000 AGXX40 KNHC 300838 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 400 AM EDT WED OCT 30 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: LATEST GFS BLENDED WITH OFFICIAL FORECAST. MWW3 USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. HIGH PRES CENTERED OVER NORTHERN GEORGIA EXTENDS A RIDGE SW ACROSS THE NORTHERN GULF. THE ASSOCIATED ANTICYCLONIC FLOW IS PRESENT ACROSS THE AREA PROVIDING FOR MAINLY MODERATE E-SE FLOW THROUGHOUT...EXCEPT FOR FRESH NE FLOW ACROSS THE SE PORTION AND STRAITS OF FLORIDA AS WAS NOTED IN THE 0224 ASCAT PASS...AND IS CURRENTLY BEING REPORTED BY A COUPLE OF SHIPS IN THAT PART OF THE GULF. THE BUOY OBSERVATIONS ALONG WITH A FEW SHIP OBSERVATIONS ARE INDICATING HIGHER SEAS IN MOST ZONES THAN NOTED THE PAST FEW DAYS. SEAS ARE IN THE RANGE OF 5-7 FT...WITH THE EXCEPTIONS OF HIGHER SEAS OF 6-8 FT IN THE FAR SE PART AND STRAITS OF FLORIDA...AND LOWER SEAS OF 2-4 FT IN THE NE PART. GLOBAL MODELS AGREE THAT THE HIGH PRES WILL SHIFT EASTWARD THROUGH THU NIGHT ALLOWING FOR THE GRADIENT IN THE FAR SE GULF TO SLACKEN. WITH THE HIGH SHIFTING EASTWARD...THIS WILL ALSO ALLOW FOR A WEAK COLD FRONT TO MOVE OFF THE TEXAS COAST THU EVENING. THE FRONT WILL REACH FROM NEAR SE LOUISIANA TO SE TEXAS EARLY ON FRI...FROM THE WESTERN FLORIDA TO THE WESTERN GULF BY LATE FRI...FROM NEAR FORT MYERS FLORIDA TO NEAR 24N92W AND TO INLAND MEXICO NEAR TAMPICO BY SAT AFTERNOON...AND TO THE FAR SE GULF AND STRAITS OF FLORIDA BY EARLY SUN. N-NE WINDS OF 10-15 KT WILL INITIALLY FOLLOW THE FRONT THROUGH FRI...THEN INCREASE ON SAT TO 20 KT...AND POSSIBLY TO 20-25 KT IN THE W CENTRAL GULF ZONE AS HIGH PRES BEHIND THE FRONT IS REINFORCED BY A STRONGER SURGE OF HIGH PRES THAT BUILDS SOUTHEASTWARD ACROSS THE AREA. THE HIGH PRES THEN WEAKENS SUN AS IT SLIDES EASTWARD ALLOWING FOR THE WINDS TO DIMINISH 10-15 KT OVER THE MAJORITY OF THE ZONES...EXCEPT FOR A LINGERING TIGHT GRADIENT IN THE EASTERN HALF OF THE GULF ALLOWING FOR N-NE 15-20 KT WINDS THERE. EXPECT SEAS TO BE IN THE RANGE OF 5-7 FT IN THE WESTERN GULF SAT BEFORE SUBSIDING TO 4-5 FT SUN. WIND AND SEAS ARE EXPECTED TO BUILD IN SCATTERED TO NUMEROUS SHOWERS AND TSTMS ALONG AND AHEAD OF THE FRONT. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 65W... MODEL PREFERENCE: LATEST GFS BLENDED WITH OFFICIAL FORECAST. MWW3 USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. AN ASCAT PASS FROM 0222 UTC DEPICTED NE-E WINDS OF 15-20 KT OVER MUCH OF THE CENTRAL AND EASTERN PORTIONS OF THE CARIBBEAN SEA. IT SUGGESTED THAT LIGHTER WINDS OF 10-15 KT WERE OVER THE WESTERN PORTION OF THE SEA. AN ASCAT PASS FROM 0040 UTC SHOWED NE-E WINDS OF 10-15 KT OVER THE NORTHERN AND CENTRAL SECTIONS OF THE TROPICAL N ATLC AS A TROUGH FEATURE THERE APPROACHES THE LESSER ANTILLES. BUOYS ARE REPORTING SEAS OF 5-7 FT OVER MUCH OF THE TROPICAL N ATLC AS WELL AS OVER MUCH OF THE CENTRAL AND EASTERN CARIBBEAN PORTIONS S OF 16N. SEAS ARE LOWER...IN THE 3-4 FT RANGE...OVER THE WESTERN CARIBBEAN WITH A FEW POCKETS OF 4-6 FT SEAS. A TROPICAL WAVE MOVING NEAR 15 KT IS ANALYZED ROUGHLY ALONG A POSITION FROM 19N73W TO 11N74W. THE WAVE DOESN'T APPEAR AS ROBUST AS IT DID THE LAST FEW DAYS NOW THAT IT IS MOVING TO THE W OF THE DEEP UPPER TROUGH SITUATED TO ITS N. SCATTERED SHOWERS AND ISOLATED TSTMS ARE PRESENT FROM 12N TO 16N BETWEEN 68W-73W. MODEL GUIDANCE FIELDS SUGGESTS THAT THE WAVE WILL WEAKEN AS MOVES ACROSS THE WESTERN PART OF THE CENTRAL CARIBBEAN TODAY THROUGH THU EVENING. THE NE-E WINDS NOTED IN THE 0040 UTC ASCAT PASS ARE ATTRIBUTED TO A RATHER LARGE TROUGH...BRIEFLY REFERENCED ABOVE...THAT HAS DEVELOPED WITHIN ABOUT 180 NM E OF THE LESSER ANTILLES. THE NE- SE WIND SHIFT WITH THE TROUGH IS HIGHLIGHTED RATHER NICELY IN THE MODELS. THE TROUGH WILL MIGRATE WESTWARD AS A TROPICAL WAVE FEATURE AS IT ENTERS THE FAR EASTERN CARIBBEAN TODAY. IT WILL MOVE ACROSS THE REMAINDER OF THE EASTERN CARIBBEAN THROUGH THU...THEN ACROSS THE CENTRAL PORTION THU NIGHT THROUGH SAT. POTENTIAL VORTICITY GUIDANCE SUGGESTS THAT A PIECE OF THE WAVE HANGS BACK AS A TROUGH OVER THE EASTERN CARIBBEAN THAT GRADUALLY TRANSLATES WESTWARD THROUGH SUN. MODELS...FOR THE MOST PART...INDICATE THAT LOW PRES COULD DEVELOP FROM THIS TROUGH FRI THROUGH SUN. RIGHT NOW BASED ON THE GUIDANCE...IT APPEARS THAT MAIN IMPACT TO THE FORECAST WATERS FROM THIS FEATURE WILL BE SHOWER/TSTM ACTIVITY THAT COULD LIKELY PRODUCE HIGHER WINDS AND SEAS. NE WINDS OF 20 KT ACROSS THE NW CARIBBEAN AS HIGHLIGHTED BY THE 0224 UTC ASCAT PASS WILL LAST INTO EARLY THU AS THE PRES GRADIENT THERE SLACKENS. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH OFFICIAL FORECAST. MWW3 USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. THE 06 UTC PRELIMINARY SURFACE ANALYSIS HAS A COLD FRONT OVER THE FAR SE PORTION OF THE BASIN WITH HIGH PRES BUILDING SOUTHEASTWARD BEHIND IT. THE 0224 UTC ASCAT PASS SHOWED NE WINDS OF 15-20 KT ACROSS MUCH OF THE AREA...EXCEPT FOR LIGHTER NE WINDS OF 10 KT S OF ABOUT 27N AND E OF 73W AND STRAIGHT NE 20 KT WINDS IN THE FAR SW PART AND STRAITS OF FLORIDA. SEAS OVER THE BASIN ARE IN THE 4-5 FT RANGE EXCEPT FOR UP TO 6-8 FT IN THE FAR SW PORTION AND STRAITS OF FLORIDA...AND LOWER SEAS OF 2-4 FT IN THE FAR NW PORTION. THE HIGH PRES OVER THE AREA WILL SHIFT EASTWARD THROUGH FRI AND WEAKEN ALLOWING FOR A COLD FRONT TO MOVE INTO THE FAR NW PORTION LATE FRI NIGHT AND INTO EARLY SAT. THE FRONT IS FORECAST TO REACH FROM NEAR 31N72W TO SE FLORIDA BY SAT EVENING...AND FROM NEAR 31N68W TO VICINITY EASTERN CUBA SUN AFTERNOON. NW WINDS OF 15-20 KT WILL FOLLOW BEHIND THE FRONT WITH SEAS IN THE RANGE OF 5-6 FT RANGE. THE WINDS THEN BECOME MORE FROM THE N BY SUN AS THE EASTERN PERIPHERY OF CONTINENTAL HIGH PRES PRESSES EASTWARD TO THE FAR WESTERN PORTION OF THE SW N ATLC. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... GMZ011...NONE. GMZ013...NONE. GMZ015...NONE. GMZ017...NONE. GMZ019...NONE. GMZ021...NONE. GMZ023...NONE. GMZ025...NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... AMZ011...NONE. AMZ013...NONE. AMZ015...NONE. AMZ017...NONE. AMZ019...NONE. AMZ021...NONE. AMZ023...NONE. AMZ025...NONE. AMZ027...NONE. AMZ029...NONE. AMZ031...NONE. AMZ033...NONE. AMZ035...NONE. AMZ037...NONE. AMZ039...NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... AMZ111...NONE. AMZ113...NONE. AMZ115...NONE. AMZ117...NONE. AMZ119...NONE. AMZ121...NONE. AMZ123...NONE. AMZ125...NONE. AMZ127...NONE. *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER AGUIRRE. NATIONAL HURRICANE CENTER.