000 AGXX40 KNHC 231851 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 250 PM EDT TUE OCT 23 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... 1023 MB HIGH CENTERED ALONG COAST OF CAROLINAS COMBINING WITH OLD FRONTAL ZONE/SHEARLINE STRETCHED ENE-WSW THROUGH CENTRAL BAHAMAS TO NW CUBA AND MAINTAINING FRESH ENE WINDS THROUGH STRAITS AND ACROSS EXTREME SE GULF. OTHERWISE...MODERATE E TO SE FLOW PREVAILS. BUOYS ACROSS SE QUARTER OF GULF SHOWED SEAS TO 8 FT IN PREVAILING ENE FLOW OF PAST 24 HOUR. HIGH WILL SHIFT SLOWLY E NEXT 48 HOURS AS SANDY BEGINS TO SLOWLY LIFT OUT OF CARIB AND TIGHTEN GRADIENT EVEN FURTHER ACROSS SE AND E PORTIONS OF GULF...WHILE SLOWLY BACKING. GFS SEEMS TO BE MODEL OF CHOICE REGARDING SANDY AND THUS WW3 SHOULD YIELD GOOD RESULTS. SEAS TO BUILD TO 6-9 FT ACROSS SE GULF BY THU MORNING AND 9-12 FT THROUGH THE STRAITS...AND POSSIBLY 15-18 FT WITHIN THE FLORIDA CURRENT IN SWELL VS CURRENT SCENARIO. BROADENING OF WIND FIELD OF SANDY AS IT MOVES THROUGH BAHAMAS WILL EXPAND N TO NE WINDS 20-25 KT ACROSS MUCH OF E HALF OF BASIN BY FRI. SW N ATLC S OF 31N W OF 65W... SHEARLINE MENTIONED ABOVE COMBINING WITH HIGH PRES TO THE NNW TO PRODUCE A BROAD ZONE OF 20-25 KT WINDS AND SEAS TO 8 FT NE OF THE N HALF OF BAHAMAS AND THROUGH THE STRAITS OF FLORIDA...WHILE FRESHENING EASTERLIES TO THE S WILL CONTINUE TO INCREASE AS SANDY DEEPENS NEXT 24-36 HOURS. SANDY OF MAIN FOCUS OF FORECAST. HIGH PRES WILL REMAIN N AND NW OF SANDY AS IT EXITS CARIBBEAN NEXT 48 HOURS AND COMBINE WITH MONSOONAL ORIGINS TO PRODUCE VERY LARGE WIND FIELD SHIFTING NNE WITH SANDY. CURRENT NELY FETCH N OF SHEAR LINE ALREADY YIELDING 6-8 FT SEAS NE OF BAHAMAS AND 5-6 FT ALONG THE FLORIDA COASTS. VERY DANGEROUS SCENARIO IS DEVELOPING WITH SANDY AS SUFFICIENTLY SLOW MOVEMENT...PRE EXISTING HIGH SEAS...VERY LARGE WIND FIELD...AND ONSHORE FLOW DURING HIGH LUNAR TIDES COULD SPELL EXTREME COASTAL FLOODING AND EROSION FOR FLORIDA AND CERTAINLY BAHAMAS WED NIGHT THROUGH SAT. WW3 FORECASTING 12 FT SEAS TO REACH CENTRAL FLORIDA COAST BY 18Z THU WITH SEAS BUILDING 20-35 FT WITHIN THE COASTAL WATERS BY 18Z FRI. THIS COULD EVOLVE INTO A HISTORICAL EVENT AND FO'S ARE ENCOURAGED TO ADVERTISE THIS EVENT VERY HARD. NELY SWELL WILL CONTINUE TO IMPACT FLORIDA AND SE COASTS THROUGH THE WEEKEND WITH LONGER PERIOD SWELL INDUCING SUSTAINED RUNUP. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... TROPICAL STORM SANDY CENTERED NEAR 13.8N 77.8W AT 1500 UTC AND CONTINUES TO SHOW IMPROVED STLT SIGNATURE PAST 12 HOURS...WITH DEEP CNVTN IMPROVING NEAR CORE. PRESENTLY...SSW TO S FLOW ON E SEMICIRCLE OF SANDY GENERATING LARGEST SEAS...WITH WAVE MODELS NOT HANDLING INITIAL STAGES OF STORM WELL YET. NAH VERSION OF WW3 LIKELY BEST AT INITIAL CONDITIONS...ALBEIT A BIT TO THE E OF PRESENT POSITION. LARGE WIND FIELD OF SANDY WILL PRODUCE BROAD CYCLONIC WIND FIELD AFFECTING THE ENTIRE BASIN W OF 63W BY THU...WITH SLY FLOW AND ASSOCIATED WIND SWELL LIFTING N WITH AND AFTER SANDY TO AFFECT CARIB COASTS OF HISPANIOLA STRONGLY. ACCELERATED SLY FLOW SHOULD BE EXPECTED THROUGH WINDWARD AND MONA PASSAGES THU NIGHT AND FRI. CONVERGENCE LINES OR A TAIL OF SANDY WILL LIFT N BEHIND SANDY'S EXIT THU THROUGH FRI...AND ADD TO TORRENTIAL RAINS EXPECTED ACROSS JAMAICA AND CUBA...AND AFFECT LAND AREAS BETWEEN 78W OVER CUBA AND HISPANIOLA... POSSIBLY TO INCLUDE JAMAICA. SANDY WILL LEAVE A VERY LARGE AND STRONG FOOT PRINT ACROSS THE REGION DURING THE NEXT SEVERAL DAYS! NOTE...GRIDDED MARINE FORECAST IS AVAILABLE AT WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE GULF OF MEXICO... .NONE. CARIBBEAN SEA AND TROPICAL N ATLC... .HURRICANE WARNING ZONE AMZ021. .TROPICAL STORM WARNING ZONES AMZ021-031. SW N ATLANTIC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ FORECASTER STRIPLING