000 AGXX40 KNHC 210604 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 104 AM EST WED JAN 21 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: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. TAFB NWPS USED FOR WAVE HEIGHTS. MED CONFIDENCE. A NNW-SSE TROUGH IS ALONG ABOUT 87W WITH A 1015 MB SURFACE HIGH AT 24N92W. HIGH PRES IS STRENGTHENING N OF THE AREA AND BUILDING S ACROSS THE WESTERN GULF AND WILL PUSH THE TROUGH E TODAY TO THE FAR EASTERN WATERS WHERE IT WILL MOSTLY LOSE IDENTITY LATE TONIGHT. GUIDANCE HAS CHANGED SOMEWHAT OVER THE PAST 24 HOURS AND NOW MOVES A SURFACE LOW INTO THE FAR NW WATERS ON THU AFTERNOON WITH THE LOW RACING OFF TO THE NE ON THU NIGHT AND INLAND THE FL PANHANDLE EARLY FRI MORNING. THE LOW WILL DRAG A COLD FRONT ACROSS THE THE CENTRAL GULF MIDDAY ON FRI...AND PASS SE OF THE AREA EARLY SAT. THE NEW TRACK OF THE LOW WILL LIMIT THE AREA OF STRONG NE WINDS OVER THE NW WATERS TO A SMALLER AREA ON THU NIGHT...BUT INCREASE OF THE AFFECTED AREA OF NORTHERLY 20- 30 KT OVER THE W-CENTRAL GULF ON FRI...AS WELL AS PROVIDE A MUCH LARGER AREA OF POST-FRONTAL NW FLOW OVER THE N-CENTRAL AND NE GULF ON FRI NIGHT AND SAT. GUIDANCE ONLY HINTS AT MINIMAL GALE NEAR 23N96W LATE FRI...SO STILL HOLDING OFF ON POSTING POSSIBLE WARNINGS TO SEE IF FUTURE MODEL RUNS INCREASE THE CAA AND AT LEAST A WARNING FOR FREQUENT GALE FORCE GUSTS IS NECESSARY. EXPECT THIS FRONT TO BE VERY CONVECTIVE THUS POPULATED WEATHER GRIDS OUT TO DAY 4 TO GIVE MORE PLANNING LEAD TIME. EXPECT A RIDGE FROM 22N98W TO THE FL STRAITS ON SUN WITH ANTICYCONIC 10- 15 KT FLOW ACROSS THE ENTIRE GULF. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. TAFB NWPS USED FOR WAVE HEIGHTS. MED-HIGH CONFIDENCE. NE-E 20-25 KT WINDS WITH 7-11 FT SEAS EXPECTED TO DEVELOP WITHIN ABOUT 150 NM OF THE NW COAST OF COLOMBIA LATE EACH NIGHT THROUGH EARLY EACH MORNING THROUGH SAT...THEN GUIDANCE SHIFTS THE AFFECTED AREA A LITTLE FURTHER N ALONG COLOMBIA AND INCLUDES THE EXTREME NW VENEZUELA COASTAL WATERS ON SUN. ELSEWHERE ACROSS THE SW CARIBBEAN...AND EASTERLY 10-15 KT CONDITIONS ACROSS THE E CARIBBEAN AND TROPICAL ATLC WATERS THROUGH THE PERIOD. NE 15-20 KT CONDITIONS EXPECTED IN THE WINDWARD PASSAGE ON THU... OTHERWISE 5-10 KT EASTERLY WINDS FORECAST FOR THE NW CARIBBEAN TILL EARLY THU WHEN THE GRADIENT WILL SUPPORT 10-15 KT E-SE WINDS THROUGH FRI. A COLD FRONT WILL ENTER THE YUCATAN CHANNEL EARLY SAT WITH NW-N 15-20 KT WINDS BY LATE SAT AND SPREADING E ACROSS THE NW CARIBBEAN ON SUN. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. TAFB NWPS USED FOR WAVE HEIGHTS. MED-HIGH CONFIDENCE. A SURFACE HIGH IS CURRENTLY NEAR 30N67W WITH A RIDGE EXTENDING WSW TO PORT CANAVERAL FL. THE S-SW FLOW N OF THE RIDGE IS AT 15- 20 KT OVER THE NW WATERS AHEAD OF A COLD FRONT ACCOMPANIED BY NW 10-15 KT WINDS. THE FRONT SHOULD REACH FROM BERMUDA TO CENTRAL CUBA THU AFTERNOON. THE NORTHERN SEGMENT WILL CONTINUE E PASSING E OF 55W ON SAT. THE SOUTHERN SEGMENT WILL DRIFT N ON FRI AHEAD OF THE NEXT STRONGER COLD FRONT. THE SOUTHERLY FLOW WILL INCREASE TO 20-30 KT N OF THE BAHAMAS ON FRI NIGHT WITH MINIMAL GALE CONDITIONS LIKELY JUST N OF THE AREA. THE POST FRONTAL W-NW FLOW EXPECTED AT 20-30 KT INTO EARLY SAT NIGHT...THEN DIMINISHING TO 20 KT. THE FRONT SHOULD REACH FROM BERMUDA TO THE CENTRAL BAHAMAS EARLY SUN...AND BEGIN TO STALL FROM 27N65W TO THE WINDWARD PASSAGE ON SUN NIGHT. EXPECT THIS FRONT TO BE VERY CONVECTIVE THUS POPULATED WEATHER GRIDS OUT TO DAY 4 TO GIVE MORE PLANNING LEAD TIME. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 NELSON. NATIONAL HURRICANE CENTER.