000 AGXX40 KNHC 020543 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 143 AM EDT FRI MAY 2 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: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. LATEST MWW3 BLENDED WITH PREVIOUS/OFFICIAL FORECAST. MEDIUM CONFIDENCE TODAY...HIGH CONFIDENCE THEREAFTER. ARRAY OF MODEL GUIDANCE IS CLOSE AGREEMENT. A STATIONARY FRONT EXTENDS FROM TAMPA BAY TO THE CENTRAL BAY OF CAMPECHE WITH A PRE- FRONTAL TROUGH EXTENDING NNE FROM THE YUCATAN CHANNEL TO SW FL. IT IS POSSIBLE THAT A SURFACE LOW...OR LOWS...MAY DEVELOP AND RACE NE ALONG THE QUASI-STATIONARY FRONT TODAY INTO SAT. ASSOCIATED CONVECTION HAS DECREASED SIGNIFICANTLY OVER THE PAST FEW HOURS...BUT ABUNDANT DEEP LAYERED MOISTURE CONTINUES TO LIFT N AND NE ACROSS THE AREA. EXPECT LITTLE CHANGE IN THIS MOISTURE SOURCE AS AN UPSTREAM SHORTWAVE IS STILL DIGGING SE ACROSS NORTHERN MEXICO AND AN UPPER RIDGE CENTRAL AMERICA IS ONLY JUST BEGINNING TO COLLAPSE SE. WILL FORECAST SCT RW/ISOL TS ACROSS CENTRAL AND E GULF WATERS TODAY...WITH MANUAL ADJUSTMENTS TO GRIDS FOR BOTH AREAL COVERAGE AND INTENSITY LIKELY DURING THE DAY AS HEATING KICKS OFF CLUSTERS. N-NE WINDS ARE AT 15-20 KT W OF THE FRONT...WITH ONLY SMALL PATCHES OF 20-25 KT...EXCEPT NE-E WINDS AT 10-15 KT ARE NOTED ACROSS THE NW AND N-CENTRAL WATERS. A SURFACE HIGH WILL MOVE OFF THE TX COAST THIS AFTERNOON AND WILL TIGHTEN THE GRADIENT SUPPORTING NNE 20-25 KT ACROSS THE SW WATERS BRIEFLY THIS EVENING WHILE PUSHING THE WEAKENING FRONT E AGAIN AND THROUGH THE FL STRAITS ON SAT NIGHT. THE SURFACE HIGH WILL WILL BE POSITIONED S OF THE MS DELTA ON SUN NIGHT SETTING UP SLY 10-15 KT RETURN FLOW OVER THE NW WATERS. AS THE HIGH SHIFTS E OVER NE GULF ON MON THE 10-15 KT E-SE RETURN FLOW WILL SPREAD E ACROSS THE ENTIRE AREA S AND SW OF THE HIGH. THE GRADIENT WILL TIGHT AND INCREASE THE WINDS TO 15-20 KT ACROSS THE NW AND W-CENTRAL PORTION ON TUE NIGHT INTO WED. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. FOR WAVES USED A BLEND OF THE LATEST MWW3 WITH PREVIOUS/ OFFICIAL FORECAST. HIGH CONFIDENCE. THE ATLC RIDGE IS ACROSS THE NORTHERN BAHAMAS SUPPORTING NE-E 20- 25 KT/SEAS 7-9 FT OVER THE S-CENTRAL CARIBBEAN WATERS. ELSEWHERE...MODERATE ELY TRADES WITH SEAS OF 4-7 FT. A WEAKENING COLD FRONT WILL MOVE INTO THE NW CARIBBEAN ON SAT NIGHT...BUT QUICKLY LOSE IDENTITY. BY THEN...THE ATLC RIDGE WILL HAVE SHIFTED S ACROSS THE SOUTHERN BAHAMAS RELAXING THE GRADIENT WITH ONLY ELY 15-20 KT TRADES EXPECTED ACROSS THE CARIBBEAN S OF 17N AND E OF 82W...AND ELY 10-15 KT WINDS ELSEWHERE. LITTLE CHANGE THEN EXPECTED THROUGH THE REMAINDER OF THE PERIOD. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. LATEST MWW3 BLENDED WITH PREVIOUS/OFFICIAL FORECAST. MED-HIGH CONFIDENCE. MODEL GUIDANCE IN FAIRLY CLOSE AGREEMENT. A STATIONARY FRONT IS JUST OFFSHORE THE NE FL COAST WITH A SQUALL LINE ABOUT 120 NM TO THE E OF THE FRONT. THE ASSOCIATED CONVECTION IS DECREASING AS THE SQUALL LINE MOVES E OF THE MAXIMUM GULF STREAM TEMPS. A RIDGE EXTENDS FROM BERMUDA TO PORT CANAVERAL. A 120 NM WIDE FRONTAL TROUGH ACCOMPANIED BY LOCALLY OVC LOW-MID LEVEL CLOUDS IS STILL EVIDENT ALONG THE SOUTHERN PERIPHERY OF THE ANTICYCLONIC FLOW...FROM NEAR 18N60W TO THE SE BAHAMAS NEAR 23N74W. THE RIDGE WILL WEAKEN TODAY ALLOWING THE COLD FRONT TO PROGRESS A FEW HUNDRED NM E BEFORE STALLING BRIEFLY THIS EVENING. A REINFORCING SURGE WILL GET THE FRONT MOVING E AGAIN LATE TONIGHT...OR EARLY SAT MORNING...WITH THE FRONT REACHING A PSN FROM BERMUDA TO THE CAY SAL BANK ON SUN AFTERNOON. MAY SEE A WEAK SURFACE LOW RACE NE ALONG THE FRONT ON SAT NIGHT. EXPECT A SW-W 15-20 KT WIND SHIFT ALONG THE FRONT ACROSS THE WATERS N OF 30N BUT ONLY A 10-15 KT SLY WINDS TO THE S OF 30N E OF THE FRONT. THE POST-FRONTAL RIDGE WILL BUILD E ACROSS N FL ALONG 29N THROUGH MON. A SURFACE HIGH WILL SHIFT E ALONG THE RIDGE AXIS ON MON NIGHT AND TUE RE-ORIENTATING THE RIDGE FROM E TO W ACROSS N-CENTRAL FL ON TUE. BY THEN THE SOUTHERN SEGMENT OF THE FRONT WILL HAVE STALLED FROM 27N60W TO THE WINDWARD PASSAGE. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 NELSON. NATIONAL HURRICANE CENTER.