000 AGXX40 KNHC 150744 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 244 AM EST FRI NOV 15 2013 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: GFS-ECMWF BLEND WITH PREVIOUS FORECAST FOR WINDS. BLEND OF PREVIOUS FORECAST...MWW3...AND NWPS FOR WAVES. MEDIUM CONFIDENCE. THE MODELS AGREE ON LIFTING THE TAIL END OF THE SURFACE BOUNDARY CURRENTLY OVER THE SOUTHERN GULF NORTHWARD AS A WARM FRONT OVER THE NEXT TWO DAYS WITH AN AREA OF CONCENTRATED CONVECTION EXPECTED IN THE EASTERN GULF. HOWEVER...THERE ARE DIFFERENCES IN THE DETAILS. THE GFS LIKELY HAS GRID-SCALE FEEDBACK ISSUES HERE AS IT STAMPS OUT OVER 3 INCHES OF PRECIPITATION FOR BOTH THE 12-18Z PERIOD TODAY AND 18Z-00Z PERIOD TONIGHT WITH LITTLE ATTRIBUTABLETO CONVECTION. THE ECMWF ALSO HAS SIMILAR BULLSEYES BUT IS NOT QUITE AS ENTHUSIASTIC. GIVEN THE UNCERTAINTY IN THE DETAILS...BLENDING THE MOST RECENT GFS AND ECMWF WITH THE PREVIOUS FORECAST SEEMS PRUDENT. THE GFS GENERATES 30 KT WINDS AT 16/00Z IN THE NE GULF NEAR THE VORT IMPACTED BY THE GRID-SCALE FEEDBACK. THE ECMWF HAS A SIMILAR WIND FIELD AND TIMING OF THE WARM FRONT WITH LIGHTER WINDS. THE NEXT COLD FRONT REACHES THE GULF MON. THE GFS AND ECMWF ARE SIMILAR WITH THE TIMING OF THE FRONT MON...BUT THE ECMWF HAS STRONGER WINDS BEHIND THE BOUNDARY IN THE NW GULF MON NIGHT. BY TUE...THE ECMWF PUSHES THE BOUNDARY S THROUGH THE WESTERN GULF WHILE THE GFS HANGS IT CONSIDERABLY FARTHER N. THE UKMET SHOWS BETTER AGREEMENT WITH THE ECMWF WITH THE STRENGTH OF THE WINDS BEHIND THE FRONT MON AND TURNS THE WINDS NW IN THE SW GULF LIKE THE ECMWF TUE...ALBEIT NOT AS STRONG. CONFIDENCE IS LOW IN THE DETAILS HERE. A BLEND OF THE GFS/ECMWF CONTINUES TO ACCOUNT FOR UNCERTAINTY. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 65W... MODEL PREFERENCE: CARIBBEAN - LATEST GFS AND MWW3 BLENDED WITH PREVIOUS FORECAST. HIGH CONFIDENCE. TROPICAL N ATLC - GFS-ECMWF BLEND WITH PREVIOUS FORECAST FOR WINDS. BLEND OF PREVIOUS FORECAST...MWW3...AND NWPS FOR WAVES. MEDIUM CONFIDENCE. THE 0150 ASCAT AND 0406 OSCAT PASSES SHOW A SIZABLE AREA OF 25 KT WINDS OFF THE COAST OF COLOMBIA. AS USUAL...THE GFS IS DOING A BETTER JOB CAPTURING THE STRONG WINDS. THE 0150 UTC CRYOSAT PASS SHOWS 8-9 FT SEAS ACROSS THE AMZ031 ZONE...WITH BUOY 42056 ALSO SHOWING 8 FT AND 21 KT. THESE CONDITIONS ARE IN BEST AGREEMENT WITH THE MWW3 COMPARED TO THE LOWER HEIGHTS FROM THE EC WAVE MODEL AND HIGHER VALUES FROM THE UKMET WAVE. THE GFS WAS USED TO ADJUST THE FORECAST IN THE SHORT TERM AND SEEMS LIKE A REASONABLE CHOICE FOR THE LONG RANGE AS WELL. HIGH PRES WILL SHIFT NE OFF THE E COAST OF U.S. AND BRING A RETURN OF MORE MODERATE EASTERLY FLOW ACROSS MOST OF BASIN INTO SAT WITH FRESH FLOW FOUND IN THE S CENTRAL PORTIONS. THE REMNANTS OF THE OLD ATLC FRONTAL BOUNDARY WILL MOVE SW ACROSS NE CARIBBEAN ISLANDS SUN IN A BACK DOOR FASHION. NW TO N SWELL GENERATED BEHIND THIS FRONT WILL MOVE INTO CARIBBEAN PASSAGES STARTING EARLY FRI AND INTO E CARIBBEAN THROUGH EARLY SAT THEN VEER MORE N TO NE INTO SUN...WITH PEAK SEAS AROUND 7-8 FT MONA PASSAGE AROUND 00Z SAT PER THE MWW3. IN THE TROPICAL N ATLC...A LINGERING SURFACE BOUNDARY N OF THE AREA WILL DEVELOP A WAVE THIS WEEKEND THAT THE MODELS AGREE ON DEEPENING TO AROUND 1000 MB BY MON. THERE IS CONSIDERABLY GOOD AGREEMENT ON THE LOCATION OF THIS LOW BETWEEN THE GFS...ECMWF...NAVGEM AND UKMET THROUGH THE END OF THE FORECAST PERIOD...WITH THE UKMET THE DEEPEST SOLUTION AND THE NAVGEM THE WEAKEST. A BLEND OF THE ECMWF AND GFS SEEMS REASONABLE WHEN BLENDED WITH THE PREVIOUS FORECAST. THIS ALLOWS FOR LIGHT TO MODERATE WINDS OVER THE TROPICAL N ATLC SW OF THE LOW AND SEAS GENERALLY IN THE 5-7 FT RANGE. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: GFS-ECMWF BLEND WITH PREVIOUS FORECAST FOR WINDS. BLEND OF PREVIOUS FORECAST...MWW3...AND NWPS FOR WAVES. MEDIUM CONFIDENCE. SEE THE SECTION ABOVE FOR DETAILS ON THE LOW PRES SYSTEM EXPECTED IN THE CENTRAL ATLC BEGINNING THIS WEEKEND. ELSEWHERE THE ECMWF AND UKMET CARRY A WEAKER AND FASTER COLD FRONT INTO NW WATERS THAN THE GFS LATE MON INTO TUE...WITH THE GEFS FAVORING THE GFS AND THE ECMWF ENSEMBLE MEAN FAVORING THE ECMWF. THE DIFFERENCES ARE NOT LARGE ENOUGH TO CALL THIS A LOW CONFIDENCE FORECAST...BUT THERE IS NO CLEAR FAVORITE FOR THE TIMING OF THE BOUNDARY AND THE STRENGTH OF THE WIND BEHIND IT. A BLEND OF THE GFS/ECMWF WITH THE PREVIOUS FORECAST SEEMS REASONABLE FOR NOW. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... GMZ011...NONE. GMZ013...NONE. GMZ015...NONE. GMZ017...NONE. GMZ019...NONE. GMZ021...NONE. GMZ023...NONE. GMZ025...NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... AMZ011...NONE. AMZ013...NONE. AMZ015...NONE. AMZ017...NONE. AMZ019...NONE. AMZ021...NONE. AMZ023...NONE. AMZ025...NONE. AMZ027...NONE. AMZ029...NONE. AMZ031...NONE. AMZ033...NONE. AMZ035...NONE. AMZ037...NONE. AMZ039...NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... AMZ111...NONE. AMZ113...NONE. AMZ115...NONE. AMZ117...NONE. AMZ119...NONE. AMZ121...NONE. AMZ123...NONE. AMZ125...NONE. AMZ127...NONE. *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER SCHAUER. NATIONAL HURRICANE CENTER.