000 AGXX40 KNHC 121748 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 148 PM EDT SUN MAY 12 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 INTO PREVIOUS GRID PACKAGE A COLD FRONT EXTENDS FROM THE FL BIG BEND TO THE MEXICAN COAST AT 20N97W. WIDESPREAD RAIN WITH EMBEDDED ISOLATED SHOWERS IS CURRENTLY NOTED W OF THE FRONT WHILE A 30 NM WIDE BAND OF SHOWERS AND TSTMS DEFINE THE FRONTAL BOUNDARY ACROSS THE CENTRAL GULF OF MEXICO...BUT NOT AS WELL DEFINED OVER THE W-CENTRAL WATERS. A PRE-FRONTAL TROUGH HAS MOVED OVER CENTRAL INTERIOR FL AND HAS RECENTLY SET OFF A LINE OF SHOWERS AND TSTMS ENHANCED BY THE=W COAST SEABREEZE. STILL EXPECT THE SEGMENT OF THE FRONT TO THE N OF 26N TO CONTINUE E ACROSS FL LATE TONIGHT INTO MON. THE FORECAST FOR THE SEGMENT OF THIS FRONT TO THE S OF 26N IS NOT AS CERTAIN AS THE FRONT IS WEAK AND A TROUGH ALREADY IS MEANDERING IN THE BAY OF CAMPECHE. GENERALLY EXPECT THIS SOUTHERN PORTION OF THE FRONT TO LOSE MUCH OF ITS SE PROGRESSION AND HANGING UP FROM SE FL ACROSS THE NW YUCATAN PENINSULA TO THE CENTRAL BAY OF CAMPECHE ON TUE. THE FAR W PORTION OF THIS FRONTAL TROUGH THEN MERGES WITH THE TROUGH AND BECOMES ORIENTATED N-S ACROSS THE BAY OF CAMPECHE...AND GRADUALLY DISSIPATES THROUGH WED EVENING. THE GFS AND ECMWF ARE FAIRLY CLOSE IN AGREEMENT WITH THE TIMING...AND NOW DIFFER ONLY SLIGHTLY CONCERNING THE STRENGTH OF THE NE FLOW W OF THE FRONT ACROSS THE W-CENTRAL GULF. HIGH PRESSURE WILL REBUILD ACROSS THE NW GULF BEGINNING LATE TONIGHT WITH THE ASSOCIATED RIDGE ORIENTATED NW-SE FROM LA TO THE DRY TORTUGAS. AS THE PARENT HIGH SHIFTS E ACROSS THE SE CONUS THE RIDGE BECOMES ORIENTATED N-S FROM LA TO THE YUCATAN ON TUE NIGHT...EXTENDS FROM THE FL BIG BEND TO THE NE TX COAST ON WED...AND FROM CEDAR KEY FL TO THE MS DELTA ON THU. SOUTHERLY RETURN FLOW SETS UP AT 10-15 KT ACROSS THE NW GULF LATE MON NIGHT WITH THESE CONDITIONS SPREADING E ACROSS THE ENTIRE GULF WED NIGHT WITH GUIDANCE SUGGESTING E WINDS AT 15-20 KT ACROSS THE FL STRAITS ON WED. BLENDED LATEST GFS AND ECMWF INTO PREVIOUS OFFICIAL GRIDS. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: GFS/ECMWF BLEND INTO PREVIOUS GRID PACKAGE A DEEP LAYERED TROUGH IS SWINGING E ACROSS THE NE CARIBBEAN WHILE LEAVING A LOW LEVEL TROUGH ACROSS PUERTO RICO AND EFFECTIVELY MAINTAINING LIGHT WINDS ACROSS THE NE CARIBBEAN TODAY. THIS TROUGH WILL DRIFT W REACHING FROM THE SE BAHAMAS TO THE WINDWARD PASSAGE ON MON. A FRESH TO STRONG BREEZE...20-25 KT...WILL CONTINUE WITHIN 240 NM OF THE NW COAST OF COLOMBIA THROUGH THE PERIOD. E WINDS CURRENTLY AT 15-20 KT...WITH SEAS 4-6 FT...ACROSS THE GULF OF HONDURAS SHOULD DIMINISH TO 15 KT BY THIS EVENING. A WEAK COLD FRONT...ACCOMPANIED BY E WINDS AT 10 KT BACKING GRADUALLY TO THE NE...WILL PASS E ACROSS THE CUBAN WATERS N OF 20N ON MON INTO EARLY TUE AND ABSORB WHATEVER REMAINS OF THE TROUGH IN THE VICINITY OF THE WINDWARD PASSAGE. HIGH PRESSURE BUILDING ACROSS THE GULF OF MEXICO WILL SPREAD SE AND INCREASE THE NE FLOW TO 15-20 KT...WITH SEAS 3-5 FT...ACROSS THE W CARIBBEAN ON TUE...WED AND INTO EARLY THU. OTHERWISE MODERATE TO FRESH EASTERLY TRADES WILL PERSIST ELSEWHERE THROUGH THE PERIOD EXCEPT INTERRUPTED BY THE SOUTHERN EXTENSION OF COLD FRONT PASSING THROUGH THE N-CENTRAL CARIBBEAN ON TUE-WED AND DECAYING ACROSS THE VIRGIN ISLANDS ON THU-FRI. BLENDED LATEST GFS AND ECMWF INTO PREVIOUS GRIDS AND ALSO MANUALLY ADJUSTED WINDS WHERE APPROPRIATE ALONG COAST OF COLOMBIA. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: GFS-ECMWF BLEND INTO PREVIOUS GRID PACKAGE THE 1012 MB LOW PRES CENTER NEAR 22.5N67W HAS DECOUPLED FROM THE MID-UPPER CYCLONE CURRENTLY NEAR 22N61W...BUT CONTINUES TO SPIN ALONG A TROUGH EXTENDING N-S FROM PUERTO RICO TO 28N67W. BUOY AND SHIP REPORTS INDICATE WINDS/SEAS ARE DIMINISHING/SUBSIDING BUT ALL OF THE LATEST GUIDANCE HANGS ONTO ENOUGH OF A CIRCULATION THAT A 1014 MB LOW IS FORECAST ALONG THE WESTWARD DRIFTING TROUGH NEAR 23N69W EARLY MON...BUT ONLY ACCOMPANIED BY 5-10 KT WINDS. THE GRADIENT WELL NE OF THE DISSIPATING LOW TO 55W WILL MAINTAIN E-SE WINDS AT 20-25 KT THROUGH LATE TONIGHT...DIMINISHING TO 15-20 KT AS THE WINDS CLOCK TO S AS A COLD FRONT APPROACHES. THE TROUGH WILL WEAKEN AS IT REACHES ALONG 70W LATE MON...THEN MEANDER UNTIL ABSORBED BY THE COLD FRONT. THIS COLD FRONT WILL MOVE OFF THE SE GA/NE FL COAST THIS AFTERNOON REACHING FROM 31N75W TO THE FL STRAITS MON...AND REACH FROM BERMUDA TO THE SE BAHAMAS TUE MERGING WITH REMNANTS OF THE TROUGH. A BAND OF N-NE WINDS AT 15-20 KT IS FORECAST WITHIN 480 NM W OF THE FRONT THROUGH THU. THE MERGED FRONT WILL CONTINUE E REACHING FROM 31N60W TO THE MONA PASSAGE ON WED...FROM 31N56W TO PUERTO RICO ON THU...THEN WASH OUT FROM 26N55W TO THE MONA PASSAGE ON FRI. CONTINUED PRACTICE OF BLENDING SOME ECMWF WITH GFS INTO PREVIOUS GRIDDED PACKAGE. .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 NELSON. NATIONAL HURRICANE CENTER.