000 AGXX40 KNHC 151842 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 242 PM EDT WED AUG 15 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... WESTERN EXTENSION OF ATLC RIDGE EXTENDS ACROSS S CENTRAL FLORIDA AND INTO ERN GULF AND THEN WWD TO TEXAS COASTAL WATERS...WITH LITTLE SIGNIFICANT CHANGE IN ALIGNMENT NEXT FEW DAYS. ANTICYCLONIC FLOW PRESENTLY ACROSS BASIN...WITH WINDS 10 KT OR LESS AND SEAS 2 FT OR LESS N OF 23N AND E OF 93W...WINDS NEAR 15 KT AND SEAS NEAR 3 FT W AND SW PORTIONS. TUTT LOW OVER W CENTRAL GULF NEAR 24N93.5W DRIFTING SW AND WEAKENING...BUT STILL PROVIDING MOISTURE AND TURNING FOR INSTABILITY TO THE E AND NE OF LOW. ENERGETIC TROPICAL WAVE ACROSS W CARIB AND CENTRAL AMERICA TO MOVE MORE W-NW NEXT 48 HOURS BEFORE BECOMING BECOMING ABSORBED IN LOW LEVEL TROUGHING OVER MEXICO. MODELS...AND GFS IN PARTICULAR...DEVELOP LOW PRES ACROSS EXTREME SW GULF...PARTIALLY INDUCED BY MECHANICAL FORCING FROM OROGRAPHIC EFFECTS AND SEMI-PERMANENT COASTAL TROUGH. NHC MID RANGE GUIDANCE INDICATING SURFACE LOW TO EVENTUALLY BE LEFT BEHIND BY LOW LINGERING OFFSHORE OF MEXICAN COAST BETWEEN 19N AND 21N THROUGH DAY 3...THEN DRIFTING NORTHWARD AND PARALLEL TO COAST NEXT FEW DAYS. SOUTHWEST NORTH ATLC S OF 31N W OF 65W... REMNANTS OF T.D. 7 DRIFTING N ALONG 54W ATTM AND SEVERING ATLC RIDGE FROM W EXTENSION INTO FLORIDA. LIGHT TO MODERATE WIND FLOW AND SEAS THUS PREVAIL ACROSS THE WATERS...WITH WEAK LLVL TROUGHING EXTENDING SE FROM REMNANTS OF T.D. 7 TO THE NE CARIB. AS THESE TROPICAL REMNANTS LIFT N OF 30N NEXT 24 HOURS AND MOVE OVER RIDGE...HIGH WILL REORGANIZE A BIT TO THE S AND ALONG ABOUT 27N...MAINTAINING WEAK RIDGING ACROSS THE WATERS NEXT FEW DAYS. HIGHEST WINDS AND SEAS TO PERSIST THROUGH SOUTHERN CORRIDOR OF THE BAHAMAS AND N OF THE GREATER ANTILLES. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... WIND SURGE ACROSS WRN THIRD OF BASIN ASSOCIATED WITH TROPICAL WAVE HAS WEAKENED SLIGHTLY PAST 12 HOURS...WITH WINDS NEAR 20 KT AND SEAS 6-8 FT FROM 14N-18N AND W OF 79W. TYPICAL BROAD ZONE OF 20 KT WITH SMALL POCKETS TO 25 KT OFFSHORE OF COLOMBIA PREVAILS IN CENTRAL CARIB. A TROPICAL WAVE IS ON OUR SURFACE MAPS ACROSS THE ERN CARIB...BUT ANY AEW ENERGY ASSOCIATED WITH THE FAR S PORTION OF THE FORMER T.D. 7 WOULD BE MINIMAL...AND SOME OF THE APPARENT SIGNAL IS LIKELY INDUCED INVERTED TROUGHING. THUS DO NOT EXPECT MUCH EFFECT ON WIND AND SEAS WITH THIS PARTICULAR WAVE. THESE TWO FEATURE WILL SHIFT W NEXT 48 HOURS AND MAINTAIN MARINE CONDITIONS NEAR STATUS QUO. VERY BROAD CYCLONIC TURNING SEEN ACROSS CENTRAL ATLC IN LOW CLOUDS...AND I AM OF THE OPINION THAT THIS MAY BE THE NORTHERN VORT AND ASSOCIATED LLVL WIND SURGE AND SAL THAT IS PART OF A LARGE AEW COMPLEX LINGERING FARTHER TO THE E. W AFRICAN SOUNDINGS SUGGEST TWO PERTURBATIONS LEAVING THE CONTINENT BACK TO BACK. THIS FEATURE ALSO DEPICTED ON OUR SURFACE MAPS AS A TROPICAL WAVE AND WILL RACE W AT 10 DEGREES OR MORE NEXT FEW DAYS...REACHING THE LESSER ANTILLES BY 12Z FRI...WITH SIGNAL IN THE MODELS THEN DIFFICULT TO FOLLOW. REGARDLESS...THIS LLVL WIND SURGE WILL MOVE INTO THE TROPICAL ATLC WATERS BY TOMORROW AFTERNOON AND THROUGH THE CARIBBEAN FRI THROUGH SUN. AS LLVL WIND SURGE AND SHALLOW MOISTURE HITS THE NE CARIB ISLANDS FRI NIGHT AND SAT...BRIEF BUT STRONG CONVECTION WITH GUSTY WINDS WILL OCCUR. OTHERWISE TYPICAL TRADES TO AROUND 20 KT ACROSS THE S CENTRAL CARIBBEAN. NOTE...GRIDDED MARINE FORECAST IS AVAILABLE AT WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE GULF OF MEXICO... .NONE. CARIBBEAN SEA... .NONE. SW N ATLANTIC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ FORECASTER STRIPLING