000 AGXX40 KNHC 311020 AAA MIMATS MARINE WEATHER DISCUSSION...UPDATED NWS NATIONAL HURRICANE CENTER MIAMI FL 520 AM EDT THU OCT 31 2013 UPDATED GULF OF MEXICO SECTION 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...UPDATED FOR WINDS MODEL PREFERENCE: LATEST GFS BLENDED WITH OFFICIAL FORECAST. MWW3 USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. HIGH PRES RIDGING IS PRESENT OVER THE MAJORITY OF THE AREA WHILE DEEPENING LOW PRES IS W OF THE AREA OVER THE CENTRAL PLAINS. THE FLOW ACROSS THE GULF IS CONTROLLED BY THE RIDGE...AND IS PREDOMINATELY SELY IN DIRECTION...EXCEPT FOR MAINLY SLY IN THE FAR WESTERN PORTION. AS FOR WIND SPEEDS THE LATEST AND CURRENT OBSERVATIONS FROM THE BUOYS AND OIL RIG PLATFORMS CURRENTLY SHOW SE WINDS OF 15-20 KT OVER MUCH OF THE GULF ZONES. THE EXCEPTIONS ARE IN THE NW AND THE WESTERN PART OF THE N CENTRAL PORTIONS WHERE SE-S WINDS OF 20-25 KT ARE OCCURRING...AND IN THE NE PORTION WHERE LIGHTER WINDS OF 10-15 KT ARE BEING REPORTED. THE 0344 ASCAT PASS REVEALED A SOLID SWATH OF SE 20 KT WINDS IN NW PORTION...AND A SMALL POCKET OF 15-20 KT WINDS NEAR THE NORTHERN YUCATAN PENINSULA. THE OBSERVATIONS SHOW SEAS OF 5-6 FT OVER MUCH OF THE CENTRAL AND WESTERN GULF ZONES...EXCEPT FOR HIGHER SEAS OF 7-8 FT FROM 25N TO 28N W OF 92W. LOWER SEAS OF 2-3 FT ARE IN THE NE PORTION WHERE THE LIGHTER FLOW EXISTS. SEAS OF UP TO 7 FT ARE IN THE STRAITS OF FLORIDA WHERE PERSISTENT NE 20 KT FLOW IS EVIDENT. THE RIDGING ACROSS THE AREA WILL CONTINUE TO SLIDE EASTWARD THROUGH FRI ALLOWING FOR THE NEXT COLD FRONT...ASSOCIATED WITH THE PLAINS LOW PRES...TO MOVE OFF THE TEXAS COAST THIS EVENING. THE FRONT WILL REACH FROM NEAR SE LOUISIANA TO SE TEXAS EARLY ON FRI...THEN SLOW DOWN SOME AS IT REACHES FROM THE FLORIDA BIG BEND TO NEAR 25N91W AND STATIONARY TO NEAR TAMPICO MEXICO BY LATE FRI NIGHT. WEAK HIGH PRES WILL BUILD EASTWARD ACROSS THE GULF IN ITS WAKE. BY SAT MORNING...THE WEAK HIGH PRES IS REPLACED BY STRONGER HIGHER PRES THAT WILL ACT TO PUSH THE FRONT TO THE SE AGAIN. THE FRONT WILL THEN REACH FROM NEAR FORT MYERS FLORIDA TO NEAR 24N90W AND TO INLAND MEXICO NEAR TAMPICO BY SAT AFTERNOON...AND TO THE FAR SE GULF AND STRAITS OF FLORIDA BY SAT EVENING. BY LATE SAT NIGHT...THE FRONT SHOULD HAVE PUSHED FARTHER SE TO JUST SE OF THE AREA. N-NE WINDS OF 10-15 KT WILL INITIALLY FOLLOW THE FRONT THROUGH MOST OF FRI...THEN INCREASE TO 20-25 KT SAT AS A TIGHTER PRES GRADIENT DEVELOPS W OF THE FRONT UNDER THE STRONGER HIGHER PRES THAT BUILDS EASTWARD OVER THE AREA. THE HIGH PRES THEN WEAKENS SUN AND MON AS IT QUICKLY ALSO 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 NE-E 15-20 KT WINDS THERE. EXPECT SEAS TO CONTINUE UP TO 8 FT IN THE WESTERN GULF THROUGH SAT BEFORE SUBSIDING TO 4-5 FT SUN...AND TO 3-4 FT MON. WINDS AND SEAS ARE EXPECTED TO BE HIGHER IN SCATTERED TO NUMEROUS SHOWERS AND POSSIBLE STRONG TSTMS ALONG AND AHEAD OF THE COLD 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 0200 UTC DEPICTED NE-E WINDS OF 15-20 KT OVER MUCH OF THE CENTRAL PORTION OF THE CARIBBEAN SEA S OF 16N... WITH A SMALL SWATH OF NE 20-25 KT WINDS WITHIN 120 NM OF THE COLOMBIAN COAST. LIGHTER E WINDS OF 10-15 KT ARE NOTED N OF 16N...AND ELSEWHERE ACROSS THE CARIBBEAN SEA AND TROPICAL N ATLC. THE EXCEPTION IS IN THE NW PORTION N OF 19N WHERE THE WESTERN FRINGE OF THE ASCAT PASS INDICATED NE 20-25 KT WINDS THERE. CURRENT BUOYS REPORTS SHOW SEAS OF 4-6 FT IN THE MAJORITY OF THE CARIBBEAN ZONES...WITH HIGHER SEAS OF UP TO AROUND 8 FT POSSIBLE NEAR THE COAST OF COLOMBIA AS INFERRED FROM A SHIP OBSERVATION IN THAT VICINITY. A TROPICAL WAVE MOVING W 10-15 KT IS OVER THE WESTERN CARIBBEAN SEA WITH ITS AXIS FROM NEAR 19N79W TO 10N80W. NO ACTIVE WEATHER IS ASSOCIATED WITH THIS WAVE. THE WAVE WILL MOVE INLAND CENTRAL AMERICA AND THE YUCATAN PENINSULA FRI. A SURFACE TROUGH IS JUST MOVING ACROSS THE LESSER ANTILLES...WHILE ANOTHER ONE IS ANALYZED TO ITS SE FROM 11N50W TO 06N52W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE PRESENT BETWEEN 57W-67W. MODEL GUIDANCE ARE CONSISTENT IN PICKING UP THE NE TO SE WIND SHIFT WITH THERE FEATURES. THE FIRST TROUGH WILL TRANSLATE WESTWARD AS A TROPICAL WAVE FEATURE LATER TODAY AS IT MOVES ACROSS THE EASTERN CARIBBEAN ...THEN ACROSS THE CENTRAL CARIBBEAN TONIGHT THROUGH SAT. PRESENTLY...INDICATIONS ARE THAT THIS WAVE WILL SLOW DOWN DURING SAT OVER THE CENTRAL CARIBBEAN...AND TRANSITION BACK TO A TROUGH. THE TROUGH WILL PERSIST INTO MON AS PERHAPS A BROAD TROUGH WITH WEAK LOW PRES FORMING ON IT. THE MAIN IMPACT TO THE FORECAST WATERS FROM THIS FEATURE WILL MOST LIKELY BE FROM SHOWER AND TSTM ACTIVITY THAT COULD LIKELY PRODUCE HIGHER WINDS AND SEAS. THE NE 20 KT WINDS IN THE NW PORTION OF THE CARIBBEAN WILL CONTINUE THROUGH AT LEAST EARLY THIS AFTERNOON 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 WEAKENING STATIONARY FRONT OVER THE FAR SE PORTION OF THE BASIN FROM 23N65W TO NEAR THE MONA PASSAGE. HIGH PRES COVERS THE REST OF THE BASIN. THE 0202 UTC ASCAT PASS SHOWED A SWATH OF NE 15-20 KT WINDS IN THE SW AND NE PORTIONS...AND LIGHTER E WINDS OF 10-15 KT ELSEWHERE OVER THE WESTERN AND EASTERN PORTIONS. NE 15-20 KT ARE BEING REPORTED BY A COUPLE OF SHIPS JUST E AND SE OF THE BAHAMAS. BUOY AND SHIP REPORTS NOTE SEAS IN THE 4-5 FT RANGE EXCEPT FOR UP TO 6-7 FT IN THE FAR SW PORTION AND STRAITS OF FLORIDA...AND LOWER SEAS OF 2-4 FT IN THE FAR NW PORTION. THE AFOREMENTIONED HIGH PRES OVER THE AREA WILL SHIFT EASTWARD THROUGH SAT WHILE WEAKENING. THIS WILL ALLOW FOR A COLD FRONT TO MOVE INTO THE FAR NW PORTION OF THE BASIN LATE FRI NIGHT AND INTO EARLY SAT MORNING. THE COLD FRONT IS FORECAST TO REACH FROM NEAR 31N75W TO SE FLORIDA BY SAT EVENING...FROM NEAR 31N65W TO VICINITY EASTERN CUBA SUN EVENING...AND MOVE TO E OF THE ZONES MON. 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 IN DIRECTION ON SUN AS THE EASTERN PERIPHERY OF CONTINENTAL HIGH PRES PRESSES EASTWARD TO THE FAR WESTERN PORTION OF THE SW N ATLC. THIS AREA OF HIGH PRES WILL THEN BE SUBSTANTIALLY REINFORCED BY STRONGER HIGH PRES FROM THE N LATE SUN INTO MON LEADING TO A SIGNIFICANT TIGHTENING OF THE PRES GRADIENT BETWEEN IT AND THE FRONT OVER THE EASTERN PORTION. THIS WILL LEAD TO NE WINDS INCREASING TO 20-25 KT OVER MUCH OF THE BASIN SUN AND MON WITH SEAS IN THE 6-9 FT RANGE...AND WITH POSSIBLE SEAS OF 8-10 FT E OF THE NW BAHAMAS...AND OVER THE FAR NORTHERN PORTION. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... GMZ011...NONE. GMZ013...NONE. GMZ015...NONE. GMZ017...NONE. GMZ019...NONE. GMZ021...NONE. GMZ023...NONE. GMZ025...NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... AMZ011...NONE. AMZ013...NONE. AMZ015...NONE. AMZ017...NONE. AMZ019...NONE. AMZ021...NONE. AMZ023...NONE. AMZ025...NONE. AMZ027...NONE. AMZ029...NONE. AMZ031...NONE. AMZ033...NONE. AMZ035...NONE. AMZ037...NONE. AMZ039...NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... AMZ111...NONE. AMZ113...NONE. AMZ115...NONE. AMZ117...NONE. AMZ119...NONE. AMZ121...NONE. AMZ123...NONE. AMZ125...NONE. AMZ127...NONE. *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER AGUIRRE. NATIONAL HURRICANE CENTER.