000 AGXX40 KNHC 041952 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 250 PM EDT SUN NOV 04 2012 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLC...AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... LATEST SURFACE ANALYSES FROM EARLY THIS AFTERNOON HAS A 1020 MB HIGH CENTER AT 27N88W...WHILE A TROUGH IS JUST INLAND CENTRAL TEXAS. LATEST BUOY...OIL RIG PLATFORMS AND THE ASCAT PASS FROM 1540 UTC NOTED RELATIVELY LIGHT WINDS AND LOW SEAS THROUGHOUT WITH S-SW WINDS OF 5 KT OR LESS IN THE NE PORTION AS WELL AS NEAR AND AROUND THE IMMEDIATE VICINITY OF THE HIGH. SE-S WINDS OF 10 KT ARE OVER THE WESTERN PART OF THE GULF...AND E-SE 10-15 KT WINDS IN THE SW PORTION. THE LATEST OBSERVATIONS CONTINUE TO SHOW SEAS IN THE LOW RANGE OF 2-3 FT W OF 90W...AND 1-2 FT E OF 90W. THE 1020 MB IS FORECAST TO NE EARLY TO JUST E OF N FLORIDA TONIGHT ALLOWING FOR A WEAK COLD FRONT TO QUICKLY PUSH SE ACROSS THE EASTERN PORTION OF THE GULF. THE FRONT WILL BE FOLLOWED SHIFTING WINDS THE N AT 10-15 KT WITH SEAS ONLY BRIEFLY BUILDING SLIGHTLY BEFORE SUBSIDING MON. THE GLOBAL MODELS HAVE BACKED DOWN ON THE STRENGTH OF THE WINDS BEHIND THIS FRONT AS PREVIOUSLY ADVERTISED...HOWEVER THE MODELS...WITH THE EXCEPTION OF THE UKMET...DO CONTINUE TO SUGGEST THAT LOW PRES WILL FORM ALONG OR JUST OFFSHORE THE WESTERN FLORIDA PANHANDLE MON EVENING WITH THE DETERMINISTIC GFS NOW MORE ON THE SOUTHERN LEG OF THE OVERALL SUITE OF THE GUIDANCE. THIS SOLN SEEMS MORE PLAUSIBLE WITH BOTH NORTHERN AND SOUTHERN JET STREAM BRANCHES COMING INTO PHASE OVER THE NORTHERN GULF WATERS TONIGHT THROUGH MON NIGHT WITH SEVERAL IMPULSES RIDING ALONG IT EVEN FROM THE FAR EASTERN PACIFIC. THE LOW WILL PUSH ANOTHER COLD FRONT...WHICH WILL BE STRONGER THAN THE ONE EXPECTED TONIGHT...ACROSS THE GULF LATE MON NIGHT INTO TUE. THIS FRONT WILL BE FOLLOWED NW-N WINDS INCREASING TO 15-20 KT PRIMARILY OVER THE EASTERN AND CENTRAL PORTIONS OF THE GULF WITH SEAS BUILDING TO AROUND 6 OR 7 FT. WINDS AND SEAS THEN QUICKLY DIMINISH WED THROUGH FRI AS WEAK HIGH PRES SETTLES IN OVER THE AREA. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... SATELLITE IMAGERY FROM DURING THE DAY HAVE REVEAL AND PRESENTLY REVEAL THAT THE AREA OF MULTILAYERED CLOUDS WITH SCATTERED TO NUMEROUS TSTMS NOTED THE PAST FEW DAYS IN THE SW CARIBBEAN SEA IN ASSOCIATION WITH A SURFACE TROUGH HAS SIGNIFICANTLY DISSIPATED. THE TROUGH HAS MOVED JUST INLAND THE COAST OF COSTA RICA AND PANAMA. BOTH BUOY OBSERVATIONS ALONG WITH ASCAT PASSES FROM 1400 UTC AND 1542 THIS MORNING REVEALED RELATIVELY LIGHT NE-E TRADE WINDS THROUGHOUT. A TIGHTER PRES GRADIENT NEAR THE COAST OF COLOMBIA IS ALLOWING FOR NE-E WINDS OF 20-25 KT THERE...BUT SHOULD DIMINISH TO 15-20 KT BY MON NIGHT AS THE GRADIENT SLACKENS. SEAS TO 8 FT ARE POSSIBLE THERE...BUT ARE ALSO EXPECTED TO LOWER MON NIGHT. SEAS OF 6-7 FT IN A N SWELL ARE STILL EVIDENT OVER THE NORTHERN PORTION OF THE TROPICAL N ATLC...AND ARE EXPECTED TO BE REPLENISH BY ANOTHER BATCH OF N-NE SWELLS FROM THE NE AND EASTERN ATLC DURING THE UPCOMING WEEK BRINGING MAX SEAS OF 6-8 FT THERE. PATCHES OF MOISTURE IN THE ELY TRADE WIND FLOW ARE RESULTING IN ISOLATED SHOWERS ACROSS MUCH OF THE CENTRAL AND EASTERN PORTIONS OF THE CARIBBEAN...AND OVER THE NORTHERN AND CENTRAL TROPICAL N ATLC. SCATTERED SHOWERS AND ISOLATED TSTMS ARE PRESENT OVER THE SOUTHERN SECTION OF THE TROPICAL N ATLC. FOR THIS FORECAST PACKAGE ONLY SMALL TWEAKS WILL BE MADE WITH RESPECT TO THE PREVIOUS MORNING UPDATE PACKAGE IN THE NEXT TERM. A COLD FRONT IS STILL FORECAST TO MOVE INTO THE YUCATAN PENINSULA AND WESTERN CUBA LOCATIONS TUE NIGHT...THEN BEGIN WEAKEN AS IT REACHES FROM VICINITY WINDWARD PASSAGE TO NEAR NORTHERN HONDURAS WED EVENING...AND CONTINUE FURTHER AS IT REACHES FROM THE DOMINICAN REPUBLIC TO NEAR NE NICARAGUA BY FRI. NLY WINDS OF 10-15 KT BEHIND THE FRONT ARE EXPECTED TO INCREASE TO 15-20 KT OVER PORTIONS OF THE WESTERN CARIBBEAN WED...AND ALSO FILTER SWD ALONG THE COAST OF NICARAGUA INTO THU. THE NLY WINDS THEN DIMINISH TO 10-15 KT WHILE VEERING TO THE NE LATE THU AND FRI. SEAS BEHIND THE FRONT SHOULD BE IN THE 4-6 FT RANGE. SOUTHWEST NORTH ATLC S OF 31N W OF 55W... THE 18 UTC PRELIMINARY SURFACE ANALYSIS HAS A WEAKENING COLD FRONT EXTENDING FROM 31N61W SW TO NEAR 25N73W...WHILE A DISSIPATING OLD FRONTAL TROUGH IS OVER THE FAR SE WATERS FROM NEAR 21N65W SW TO JUST N OF HISPANIOLA. SCATTERED SHOWERS AND ISOLATED TSTMS ARE WITHIN 180 NM EITHER SIDE OF THE FRONTAL TROUGH. A WEAK 1019 MB HIGH IS CENTERED NEAR 29N73W. LATEST ASCAT AND BUOY DATA SHOW THAT THE FRESH TO STRONG W-NW WINDS OBSERVED OVER THE NORTHERN PART OF THE AREA E OF 73W HAVE DIMINISHED. SEAS THERE HAVE LOWERED TO 8 FT IN A NW SWELL. LIGHT NE-E WINDS ARE ELSEWHERE ACROSS THE BASIN. SEAS ELSEWHERE ARE 4-5 FT...EXCEPT 2-3 FT W AND NW OF THE BAHAMAS. FOR THIS FORECAST...WILL FOLLOW DETERMINISTIC GFS GUIDANCE FOR THE BASIN IN RELATION TO FRONTAL POSITIONS AND ASSOCIATED WINDS AND SEAS...EXCEPT WILL INCORPORATE A BLEND OF THE GFS/ECMWF/UKMET FOR WINDS IN THE NORTHERN PORTION OF THE AREA W OF 70W THROUGH WED NIGHT. THE WEAKENING COLD FRONT WILL MOVE E OF THE ZONES TONIGHT...AND THE 1018 MB HIGH WILL DISSIPATE BY MON AFTERNOON. THIS WILL ALLOW FOR DEVELOPING LOW PRES...SUPPORTED BY A VERY AMPLIFIED UPPER LEVEL SHORTWAVE TROUGH...TO MOVE ENE FROM THE N CENTRAL GULF AND TRACK NE OFF THE MID-ATLC THROUGH MON NIGHT THROUGH WED. THIS LOW WILL DRAG A STRONG COLD FRONT INTO THE NW WATER TUE NIGHT AND WED FOLLOWED BY INCREASING NW-N WINDS OF 20-25 KT WITH POSSIBLE GUSTS TO 30 KT N OF 29N PER ECMWF/GFS/NOGAPS/UKMET GUIDANCE. SEAS OVER THAT PORTION OF THE BASIN ARE EXPECTED TO BUILD TO 9-12 FT WITH HIGHER MAXED ALONG AND JUST N OF THE AREA BOUNDARY AS ADVERTISED BY THE NOAA WWWIII...UKMET AND ECMWF WAVEWATCH GUIDANCES. THE FRONT WILL BE PRECEDED BY INCREASING SLY WINDS...AND IS EXPECTED TO REACH A POSITION FROM NEAR 31N76W TO CENTRAL CUBA BY EARLY WED...FROM NEAR 31N67W TO WINDWARD PASSAGE WED EVENING...AND BEGIN TO WEAKEN AS IT REACHES FROM NEAR 27N65W TO DOMINICAN REPUBLIC THU. THE FRONT WILL THEN DISSIPATE OVER THE FAR SE WATERS FRI. HIGH PRES BUILDS SE ACROSS THE BASIN BEHIND THE FRONT. WINDS BEHIND THE FRONT BECOME RATHER LIGHT NLY THU AND FRI...EXCEPT OVER THE FAR NORTHERN WATERS THU WHERE A LINGERING TIGHT PRES GRADIENT SHOULD ALLOW FOR FRESH W TO NW WINDS AND SEAS UP TO POSSIBLY 10 OR 11 FT. HOWEVER...THESE WINDS AND SEAS ALSO SUBSIDE FRI. NOTE...GRIDDED MARINE FORECAST IS AVAILABLE AT WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE GULF OF MEXICO... .NONE. CARIBBEAN SEA AND TROPICAL N ATLC... .NONE. SW N ATLANTIC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ FORECASTER AGUIRRE