000 AGXX40 KNHC 240825 CCA MIMATS MARINE WEATHER DISCUSSION...CORRECTED NWS NATIONAL HURRICANE CENTER MIAMI FL 357 AM EDT WED SEP 24 2014 CORRECTED SW ATLC CONFIDENCE LEVEL 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 USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. LATEST SURFACE ANALYSIS HAS A STATIONARY FRONT EXTENDING FROM CENTRAL FLORIDA JUST N OF TAMPA SW TO 27N88W TO 26N92W TO NEAR BROWNSVILLE TEXAS. WEAK HIGH PRES IS PRESENT ELSEWHERE...EXCEPT FOR THE FAR N CENTRAL GULF WHERE HIGH PRES THERE IS STRONGER. LATEST SATELLITE-DERIVED WINDS AND BUOY DATA SHOW MODERATE NE TO E WINDS N OF 27N E OF 90W...AND ALSO FROM THE FRONT TO 28N BETWEEN 90W AND 95W WHERE THE PRES GRADIENT BETWEEN THE FRONT AND HIGH PRES TO ITS N IS THE TIGHTEST. AN ASCAT PASS FROM 0358 UTC CONFIRMED THESE WINDS OVER THE WESTERN GULF PORTION. THE OBSERVATIONS SHOW SEAS IN THE RANGES OF 1-3 FT OVER MOST ZONES...WITH THE EXCEPTION OF HIGHER SEAS OF 5-6 FT NW OF THE FRONT. SATELLITE WATER VAPOR SHOWS AMPLE DEEP LAYER MOISTURE CONFINED TO OVER THE EASTERN PORTION OF THE GULF TO THE SE OF AN UPPER TROUGH THAT STRETCHES FROM THE EASTERN U.S. SW TO 25N88W TO THE WESTERN YUCATAN PENINSULA. THIS TROUGH IS SUPPORTING THE AFOREMENTIONED STATIONARY FRONT...AND BOTH FEATURES CONTINUE TO ENHANCE ATMOSPHERIC INSTABILITY PRIMARILY TO THE SE OF THE STATIONARY FRONT WHERE SCATTERED TO NUMEROUS SHOWERS AND TSTMS ARE OBSERVED. ISOLATED SHOWERS AND TSTMS ARE OVER THE REMAINDER OF THE GULF. A WEAK INVERTED TROUGH WILL MOVE OFF THE FLORIDA COAST AND ACROSS THE EASTERN GULF THIS AFTERNOON...AND INTO FRI WHILE DISSIPATING. LOW-LEVEL MOISTURE RELATED TO THIS TROUGH IN COMBINATION WITH THAT FROM THE TROUGH ALOFT SHOULD HELP TRIGGER ADDITIONAL SHOWER AND TSTM ACTIVITY OVER THE EASTERN GULF PORTION. MOISTURE FROM THE CARIBBEAN IS FORECAST TO GET CAUGHT UP IN SW FLOW AHEAD OF THE UPPER TROUGH AND MOVE INTO THE SE GULF TONIGHT...AND ACROSS THE SW GULF THU AND THU NIGHT ENHANCING SHOWER AND TSTM ACTIVITY THERE. GLOBAL MODELS ARE DEPICTING WEAK LOW PRES THAT LIFTS NNE OVER THE WESTERN GULF TOWARDS THE GENERAL AREA OF THE N CENTRAL PORTION DURING THE PERIOD OF SAT THROUGH SUN NIGHT. THE MODELS DIFFER WITH EXACT LOCATION. IT APPEARS THAT THIS FEATURE WILL DEVELOP ALONG THE REMNANT TROUGH LEFTOVER FROM THE CURRENT STATIONARY FRONTAL BOUNDARY AS IT WILL BE ENERGIZED BY A RATHER SHARP MID/UPPER LEVEL TROUGH THAT MOVES OFF THE TEXAS COAST...AND OVER THE WESTERN GULF DURING THE WEEKEND. WIND AND SEA FORECAST IN THE NDFD GRIDS WILL BE ADJUSTED ACCORDINGLY. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. FOR WAVE HEIGHTS USED NWPS WAVE PARAMETERS. HIGH CONFIDENCE. RELATIVELY QUIET CONDITIONS CONTINUE OVER THE CARIBBEAN AND TROPICAL N ATLC WATERS PER LATEST SHIP AND BUOY DATA ALONG WITH PARTIAL ASCAT DATA FROM LAST NIGHT AS THE SUBTROPICAL RIDGE N OF THE BASIN REMAINS RATHER WEAK. BASED ON LATEST MODEL DATA THESE CONDITIONS ARE EXPECTED TO CHANGE VERY LITTLE THROUGH MOST OF THE PERIOD...WITH THE EXCEPTION OF THE LATTER PERIODS IN THE S CENTRAL PORTION OF THE SEA. ELY WINDS WILL REMAIN IN THE GENTLE TO MODERATE CATEGORY...AND SEAS AT RATHER LOW LEVELS THROUGH THE PERIOD...EXCEPT IN THE S CENTRAL PORTION DURING LATE SAT AND INTO SUN AT WHICH TIME E-SE TRADES ARE EXPECTED TO INCREASE TO 20 KT UNDER TIGHTENING PRES GRADIENT BEHIND A TROPICAL WAVE DESCRIBED BELOW. THE 06 UTC SURFACE ANALYSIS HAS A TROPICAL WAVE OVER THE CENTRAL CARIBBEAN EXTENDING FROM HAITI TO NE COLOMBIA...MOVING W AT 15 KT. ANOTHER WAVE IS E OF THE TROPICAL N ATLC WATERS ALONG 52W...MOVING W AT 15-20 KT. DEEP LAYER MOISTURE PRODUCING SCATTERED SHOWERS AND TSTMS IS PRESENT ACROSS THE AREA WITH INSTABILITY RELATED TO THE TROPICAL WAVES HELPING TO FURTHER ENHANCE THE ACTIVITY. THE TROPICAL WAVE OVER THE CENTRAL CARIBBEAN WILL MOVE ACROSS THE REST OF THE CENTRAL CARIBBEAN THROUGH WED NIGHT...AND ACROSS THE WESTERN CARIBBEAN THU THROUGH FRI NIGHT. THE TROPICAL WAVE E OF THE FORECAST WATERS NEAR 52W IS EXPECTED TO ENTER THE EASTERN TROPICAL WATERS THIS AFTERNOON...AND MOVE ACROSS THE REST OF THOSE WATERS THROUGH THU...THEN THE EASTERN CARIBBEAN THU NIGHT AND FRI...THE CENTRAL CARIBBEAN FRI NIGHT AND SAT AND THE WESTERN CARIBBEAN SEA SAT NIGHT THROUGH SUN NIGHT. GUSTY WINDS ARE POSSIBLE WITH SHOWER AND TSTM ACTIVITY...ESPECIALLY THE ACTIVITY ASSOCIATED WITH THE WAVES. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL. MWW3/NWPS BLEND USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. THE 06 UTC SURFACE ANALYSIS HAS A STATIONARY FRONT OVER THE FAR NW CORNER OF THE BASIN. A RELATIVELY WEAK RIDGE EXTENDS FROM NEAR BERMUDA SW TO THE NW BAHAMAS. PARTIAL ASCAT DATA PASS FROM 0218 UTC LAST NIGHT SHOWED GENTLE E-SE WINDS ACROSS THE AREA. THE THE BUOYS ARE ALSO REPORTING SIMILAR E-SE WINDS. BUOY AND SHIP OBSERVATIONS ALONG WITH RECENT ALTIMETER PASSES SHOW SEAS IN THE 4-6 FT RANGE E OF THE BAHAMAS AND 1-2 FT SEAS W OF THE BAHAMAS. HIGHER SEAS OF 5-7 FT ARE NW OF THE STATIONARY FRONT WHERE A TIGHT PRES GRADIENT EXISTS. THE STATIONARY FRONT JUST NW OF THE BASIN WILL WEAKEN INTO A COAST BY FRI. THE PRES GRADIENT BETWEEN THE FRONT AND STRONG HIGH PRES TO ITS NW WILL MAITAIN A TIGHT PRES GRADIENT OVER THE FAR NW WATERS...WHICH SHOULD SUPPORT MODERATE NE TO E WINDS THERE THROUGH FRI. THEREAFTER...THE GRADIENT SLACKENS ALLOWING FOR THESE WINDS TO DIMINISH TO THE GENTLE RANGE. THE 5-7 FT SEAS INDUCED BY THESE WINDS WILL SUBSIDE TO 4-5 FT FRI...AND CHANGE LITTLE THROUGH SUN. THE NORTHERN PORTION OF THE CENTRAL CARIBBEAN TROPICAL WAVE WILL MOVES ACROSS THE BAHAMAS THROUGH EARLY THU...AND APPROACH S FLORIDA LATER DURING THU. ABUNDANT MOISTURE ASSOCIATED WITH THIS WAVE WILL RESULT IN ADDITIONAL SCATTERED TO NUMEROUS SHOWERS AND TSTMS TO EXITS OVER MUCH OF THE WESTERN PORTION THROUGH FRI. GUSTY WINDS AND LIGHTNING STRIKES CAN BE EXPECTED WITH THIS ACTIVITY. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 AGUIRRE. NATIONAL HURRICANE CENTER.