000 AGXX40 KNHC 070853 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 430 AM EDT FRI MAY 07 2010 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W GULF OF MEXICO... THE OLD FRONTAL BOUNDARY ACROSS THE NE GULF HAS DETERIORATED TO A WEAK SHEAR LINE AND WAS SEEN DRIFTING N INTO THE OUTER COASTAL WATERS OF THE NE GULF COAST STATES FROM NEAR 26.5N90W TO JUST S OF CEDAR KEY. LLVL RIDGING WAS SHIFTING W INTO THE GULF UNDERNEATH THIS OLD BOUNDARY AND ALSO FORCING THE REMNANTS OF THE NOW DIFFUSE TROUGH THAT WAS W OF THE YUCATAN THIS MORNING INTO THE SW GULF ALONG 93W. THUS ANTICYCLONIC FLOW WAS DOMINATING THE SE HALF OF THE BASIN E AND SE OF THESE TWO FEATURES. THIS ANTICYCLONIC FLOW WAS BRIDGING OVER THESE BOUNDARIES AS RETURN FLOW CONTINUED ACROSS THE N AND NW GULF IN ADVANCE OF THE APPROACHING FRONTAL SYSTEM ACROSS THE CENTRAL PLAINS. OBS OFF THE TEXAS COAST INDICATING 15-20 KT SLY FLOW WITH SEAS INCREASING FROM 1 FT AT BUOY 42002 TO 4-5 FT NEAR THE COAST. AS THE REMNANTS OF THE OLD TROUGH ACROSS THE SW GULF SHIFT WNW THIS MORNING...15-20 KT SLY FLOW IS FORECAST BECOME ENTRENCHED ACROSS THE BASIN W OF 90W BY AFTERNOON...AND SE TO S AT 5-10 KT BETWEEN 85W AND 90W. THIS WILL ALLOW SEAS TO REMAINS AT 4-6 FT ACROSS THE FAR W AND NW GULF THROUGH THIS EVENING... WHILE THE DIURNAL TROUGH THAT DEVELOPS LATE ACROSS THE YUCATAN AND ASSOCIATED FRESH NELY FLOW WILL YIELD SEAS 5 TO 6 FT OFF THE NW COAST THERE. THIS YUCATAN DIURNAL SEABREEZE WILL CONTINUE TO FLARE TO 20 KT LATE AFTERNOON THROUGH EARLY NIGHT THROUGH THE WEEKEND. MEANWHILE A WEAK HIGH CENTER JUST OFF THE SW COAST OF FLORIDA WILL PRODUCE LIGHT AND VARIABLE WINDS THERE WITH SEAS GENERALLY SLIGHT ACROSS MOST OF THE EASTERN GULF THROUGH TONIGHT. THE COLD FRONT ACROSS THE GREAT PLAINS IS STILL FORECAST TO DROP INTO THE GULF COASTS SAT NIGHT AND REACH THE COASTS AROUND MIDNIGHT. LOW TO MID LEVEL RIDGING ACROSS THE WRN GULF WILL BLOCK THE SRN PROGRESS OF FRONT AND ALLOW IT TO DRAPE OVER THE RIDGE AND SPILL SE INTO THE NE GULF LATE SAT NIGHT-EARLY SUN MORNING THEN SINK S FROM NEAR S CENTRAL LOUISIANA TO NEAR TAMPA BAY AREA SUN EVENING. THIS WILL PRODUCE A BRIEF PERIOD OF LIGHT TO MODERATE NLY AND OFFSHORE FLOW OFF THE LA-MS-FL PANHANDLE COASTS SAT NIGHT BEFORE VEERING NE TO E SUN. HOWEVER THIS FLOW WILL LIKELY NOT BE SUFFICIENT TO PROVIDE MUCH NLY PUSH FOR THE OIL WITHIN THE COASTAL ZONES THERE. RETURN FLOW WILL THEN BEGIN ACROSS THE W AND NW GULF SUN AFTERNOON AHEAD OF NEXT FRONTAL SYSTEM MOVING INTO THE CENTRAL PLAINS. THE DOMINANT HIGH ACROSS THE REGION IS FORECAST TO BE ALONG THE MID ATLC STATES BY MON AND ALLOW FOR A MORE UNIFORM ANTICYCLONIC FLOW TO BECOME ESTABLISHED ACROSS THE WHOLE BASIN...WITH E-SE WINDS 10-15 KT ACROSS THE E GULF AND SE-S WINDS 15-20 KT ACROSS THE W HALF MON...VEERING SLIGHTLY MON NIGHT AND INCREASING. THIS RETURN FLOW IS FORECAST TO PERSIST THROUGH WEDNESDAY AND WILL MAINTAIN A MODERATE TO FRESH SE TO S RETURN FLOW ACROSS THE ENTIRE BASIN...AND LIKELY BEGIN TO FORCE OIL ACROSS THE SE GULF ASHORE ALONG THE LOUISIANA...MISSISSIPPI...AND ALABAMA COASTS. SW N ATLANTIC S OF 31N W OF 55W... DOUBLE BARREL HIGHS WERE LOCATED WITHIN THE ATLC RIDGE...S AND SE OF BERMUDA...AT NEAR 1021 MB...AND CONTINUE TO SHIFT SLOWLY NE IN RESPONSE TO UPPER TROUGH OFF FLORIDA COAST INCHING SLOWLY EWD. THE BROAD BUT WEAK RIDGE AXIS EXTENDS NE TO SW AND ACROSS SRN FLORIDA CONNECTING WITH THE WEAK HIGH ACROSS THE SE GULF. REMNANTS OF THE FRONTAL BOUNDARY APPEAR LARGELY DIFFUSE IN STLT IMAGERY THIS MORNING WITH LLVL CONVERGENCE AND SCATTERED SHOWERS OCCURRING FARTHER DOWNSTREAM N OF 29N AND E OF 75W. S OF THE RIDGE MODERATE ELY TRADES ARE OCCURRING S OF 22N WERE RECENT ASCAT PASSES...AND WERE 15 TO 20 KT ACROSS THE NRN PERIPHERY OF THREE LLVL VORTS THAT HAVE DEVELOPED PAST 48 HOURS ALONG THE OLD SHEAR LINE THAT HAS LIFTED NW ACROSS THE NE CARIBBEAN. THE RIDGE WILL CONTINUE TO SHIFT E-NE THROUGH THE WEEKEND AS THE COLD FRONT DROPS INTO THE NE GULF AND WEAKEN THE TRADES. THE COLD FRONT IS FORECAST TO MOVE OFF THE NE FLORIDA COAST LATE SAT AFTERNOON AND INTO THE NW WATERS SAT EVENING...WITH A VERY BRIEF PERIOD OF 15-20 KT NWLY FLOW BEHIND THE FRONT SAT NIGHT. UPPER SUPPORT WILL LIFT QUICKLY OUT TO THE NE AND ACROSS THE NW ATLC AND LEAVE A 1028 MB HIGH ACROSS THE TN VALLEY TO SLIDE NE AND BRING QUICKLY VEERING FLOW BEHIND THE FRONT SUN...WITH THE FRONT REACHING FROM BERMUDA TO THE NW BAHAMAS BY MIDNIGHT SUNDAY NIGHT. WINDS AND SEAS WILL GENERALLY REMAIN MILD ELSEWHERE. CARIBBEAN SEA AND TROPICAL N ATLC... THE WRN MOST OF THE THREE LLVL VORT CENTERS MENTIONED ABOVE AND ASSOCIATED WITH THE OLD SHEAR LINE ACROSS THE NE CARIB HAS BEEN PICKED UP BY THE EASTERLIES AND IS MOVING W ACROSS THE CENTRAL CARIB THIS MORNING. THIS HAS COMBINED WITH THE TIGHTENED PRES GRADIENT BETWEEN THE WEAK HIGH ACROSS THE SE GULF AND LOW PRES ACROSS S AMERICA EXPAND THE 20 KT TRADES ACROSS THE CENTRAL AND SW CARIBBEAN PAST 24 HOURS...AS WELL AS TO EXPAND THE AREA OF 25 KT WINDS OFF OF COLOMBIA PER A 0240 UTC ASCAT PASS. SEAS THERE LIKELY APPROACHING 9 FT ATTM. THIS PRES PATTERN WILL PREVAIL THROUGH SUN WITH FRESH TRADES REMAINING ACROSS THE CENTRAL AND SW CARIB. THE GRADIENT WILL BECOME ENHANCED SUN NIGHT THROUGH TUE NIGHT AS THE GULF FRONT MOVES ACROSS THE NE GULF AND IS FOLLOWED BY THE BUILDING HIGH MON-TUE-WED. THIS WILL BRING FRESH TO STRONG E-NE TRADES TO MOST OF THE BASIN BY TUE AND BUILD SEAS GRADUALLY TO 9-12 FT W OF 72W. TROPICAL WAVES HAVE BECOME EVIDENT IN THE PAST WEEK MOVING ACROSS THE TROPICAL ATLC. A LOW LAT WAVE ANALYZED IN THE VICINITY OF 45W IS EXPECTED TO MOVE INTO THE TROPICAL ATLC WATERS SUN EVENING AND NIGHT AND BRING 20 KT ELY TRADES S OF 15N AND SEAS 6-7 FT THOUGH MON. WARNINGS... ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER STRIPLING