEARLY STATIONARY FROM NEAR 31N60W TO 26N67W THEN W AND SOMEWHAT ILL DEFINED TO EXTREME S FLORIDA. FRONTAL ZONE IS LIKELY BETTER DESCRIPTION FOR THIS FEATURE WITH DEEP CONVECTION FIRING N AND NW OF WHERE WE ARE ANALYZING BOUNDARY. TUTT AXIS FROM CENTRAL ATLC TO NE CARIB WILL MEANDER W THROUGH THU NIGHT AND BE NUDGED BACK E BY LARGE UPPER LOW ACROSS NW ATLC THROUGH THE WEEKEND...AND THIS HAS REPERCUSSIONS ON LOCATION OF DISSIPATING FRONTAL ZONE...AND TRAJECTORY OF T.S. NADINE. GLOBAL MODELS CONTINUE TO SHOW VARIOUS VERSIONS OF LOW PRES FORMING ALONG THE FRONTAL ZONE...ORIGINATING SE OF BERMUDA. SOME CYCLONIC TURNING IS ALREADY EVIDENT IN STLT IMAGERY THERE ATTM BUT STILL UNCLEAR THE EVOLUTION OF A LOW. OTHERWISE...HIGH PRES ACROSS ERN U.S. BEHIND FRONT WILL MAINTAIN MODEST PRES GRADIENT AND FRESH NE TO ENE WINDS BEHIND FRONT THROUGH THU BEFORE GRADIENT WEAKENS. MAX WINDS AROUND 20 KT GUSTS TO 25 EXPECTED ACROSS LARGE PORTION OF THE WATERS NW OF FRONT LATE THIS AFTERNOON AND TONIGHT BUILDING SEAS 6-7 FT WITH ISOLATED AREAS TO 8 FT...WITH MAX EXPECTED AROUND 28.5N76W. ELY SWELL FROM NADINE TO MOVE INTO SE PORTIONS FRI MORNING AND WILL PROPAGATE WWD TO THE BAHAMAS SAT MORNING AND INTO E COAST OF FLORIDA LATE SAT. HOWEVER TRAJECTORY OF NADINE AND SHAPE OF WIND FIELD PLACING STRONGEST WINDS AND BROADEST FETCH ACROSS ERN SEMICIRCLE AND BEST SWELL ENERGY TO BE DIRECTED TOWARD NE COAST OF U.S. AND CANADA. SWELL WILL RAISE SEAS TO 6-9 FT ACROSS E AND NE PORTIONS FRI AND SAT AS NADINE LIFTS N. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... HIGH PRES N OF THE AREA WILL MAINTAIN MODERATE TO FRESH TRADE WINDS ACROSS THE S CENTRAL CARIBBEAN WATERS...AND LIGHT TO MODERATE TRADE WINDS ELSEWHERE THROUGH THU BEFORE PRES GRADIENT WEAKENS TO THE W AND SW OF NWD MOVING NADINE. THE TRAJECTORY OF NADINE WILL KEEP ITS CENTER E OF 55W...BUT WILL ELY SWELL...AS MENTIONED ABOVE MOVING INTO THE OFFSHORE WATERS OF THE LEEWARDS AND TROPICAL N ATLC THU AFTERNOON THROUGH FRI. SEAS N OF 18N EXPECTED TO BUILD 8-12 FT THU NIGHT. GLOBAL MODELS IN DISAGREEMENT ON MOTION OF NADINE AFTER DAY 3 AS IT INTERACTS WITH UPPER TROUGH ACROSS NW ATLC...AND WILL IMPACT REGIONAL WIND AND SEAS. VERY LONG PERIOD NE SWELL FROM MICHAEL EXPECTED TO MOVE INTO THE REGIONAL WATERS THIS AFTERNOON AND TONIGHT BUT REMAIN LESS THAN 3 FT. 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