000 AGXX40 KNHC 080658 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 258 AM EDT THU MAY 8 2014 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W...AND THE SW N ATLANTIC INCLUDING THE BAHAMAS. ...GULF OF MEXICO... MODEL PREFERENCE: PREVIOUS FORECAST ADJUSTED FOR GFS FOR WIND AND MWW3/NWPS FOR WAVES. HIGH CONFIDENCE. SHIP C6SE8 SAW 25 KT E-SE WINDS AND 9 FT SEAS WHILE TRAVELING THROUGH THE STRAITS OF FLORIDA AT 0000 UTC. THE MODELS ARE WEAK WITH THE WINDS AND 3-5 FEET TOO LOW WINDS SEAS WHERE THE WIND IS BATTLING THE SWIFT CURRENT IN THE STRAITS. ADJUSTMENTS WERE MADE HERE ACCORDINGLY. OTHERWISE...THE MODELS NOW SHOW REASONABLE AGREEMENT ON THE RIDGE CENTERED ALONG THE NORTHERN GULF COASTAL PLAIN TO DOMINATE THE LARGE SCALE FLOW THROUGH MON. THE INFLUENCE OF THE POTENTIAL TROPICAL CYCLONE IN THE EASTERN PACIFIC ON THE GULF OF MEXICO FORECAST SEEMS TO BE WANING AS THE MODELS GENERALLY AGREE ON PICKING THE SYSTEM UP PIECEMEAL AND STREAMING ITS REMNANTS OVER THE WESTER GULF LATE TODAY INTO FRI WITH LITTLE FANFARE. THE GFS SUGGESTS THE GRADIENT WILL REMAIN MODEST ACROSS BASIN WITH ONLY LOCAL EFFECTS ALLOWING WINDS TO REACH A FRESH TO STRONG BREEZE. GOING WITH GFS SOLUTION THROUGH MON SEEMS REASONABLE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: PREVIOUS FORECAST ADJUSTED FOR GFS/ECMWF BLEND FOR WIND...FAVORING THE GFS IN THE WESTERN CARIBBEAN. WAVES ADJUSTED FOR THE MWW3/NWPS. MEDIUM CONFIDENCE. THE 0330 UTC ASCAT PASS OVER THE GULF OF HONDURAS SHOWS WINDS TO 30 KT...5 KT HIGHER THAN THE GFS AND 10 KT HIGHER THAN THE 12Z ECMWF. SHIP 3ETA8 REPORTED 30 KT WITH 10 FOOT SEAS AT 0600 UTC. THE MODELS ARE OBVIOUSLY LOW HERE AND LIKELY WILL CONTINUE TO BE INTO THE FORECAST PERIOD WITH A SIMILAR PATTERN EXPECTED OVER THE GULF OF HONDURAS THROUGH MON. THE STRONGER GFS WILL BE RELIED ON HERE AS WELL AS WITH OTHER AREAS WHERE LOCAL EFFECTS ARE DRIVING STRONGER WINDS. THE 0150 UTC ASCAT SHOWED A SIZABLE AREA OF 25 KT WINDS IN THE WINDWARD PASSAGE WHILE THE GFS AND ECMWF ONLY SHOW WINDS TO 20 KT. WINDS WERE BUMPED UP HERE THROUGH SUN WHILE THE WIND DIRECTION SUPPORTS FUNNELING INTO THE PASSAGE. FARTHER E...THERE IS AGREEMENT THAT THE MEAN TROUGH OVER THE WESTERN ATLC WILL PINCH OFF AN UPPER LOW JUST N OF THE AREA BEGINNING FRI. THE GFS CONTINUES TO CARRY THE UPPER LOW OVER THE ATLC JUST N OF THE VIRGIN ISLANDS SAT WHILE THE ECMWF DIGS THE LOW FARTHER SW OVER THE NE CARIBBEAN. THE GFS AND ECMWF RESPECTIVE ENSEMBLE MEANS FAVOR THEIR OPERATIONAL RUNS. THE UKMET MORE CLOSELY RESEMBLES THE GFS WHILE THE NAVGEM LOOKS MORE LIKE THE ECMWF ALOFT. AT THE SURFACE...WINDS BECOME A GENTLE BREEZE BY SAT AS THE INVERTED TROUGH OVER THE NE CARIBBEAN TAKES HOLD AND THE TIGHTEST PRESSURE GRADIENT SHIFTS N OF THE AREA. THE ECMWF DIMINISHES THE WINDS SLIGHTLY FASTER AND CARRIES A MORE EASTERLY INVERTED TROUGH OVER THE AREA...BUT THE WIND AND WAVE SENSIBLE DIFFERENCES ARE REASONABLY SMALL. A BLEND OF THE MODELS PROVIDES A COMPROMISE TROUGH POSITION IN LINE WITH THE GLOBAL MODEL CONSENSUS. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: PREVIOUS FORECAST ADJUSTED FOR GFS/ECMWF BLEND FOR WIND AND MWW3/EC WAVE FOR WAVES. LOW CONFIDENCE. THERE IS AGREEMENT THAT THE MEAN TROUGH OVER THE WESTERN ATLC WILL PINCH OFF AN UPPER LOW JUST N OF THE AREA BEGINNING FRI. THE GFS CONTINUES TO CARRY THE UPPER LOW OVER THE ATLC JUST N OF THE VIRGIN ISLANDS SAT WHILE THE ECMWF DIGS THE LOW FARTHER SW OVER THE NE CARIBBEAN. THE GFS AND ECMWF RESPECTIVE ENSEMBLE MEANS FAVOR THEIR OPERATIONAL RUNS. THE UKMET MORE CLOSELY RESEMBLES THE GFS WHILE THE NAVGEM LOOKS MORE LIKE THE ECMWF ALOFT. AT THE SURFACE...THE MODELS HAVE TRENDED WEAKER WITH THE INVERTED TROUGH ASSOCIATED WITH THIS UPPER LOW AND THE GFS NO LONGER SUPPORTS A CLOSED LOW LEVEL CIRCULATION MOVING INTO THE BAHAMAS MON...FAVORING AN ELONGATED LOW EMBEDDED ALONG THE TROUGH. LIKE AT THE SURFACE...THE GFS/UKMET ARE MORE EASTERLY WITH THIS INVERTED TROUGH THAN THE ECMWF/NAVGEM BY SUN...MAKING FOR NEARLY A 5 DEGREE DIFFERENCE IN THE LONGITUDE OF THE TROUGH OVER THE BAHAMAS BY MON NIGHT. CONFIDENCE IS VERY LOW. A BLEND OF THE GFS AND ECMWF AND THEIR RESPECTIVE WAVE MODELS WAS USED TO ADJUST THE WIND DIRECTION AND WIND MAGNITUDES WERE BUMPED UP TO ACCOUNT FOR THE BLENDING. IMPORTANT TO NOTE THAT THE 00Z GFS ALREADY CARRIED A SMALLER AREA OF 25 KT WINDS ON THE NORTHERN EDGE OF THE INVERTED TROUGH SUN ONWARD COMPARED TO THE RUN LAST NIGHT. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANE WARNINGS.GOV/MARINE $$ .FORECASTER SCHAUER. NATIONAL HURRICANE CENTER.