000 AGXX40 KNHC 171750 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 145 PM EDT SAT MAR 17 2012 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLC AND SOUTHWEST N ATLC S OF 31N W OF 55W. GULF OF MEXICO... AN E-W RIDGE WILL EXTEND ALONG 31N THROUGH SAT THEN SHIFT FURTHER N SAT NIGHT THROUGH MON...THEN RETRACT E ON TUE ALLOWING A VERY CONVECTIVE COLD FRONT TO MOVE INTO THE NW GULF TUE AFTERNOON. GFS GUIDANCE HAS BEEN CONSISTENT ON TIMING OF FRONT AND STRENGTH OF THE POST FRONTAL CAA. SE WINDS WILL CONTINUE AT 10-15 KT ACROSS THE GULF...EXCEPT PULSE TO 15-20 KT OVER THE NW WATERS THIS AFTERNOON. THE GRADIENT WILL TIGHTEN THIS EVENING RESULTING IN SE 15-20 KT RETURN FLOW WHICH WILL SPREAD E ACROSS THE ENTIRE AREA AND CONTINUE THROUGH EARLY MON NIGHT. THE SE WINDS WILL CLOCK TO S AND INCREASE TO 20-25 KT LATE MON NIGHT INTO TUE JUST AHEAD OF THE APPROACHING COLD FRONT. EXPECT NLY FLOW TO INCREASE TO A MAX OF 30 KT BRIEFLY BEHIND COLD FRONT LATE TUE NIGHT DURING A SECONDARY NLY SURGE. GUIDANCE NO LONGER HINTING OF MINIMAL GALE CONDITIONS OVER THE NW PORTION OF ZONE GMZ082 AROUND SUNRISE WED. SEAS WILL GRADUALLY BUILD TO 10 FT IN THE SLY FLOW AHEAD OF THE FRONT AND MAINTAIN AT THESE HEIGHTS FOR A FEW HOURS BEHIND THE FRONT BEFORE SUBSIDING AS THE NLY FLOW ABRUPTLY SHUTTING OFF WELL W OF THE FRONT WED NIGHT. SOUTHWEST N ATLC S OF 31N W OF 55W... THE ATLC RIDGE EXTENDING E TO W ALONG 31N-32N WILL RETRACT E TONIGHT AND EARLY SUN AS A WEAK COLD FRONT APPROACHES...BUT STALLS JUST N OF THE NW WATERS ON MON. A PAIR OF N-S ORIENTATED LOW LEVEL TROUGHS EXTENDING FROM 23N-28N ALONG 73W AND 65W ARE EXPECTED TO FILL LATER THIS WEEKEND. THE GRADIENT WILL TIGHTEN MON WITH NE 15-20 KT WINDS CONTINUING OVER THE SOUTHERN WATERS THROUGH THU...AND ALSO INCREASE OVER THE NORTHERN PORTION WED AND THU. CARIBBEAN SEA AND TROPICAL N ATLC... ATLC RIDGE WILL MAINTAIN EASTERLY 15-20 KT WINDS ACROSS THE CARIBBEAN WATERS TO THE E OF 82W...EXCEPT 25 KT WITHIN ABOUT 90 NM OF NW COAST OF COLOMBIA. THE GRADIENT WILL RELAX SOME MORE ON MON NIGHT THROUGH TUE NIGHT BEFORE INCREASING AGAIN WED AND THU. GENERALLY NE-E WINDS 10-15 KT FORECAST ELSEWHERE WITH A NEW ROUND OF NLY SWELLS ARRIVING TO THE TROPICAL WATERS ALONG 22N TO THE N OF THE VIRGIN ISLANDS ON WED NIGHT...BUT SUBSIDING TO LESS THAN 8 FT BEFORE REACHING THE NE CARIBBEAN PASSAGES FRI. WARNINGS... GULF OF MEXICO... .NONE. .CARIBBEAN SEA AND TROPICAL N ATLC... .NONE. .SW N ATLC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER NELSON