000 AGXX40 KNHC 161823 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 123 PM EST WED DEC 16 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: GLOBAL MODEL CONSENSUS. LATEST TAFB-NWPS USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. A WARM FRONT HAS LIFTED JUST N OF THE N CENTRAL AND NE GULF WATERS WHILE A COLD FRONT HAS MOVED JUST OFFSHORE OF THE TEXAS COAST. A LINE OF CONVECTION WITH FREQUENT LIGHTNING IS EVIDENT JUST AHEAD OF THE FRONT...BUT SO FAR THE ACTIVITY HAS REMAINED OVER INLAND PORTIONS. OFFSHORE PLATFORM OBSERVATIONS HAVE BEEN REPORTING FOG IN THE NW AND N CENTRAL GULF AHEAD OF THE FRONT WHICH MAY OCCASIONALLY REDUCE VISIBILITIES. OTHERWISE BROAD HIGH PRES RIDGING DOMINATES THE BASIN WITH MAINLY MODERATE RETURN FLOW AND 2-4 FT SEAS. BEHIND THE FRONT...ELEVATED PLATFORMS ARE ALREADY REPORTING WINDS UP TO 30 KT...MORE LIKELY 20-25 KT AT 10-M DOWN TO THE SURFACE. THE FRONT IS FORECAST TO REACH FROM S CENTRAL LOUISIANA TO NEAR TAMPICO MEXICO THIS EVENING THEN FROM NEAR MOBILE ALABAMA TO VERACRUZ MEXICO THU MORNING THEN FROM NEAR TAMPA BAY FLORIDA TO THE SW GULF NEAR 18N93W FRI MORNING PUSHING SE OF THE BASIN FRI EVENING. FRESH TO STRONG NORTHERLY FLOW WILL SPREAD ACROSS THE BASIN IN THE WAKE OF THE FRONT...BUT WINDS WILL BE EVEN STRONGER OFFSHORE OF VERACRUZ WHERE A GALE WARNING IS NOW IN EFFECT THU NIGHT THROUGH FRI. SREF GUIDANCE CONTINUES TO TREND UPWARDS WITH REGARD TO 34-KT PROBABILITIES...NOW NEAR 75 PERCENT...WHILE ODDLY THE GEFS 34-KT PROBABILITIES REMAIN AT 0 PERCENT. GLOBAL MODEL GUIDANCE IS IN QUITE GOOD AGREEMENT REGARDING THE MOVEMENT AND PLACEMENT OF THE FRONT. SEAS ARE FORECAST TO BUILD TO UP TO 10-14 FT AS FORECAST BY THE LATEST AND GREATEST RUN OF THE IN- HOUSE TAFB-NWPS WAVE MODEL. WINDS WILL DIMINISH ACROSS THE NW HALF OF THE BASIN AS HIGH PRES BUILDS IN ACROSS THE SOUTHERN MISSISSIPPI VALLEY FRI NIGHT THROUGH SAT...WITH THE HIGH SLIDING TO THE CAROLINAS BY SAT NIGHT INTO EARLY SUN WHICH WILL ALLOW FOR WINDS TO TURN TO THE E-SE BASIN- WIDE BY SUN MORNING. MODEL GUIDANCE INDICATES THE POSSIBILITY OF A VERY WEAK FRONT DROPPING INTO THE FAR NW PART OF THE BASIN ON MON BUT THE RIDGING APPEARS TO BE TOO STRONG TO ALLOW FOR MUCH FORWARD PROGRESS WITH THE BOUNDARY BEING PUSHED BACK INLAND OVER TEXAS BY LATE MON. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: GLOBAL MODEL CONSENSUS. LATEST TAFB-NWPS USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. DIFFLUENCE ALOFT E OF AN UPPER TROUGH NEAR 72W CONTINUES TO SUPPORT A SOLID AREA OF SCATTERED SHOWERS AND TSTMS WITH FREQUENT LIGHTNING AS NOTED IN THE LIGHTNING DENSITY DISPLAY. THIS ACTIVITY IS FOUND FROM 12.5N TO 18N BETWEEN 69W AND 73W AND IS GRADUALLY SHIFTING EASTWARD. A 1018 MB HIGH CENTER IS LOCATED N OF THE AREA IN THE ATLC NEAR 23N52W WHILE 1006 MB LOW PRES IS LOCATED OVER NW VENEZUELA NEAR 08N72W. THE PRES GRADIENT BETWEEN THESE TWO FEATURES CONTINUES TO SUPPORT FRESH TO LOCALLY STRONG TRADES IN THE CENTRAL CARIBBEAN AND RESULTANT 5-7 FT SEAS. OTHERWISE...MAINLY MODERATE TO LOCALLY FRESH E-SE FLOW PREVAILS ALONG WITH 3-5 FT SEAS. THESE CONDITIONS ARE FORECAST TO PERSIST THROUGH TODAY. RATHER SIGNIFICANT CHANGES ARE FORECAST AFTERWARDS AS STRONG HIGH PRES WILL BUILD SE OVER THE CENTRAL ATLC TONIGHT INTO THU WHICH WILL STRENGTHEN THE PRES GRADIENT ALLOWING FOR THE FRESH TO STRONG TRADES TO EXPAND AND SPREAD WESTWARD THROUGH THE END OF THE WEEK AND THE UPCOMING WEEKEND. A STRONG COLD FRONT IS FORECAST TO SLIP SE OF THE YUCATAN CHANNEL FRI NIGHT WITH FRESH TO STRONG N-NE WINDS FOLLOWING THE FRONT WHICH WILL QUICKLY BUILD SEAS TO UP TO AROUND 11 FT NEAR THE CHANNEL LATE FRI NIGHT INTO SAT MORNING. THE FRONT WILL REACH FROM CENTRAL CUBA TO NW HONDURAS SAT MORNING THEN FROM EASTERN CUBA TO EASTERN HONDURAS SAT EVENING WHERE IT WILL BECOME STATIONARY AND GRADUALLY BECOME DIFFUSE THROUGH SUN. GLOBAL MODEL GUIDANCE IS IN QUITE GOOD AGREEMENT REGARDING THE MOVEMENT AND PLACEMENT OF THE FRONT. THE FRESH TO STRONG WINDS WILL SPREAD EASTWARD IN THE WAKE OF THE FRONT WHILE VEERING TO THE NE-E BY SUN AFTERNOON. AHEAD OF THE FRONT THE PRES GRADIENT WILL BE RELATIVELY TIGHT WITH FRESH TO STRONG TRADES...POSSIBLY TO GALE FORCE NEAR THE NW COAST OF COLOMBIA BY SUN. WINDS WILL DIMINISH AND TURN E-SE IN THE NW CARIBBEAN MON AS HIGH PRES RIDGING BUILDS N OF THE AREA. IN THE TROPICAL N ATLC...MODERATE TRADES WILL PREVAIL THROUGH THU INCREASING TO FRESH THU NIGHT THROUGH MON AS THE PRES GRADIENT TIGHTENS. A MAJOR LONG PERIOD NE SWELL EVENT WILL OCCUR ACROSS THESE WATERS BEGINNING THU NIGHT AND THROUGH THE WEEKEND AND EVEN INTO EARLY NEXT WEEK WITH 8-11 FT SIGNIFICANT WAVE HEIGHTS EXPECTED. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: GLOBAL MODEL CONSENSUS. LATEST TAFB-NWPS USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. A WEAK HIGH PRES CENTER OF 1018 MB IS ANALYZED NEAR 28N74W WHILE A WEAK STATIONARY FRONT IS DRAPED ALONG 31N. OBSERVATIONS INDICATE MAINLY GENTLE TO MODERATE ANTICYCLONIC FLOW ACROSS THE BASIN... EXCEPT FOR MODERATE TO FRESH SW WINDS N OF 29N E OF 70W WHERE A COLD FRONT IS MOVING SE JUST TO THE E OF 65W. SEAS ARE MAINLY IN THE 3-5 FT RANGE OUTSIDE OF THE BAHAMAS...EXCEPT 5-7 FT IN THE AREA OF MODERATE TO STRONG SW WINDS. THE HIGH WILL SLIDE SE AND BECOME ELONGATED NW TO SE THROUGH THU WHILE THE THE FRONT WILL LIFT N AS A WARM FRONT. MODERATE TO LOCALLY FRESH E-SE FLOW WILL THEN PREVAIL LATE TONIGHT INTO THU MORNING AROUND THE RIDGING INCREASING TO FRESH TO STRONG IN THE NW PORTION THU NIGHT INTO FRI MORNING AHEAD OF THE NEXT COLD FRONT. THAT NEXT STRONG COLD FRONT WILL ENTER THE FAR NW PORTION AROUND 12 UTC FRI. IT WILL REACH A POSITION FROM NEAR 31N74W TO THE STRAITS OF FLORIDA FRI EVENING THEN FROM 31N68W TO N CENTRAL CUBA SAT MORNING THEN FROM 27N65W TO EASTERN CUBA SUN MORNING WHERE IT WILL STALL AND GRADUALLY BECOME DIFFUSE THROUGH MON. FRESH TO STRONG SOUTHERLY WINDS WILL SPREAD EASTWARD N OF 29N AHEAD OF THE FRONT...WITH FRESH TO STRONG NORTHERLY WINDS BEHIND IT. THE WINDS WILL DIMINISH IN THE NW PORTION BY SUN MORNING AS HIGH PRES BECOMES CENTERED OVER THE CAROLINAS IN THE WAKE OF THE FRONT. THE FRESH TO STRONG WINDS WILL GRADUALLY VEER AROUND TO THE NE-E SUN ACROSS THE REMAINDER OF THE BASIN WITH SEAS OF 7-10 FT EXPECTED NE AND E OF THE BAHAMAS. CONDITIONS WILL BE MOST HAZARDOUS IN AND NEAR THE GULF STREAM AND STRAITS OF FLORIDA AS COUNTER FLOW OF CURRENT TO THE NE WINDS WILL MAINTAIN SEAS THERE OF 8-9 FT THROUGH SAT NIGHT. THE HIGH CENTER WILL SHIFT WELL TO THE E BY EARLY NEXT WEEK WITH RIDGING DOMINATING THE BASIN BY THEN. EXPECT MODERATE TO FRESH RETURN FLOW N OF 22N AND FRESH TO LOCALLY STRONG E-SE WINDS S OF 22N FOR THE START OF NEXT WEEK. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... .GMZ023...SW GULF S OF 22N W OF 94W... GALE WARNING THU NIGHT INTO FRI. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 LEWITSKY. NATIONAL HURRICANE CENTER.