000 AGXX40 KNHC 140712 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 312 AM EDT MON SEP 14 2015 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. NWPS BLENDED WITH PREVIOUS OFFICIAL FOR WAVES. HIGH CONFIDENCE. A THERMAL TROUGH WILL DEVELOP EACH AFTERNOON OVER THE YUCATAN PENINSULA. THE TROUGH WILL MOVE W-NW INTO THE SW GULF WATERS DURING THE EVENING THROUGH LATE NIGHT HOURS...THEN DISSIPATE BY LATE MORNING. THE STRONGER GFS SEEMS REASONABLE HERE. IT BRIEFLY CARRIES 20-25 KT WINDS ALONG THE NW COAST OF THE YUCATAN PENINSULA TONIGHT WHEN RIDGING TO THE N WILL FORCE A SLIGHTLY STRONGER PRESSURE GRADIENT. A STATIONARY FRONT WAS ANALYZED FROM SANIBEL ISLAND FLORIDA THROUGH 24N96W TO 1010 MB LOW PRES JUST OFFSHORE OF CABO ROJO MEXICO. THE BOUNDARY IS EXPECTED TO SHIFT SLIGHTLY FARTHER S ACROSS THE CENTRAL GULF TODAY AND DISSIPATE TONIGHT AS THE SUPPORTING UPPER LEVEL TROUGH PULLS NORTHEASTWARD. THE LOW PRES SYSTEM IS FORECAST TO MEANDER IN THE SAME AREA TODAY BEFORE DISSIPATING TONIGHT. THE UPPER PATTERN OVER THE GULF WILL BECOME MORE AMPLIFIED TUE AS A SHARP TROUGH PUSHES W INTO THE CENTRAL GULF. AT THE SURFACE...A N TO S TROUGH IS EXPECTED OVER THE EASTERN GULF BY TUE NIGHT AND SHOULD MIGRATE W TO AROUND 88W BY THU BEFORE SHIFTING SLIGHTLY E ON FRI. OTHER THAN ALONG THE N COAST OF THE YUCATAN TONIGHT...AT NO TIME DURING THE FORECAST PERIOD ARE WINDS AND SEAS EXPECTED TO EXCEED THE ADVISORY CRITERIA OF 20-25 KT AND 8 FT...RESPECTIVELY. THERE APPEARS TO BE NO SIGNIFICANT REASON TO STRAY FROM THE GFS FORECAST. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: 00Z GFS BLENDED WITH PREVIOUS OFFICIAL. NWPS BLENDED WITH PREVIOUS OFFICIAL FOR WAVES. MEDIUM CONFIDENCE. THE 0222Z ASCAT-B PASS SHOWED A SOLID AREA OF 20-25 KT WINDS ALONG THE NW COAST OF VENEZUELA BEHIND A TROPICAL WAVE AND ALONG THE S CENTRAL COAST OF HISPANIOLA. NONE OF THE MODELS WERE STRONG ENOUGH WITH THESE WINDS...SO MANUAL ADJUSTMENTS WERE MADE TO THE GRIDS. THE MODELS ARE IN RELATIVELY GOOD AGREEMENT ON THE RIDGING N OF THE AREA DRIVING THE TRADE WINDS THROUGH WED. AFTER THIS TIME...THE FORECAST BECOMES MORE UNSURE. THE 00Z ECMWF HOLDS WEAKER TROUGHING OVER THE BAHAMAS THAN THE OTHER MODELS WHILE THE NAVGEM AND CMC ARE SIGNIFICANTLY STRONGER WITH THE TROUGHING. THE 00Z GFS FALLS BETWEEN THESE TWO CAMPS. THIS SEEMS REASONABLE. IT WAS USED TO ADJUST THE GRIDS WHICH CALL FOR WINDS AND SEAS TO DROP BELOW ADVISORY CRITERIA WED AS THE PRESSURE GRADIENT WEAKENS. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL. NWPS BLENDED WITH PREVIOUS OFFICIAL FOR WAVES. HIGH CONFIDENCE. THE 0224 UTC ASCAT PASS SHOWED FRESH TO STRONG SE WINDS IN THE TURKS AND CAICOS AND FAR SE BAHAMAS SOUTHWARD TO N CENTRAL HISPANIOLA. THE GFS WAS THE ONLY 00Z MODEL TO PICK UP ON THIS. USED ITS FORECAST HERE TO ADJUST THE GRIDS. WINDS SHOULD PULSE TO A FRESH TO STRONG BREEZE ALONG THE N COAST OF HISPANIOLA. THESE WINDS HAVE BEEN ENHANCED BY THE INCREASED PRESSURE GRADIENT BETWEEN THE TROPICAL WAVE JUST W OF THIS REGION AND HIGH PRES TO THE N. AS THE WAVE MOVES AWAY...LOOK FOR WINDS TO DROP BELOW ADVISORY CRITERIA BY TUE. A STATIONARY FRONT WAS ANALYZED FROM 31N76W TO VERO BEACH FLORIDA. THE PORTION OF THE BOUNDARY S OF 30N WILL DISSIPATE OVERNIGHT TONIGHT WHILE THE REMAINDER PUSHES E AS A COLD FRONT. RIDGING N OF THE AREA WILL DOMINATE THE FLOW ELSEWHERE. AS STATED ABOVE...THE 00Z ECMWF HOLDS WEAKER TROUGHING OVER THE BAHAMAS THAN THE OTHER MODELS WHILE THE NAVGEM AND CMC ARE SIGNIFICANTLY STRONGER WITH THE TROUGHING. THE 00Z GFS FALLS BETWEEN THESE TWO CAMPS. THIS SEEMS REASONABLE. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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.