000 AGXX40 KNHC 031819 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 220 PM EDT MON MAY 03 2010 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W GULF OF MEXICO... OBSERVATIONS IN THE CENTRAL GULF OF MEXICO INCLUDING THE WINDSAT PASS FROM 1226 UTC CONFIRM THE MAXIMUM WINDS IN THE GULF HAVE DIMINISHED TO 15-20 KT THIS AFTERNOON. THIS IS CONSISTENT WITH THE MODEL FORECASTS. THE 06Z WAVEWATCH RUN USED FOR THE MANUAL PROGS WAS AS MUCH AS 3 FT HIGHER THAN THE OBSERVATIONS AT 1200 UTC IN THE ENVIRONMENTALLY SENSITIVE NORTH CENTRAL GULF...SHOWING 9 FT SEAS WHERE SEVERAL OBSERVATIONS ONLY HAD SEAS TO 6 FT. PERHAPS IT IS OVERDOING THE SE SWELL. THE 00Z ECMWF WAVE MODEL WAS IS MUCH BETTER AGREEMENT WITH THESE OBSERVATIONS...BUT WAS UNDERDONE WITH THE MAXIMUM WAVE HEIGHTS FOUND FARTHER S IN THE CENTRAL GULF. THE ATMOSPHERIC MODELS AGREE THAT THE PATTERN WILL BECOME LESS AMPLIFIED OVER THE NEXT FEW DAYS. AT THE SURFACE...THE HIGH PRESSURE SYSTEM OVER THE ATLC WILL REMAIN RELATIVELY STATIONARY BUT WEAKEN WHILE THE NORTHERN PORTION OF THE COLD FRONT GRADUALLY MAKES ITS WAY INTO N FL...PUSHING INTO THE FLORIDA BIG BEND OVERNIGHT TUE NIGHT WHILE THE DISSIPATING FRONTAL REMNANTS STAY ANCHORED OVER THE SW GULF. THE BOUNDARY WILL DISSIPATE OVER FORECAST WATERS ON WED. LIGHT WINDS AND SEAS OF 4 FT OR LESS ARE ON TAP FOR WED AND MUCH OF THU...BUT LOOK FOR TROUGHING TO BUILD OVER TEXAS AND EASTERN MEXICO ON THU THAT WILL BRING 20 KT SOUTHERLY RETURN FLOW TO THE NE GULF COAST THU NIGHT INTO FRI. THE MODELS AGREE ON CARRYING A FRONT THROUGH TEXAS ON FRI...BUT THE GFS AND NOGAPS BRING THE FRONT TO THE COAST AND ARE CONSIDERABLY FASTER WITH THE ANCHOR LOW PASSING S OF THE GREAT LAKES COMPARED TO THE ECMWF...CMC...AND UKMET WHICH ALLOW THE FRONT TO STAY OFFSHORE THROUGH FRI NIGHT. THE MODELS TRADITIONALLY HAVE A PROBLEM HANDLING THESE TRANSITIONS FROM AMPLIFIED FLOW TO ZONAL FLOW. FOR NOW...WENT WITH A BLEND OF SOLUTIONS...BUT WILL NOT BE SURPRISED IF THE FASTER GFS/NOGAPS PANS OUT CONSIDERING THE FAST FLOW ALOFT THAT IS EXPECTED. SW N ATLANTIC S OF 31N W OF 55W... SLY RETURN FLOW TO 20 KT WILL BUILD TONIGHT IN NW WATER DUE TO THE PRES GRADIENT BETWEEN THE FRONT IN THE GULF OF MEXICO AND THE 1025 MB HIGH IN NE WATERS NEAR 30N66W. IN ADDITION...A FRESH BREEZE IS FOUND ON THE SOUTHERN PERIPHERY OF THIS HIGH...PARTICULARLY S OF 23N. THESE WINDS WILL SHIFT S BUT INTO TUE AS THE HIGH REMAINS STATIONARY. THE HIGH FINALLY BEGINS ITS SLOW DRIFT E INTO THE CENTRAL ATLC LATE TUE/WED ALLOWING THE FRESH WINDS IN S WATERS TO DIMINISH AND THE GULF COLD FRONT TO MOVE INTO NW WATERS. THE MODELS ARE IN REASONABLE AGREEMENT ON STALLING THIS FRONT OFF THE NE FL COAST WED BEFORE GRADUALLY DISSIPATING THE SYSTEM THROUGH FRI AS A NEW HIGH PRES CENTER MOVES E OVER BERMUDA AND EVENTUALLY MERGES WITH THE ESTABLISHED HIGH IN THE CENTRAL ATLC. CARIBBEAN SEA AND TROPICAL N ATLC... TIGHT PRES GRADIENT BETWEEN HIGH PRES OVER THE SW ATLC AND LOWER PRES OVER THE WESTERN GULF OF MEXICO IS PRODUCING SE WINDS TO 25 KT ACROSS THE NW CARIBBEAN MAINLY W OF 84W WITH WINDS OCCASIONALLY REACHING 30 KT IN THE YUCATAN CHANNEL. WINDS ARE EXPECTED TO DIMINISH TO 15 TO 20 KT TONIGHT WITH SEAS SUBSIDING TO AROUND 5 FT LATE TUE. THE STATIONARY SUBTROPICAL HIGH WILL ALLOW FRESH TO MODERATE TRADES TO CONTINUE IN THE CENTRAL CARIBBEAN THROUGH TUE AND WEAKEN ON WED AND THU AS THE HIGH DRIFTS E. THE WEAKENING SHEAR AXIS OVER THE N PORTION OF THE SW TROPICAL ATLC AND THE N CENTRAL CARIBBEAN WILL BEGIN TO DISSIPATE TUE. NE WINDS TO 20 KT CAN BE FOUND N IN THE ATLC OF THE BOUNDARY THROUGH TUE MORNING. THIS SHEAR LINE IS THE FOCUS FOR LOW TOPPED SHOWERS PRIMARILY OVER PUERTO RICO AND EXTENDING S OF HISPANIOLA. THESE SHOWERS SHOULD BEGIN TO BREAK UP BY WED AS THE LOW LEVEL BOUNDARY WEAKENS...BUT THERE WILL STILL BE SOME CHANCE OF SHOWERS OVER THE NE CARIBBEAN THROUGH THE WEEK. WARNINGS... ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER SCHAUER