000 AGXX40 KNHC 141755 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 155 PM EDT FRI MAR 14 2008 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. ATLANTIC... SHORT-TERM...WEAK PRES PATTERN WITH BROAD SLY FLOW IS CURRENTLY IN PLACE OVER THE W ATLC WATERS AS A DISSIPATING FRONTAL BOUNDARY BEGINS TO LIFT N OF THE AREA AND A SFC RIDGE BUILDS E-W ACROSS THE SRN BAHAMAS. THE UPPER LEVEL PATTERN REMAINS PROGRESSIVE AND AN ACTIVE SUBTROPICAL JET WILL AFFECT THE REGION WITH SEVERAL DISTURBANCES BEFORE THE PATTERN BECOMES MORE AMPLIFIED EARLY NEXT WEEK. FIRST SYSTEM AFFECTS THE AREA TONIGHT WITH SW WINDS INCREASING TO 20-25 KT BRIEFLY AHEAD OF A DISTURBANCE WHICH WILL QUICKLY LIFT NE OF THE AREA ON SAT. A BRIEF RESPITE COMES ON SAT BEFORE SW WINDS INCREASE OVER THE NW WATERS AGAIN SAT NIGHT BUT THIS TIME A LITTLE STRONGER. PRE-FRONTAL WINDS WILL INCREASE TO 20-30 KT OVER A LARGE AREA N OF 27N ON SUN BEFORE THE COLD FRONT MOVES OFF THE GEORGIA COAST DURING THE LATE MORNING HRS. WINDS WILL SHIFT NW/N BEHIND THE FRONT AND WILL REMAIN STRONG WITH 8-13 FT SWELLS MOVING INTO THE NRN WATERS BY SUN EVENING. EXTENDED...THE COLD FRONT CONTINUES TO MOVE SE THROUGH THE AREA SUN NIGHT WHILE ITS PARENT LOW BOMBS OUT NE OF THE AREA. MODEL GUIDANCE SUGGESTS THAT THE LOW WILL REMAIN CLOSE ENOUGH TO THE OFFSHORE AREA...AND THE PRES GRADIENT ON ITS BACKSIDE WILL BE STRONG ENOUGH FOR THE NW WINDS BEHIND THE FRONT TO INCREASE TO GALE FORCE SUN NIGHT AND MON N OF 29N E OF 70W. THE 06Z GFS ENSEMBLE RUN HAD A MAXIMUM CHANCE OF GALES AT 40% AND ALTHOUGH THE 12Z RUN WILL BE MONITORED FOR TRENDS...IT SEEMS TO BE A SURE CASE THAT GALES WILL DEVELOP IN THE COLD ADVECTION BEHIND THE FRONT AND CONTINUE OVER THE FAR NE WATERS THROUGH MON NIGHT. THIS SYSTEM IS EXPECTED TO PRODUCE A SIGNIFICANT LONG PERIOD SWELL FIELD WITH MAXIMUM SIG WAVE HEIGHTS BUILDING TO 24 FT OVER THE NE WATERS BY MON NIGHT...AND A LARGE AREA OF 10-20 FT ELSEWHERE NE OF THE BAHAMAS. BY TUE AND WED HIGH PRES WILL SLIDE SE FROM THE CAROLINAS ALLOWING WINDS TO DIMINISH ACROSS THE ERN/SRN WATERS. HOWEVER...THE HIGH MOVES E ON WED AND QUICKLY ALLOWS SLY WINDS TO INCREASE OFF THE N FLORIDA COAST AHEAD OF THE NEXT SYSTEM. **************************************************************** CARIBBEAN... SHORT-TERM...GENTLE TO MODERATE TRADES DOMINATE MUCH OF THE CARIBBEAN/TROPICAL N ATLC WATERS...BORDERING ON FRESH AT BEST OFF THE COASTS OF COLOMBIA AND VENEZUELA AS WELL AS OVER THE GULF OF HONDURAS. LITTLE CHANGE IS EXPECTED OVER THE NEXT DAY OR TWO AS A SURFACE RIDGE SLOWLY BUILDS N OF THE AREA ALONG 23N. ONLY NOTICEABLE CHANGE WILL BE A SLIGHT STRENGTHENING OF THE TRADES OVER THE CNTRL CARIBBEAN SAT NIGHT AND SUN AS THE RIDGE BECOMES ESTABLISHED. EXTENDED...THE W ATLC COLD FRONT MOVES INTO THE NRN TROPICAL N ATLC WATERS ON MON WITH WINDS SHIFTING N BEHIND THE BOUNDARY AND INCREASING TO 15-20 KT. THIS BIG STORY WILL BE LARGE LONG PERIOD N SWELLS WHICH WILL MOVE INTO THE AREA LATE MON AND TUE...WITH NWW3 GUIDANCE SHOWING SEAS IN THE 12-20 FT RANGE N OF 14N BY WED. THESE SWELLS WILL REACH THE ATLC PASSAGES LATE TUE 8-12 FT SEAS WILL BLEED THROUGH THE MONA AND ANEGADA PASSAGES INTO THE E CARIBBEAN ON WED. SEA CONDITIONS COULD BECOME QUITE CHAOTIC AS THE NLY SWELL S OF THE PASSAGES INTERACTS WITH ELY WIND WAVES GENERATED BY NE/E WINDS OF 15-20 KT. **************************************************************** GULF OF MEXICO... SHORT-TERM...SLY FLOW WILL CONTINUE OVER THE GULF WATERS AHEAD OF A SYSTEM DEVELOPING OVER TEXAS...INCREASING TONIGHT OFF THE TEXAS COAST THEN SHIFTING E ACROSS THE REST OF THE NRN GULF WATERS ON SAT AS THE SYSTEM MOVES E. THE COLD FRONT IS EXPECTED TO MOVE OFF THE TEXAS COAST EARLY SAT AFTERNOON BUT WINDS BEHIND THE BOUNDARY WILL BE QUITE WEAK...AND THE FRONT IS EXPECTED TO STALL FROM S/CNTRL FLORIDA TO TEXAS BY SUN. ELY WINDS WILL INCREASE TO 20 KT N OF THE FRONT ON SUN OFF THE TEXAS/LOUISIANA COASTS WHILE THE REMAINDER OF THE AREA WILL BE UNDER A LIGHTER WIND REGIME. EXTENDED...THE PATTERN BECOMES MORE ACTIVE SUN NIGHT AS STRONG RETURN FLOW DEVELOPS OVER THE WRN GULF WATERS...CONTINUING THROUGH TUE AND ALSO INCREASING TO AS HIGH AS 30 KT BY LATE MON. DUE TO THE LARGE AREA OF STRONG WINDS...NWW3 GUIDANCE SUGGESTS THAT SEAS COULD BUILD TO 17 FT OVER THE NW GULF ON TUE...WHILE THE UKMET IS VERY SIMILAR WITH 16 FT. WILL THEREFORE BEGIN TO ADJUST SEAS UPWARD DURING THAT PERIOD. WILL LIKELY CONTINUE TO HOLD OFF ON MENTION OF GALE CONDITIONS ALTHOUGH THEY COULD BE VERY NEAR THAT THRESHOLD...AND WILL WAIT FOR THE 12Z GFS ENSEMBLE RUN TO DETERMINE EXACT WORDING IN THE FCST. THE AREA OF STRONG WINDS BEGINS TO DIMINISH AND SHIFT EWD ON TUE BEFORE A COLD FRONT MOVES OFF THE TEXAS COAST. THERE REMAINS SOME MODEL TIMING DIFFERENCES WITH THE GFS/GFS ENSEMBLE RUNS ALMOST 12 HRS SOONER THAN THE OTHER GLOBAL MODELS BUT REGARDLESS THE FRONT SHOULD BE OFF BY TUE NIGHT. WILL FOLLOW THE GUN ENSEMBLE FOR WED...INDICATING NW/N WINDS 10-15 KT BEHIND THE FRONT. WARNINGS... ATLANTIC... NONE. CARIBBEAN... NONE. GULF OF MEXICO... NONE. FORECASTER BERG