000 AGXX40 KNHC 190729 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 230 AM EST TUE JAN 19 2010 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W GULF OF MEXICO... 1021 MB HIGH PRES NEAR 27N90W DOMINATES THE GULF AT THIS TIME...WITH LIGHT ANTICYCLONIC FLOW ACROSS MUCH OF THE REASON. SOUTHERLY WINDS ARE PICKING UP TO 15 KT IN THE NW GULF AS THE PRES GRADIENT BUILDS BETWEEN THE HIGH AND A NEW LOW PRES SYSTEM EXPECTED TO MOVE THROUGH THE ROCKIES INTO THE CENTRAL PLAINS TONIGHT. EXPECT THE SOUTHERLY RETURN FLOW TO PICK UP TO 20 KT IN THE WESTERN GULF WED AS A RESULT OF THE INCREASED PRES GRADIENT BETWEEN THIS SYSTEM AND THE HIGH PRES TO THE E. THE MODELS AGREE ON TURNING THE UPPER LEVEL FLOW MORE ZONAL AND PROGRESSIVE. THEY DIVERGE WITH THE SURFACE LOW TRACK FROM THE PLAINS INTO THE MID MISSISSIPPI VALLEY WED NIGHT AND THU AS A NEW SURFACE LOW BEGINS TO DEVELOP ON THE CAROLINA COAST ALONG THE WARM FRONT AHEAD OF THE LOW. THE GFS HAS COME INTO BETTER AGREEMENT WITH THE OTHER MODELS ON THE MAIN LOW TRACK. IT APPEARS TO HAVE MOVED TOWARD THE MODEL CONSENSUS WITH A TRACK THAT IS SOUTH OF THE ECMWF/UKMET BUT NORTH OF THE NOGAPS...AND THE GFS NO LONGER DEVELOPS GALE FORCE WINDS WITHIN THE SOUTHERLY FLOW AHEAD OF THE SYSTEM IN THE N CENTRAL AND NE GULF. DIFFERENCES ARISE ON THE CAROLINA COAST AMONG THE MODELS BY THU NIGHT THAT ARE DISCUSSED IN THE SW N ATLC SECTION BELOW...BUT THE BASIC GIST IS THAT THE GFS MAY BE CRANKING UP THIS LOW A BIT TOO QUICKLY...SO A BLEND OF ITS SOLUTION AND THE ECMWF IS PREFERRED THERE AND WITH THE SW FLO OVER THE EASTERN GULF ON FRI AS A RESULT. THE MODELS AGREE ON INCREASING RETURN FLOW IN THE WESTERN GULF SAT IN RESPONSE TO THE NEXT SYSTEM EMERGING IN THE PLAINS. CARIBBEAN AND TROPICAL N ATLC W OF 55W... INCREASING HIGH PRES OVER BEHIND THE COLD FRONT OVER THE SW N ATLC IS INCREASING THE PRES GRADIENT BETWEEN IT AND CLIMATOLOGICAL LOW PRES OVER COLOMBIA...BRINGING A RETURN OF STRONG EASTERLY TRADES TO THE CENTRAL CARIBBEAN. ASCAT PASSES FROM 0134 AND 0314 UTC IN ADDITION TO WINDSAT FROM 2240 SHOW TRADES IN THE 20 TO 25 KT RANGE NEAR THE COAST OF COLOMBIA. THERE ARE A FEW SHIP REPORTS IN THE AREA THAT SUGGEST THESE WINDS ARE TOO LOW. BOTH OF THESE SCATTEROMETERS HAVE A LOW BIAS FOR WINDS THIS STRONG. THEREFORE...WILL SHOW WINDS IN THE 25 TO 30 KT RANGE HERE FOR THE NEXT HIGH SEAS PACKAGE. THE HIGH PRES TO THE NORTH SHIFTS EAST INTO THE ATLC BY WED NIGHT. LOOK FOR STRONG WINDS TO EXPAND ACROSS THE CENTRAL AND SW CARIBBEAN AS THE RIDGE TO THE NORTH BUILDS THROUGH THU. MEANWHILE...SE FLOW IN THE NW CARIBBEAN INCREASES TO 20 KT WED NIGHT AND THU AHEAD OF THE NEXT SYSTEM IMPACTING THE GULF OF MEXICO. AS THE SYSTEM SHIFTS EASTWARD....IT ALSO SHIFTS THE RIDGE EASTWARD...BRINGING WEAKENING THE TRADES AGAIN FRI/SAT. SW N ATLC S OF 31N W OF 55W... A COLD FRONT REMAINS STRETCHED FROM 31N65W TO 23N76W WITH A SECONDARY COLD FRONT WITHIN 240 NM NW OF IT. THE 0136 UTC ASCAT PASS SHOWS WINDS TO 25 KT BEHIND THE SECONDARY COLD FRONT N OF 29N E OF 72W. THE NORTHERN PORTION OF THIS FRONT WILL MOVE E OUT OF THE AREA TODAY WHILE THE SOUTHERN END STALLS NORTH OF HISPANIOLA TODAY THROUGH THU. EXPECT THE HIGH PRES BEHIND THE FRONT TO BECOME THE DOMINATING WEATHER FEATURE OVER MUCH OF THE AREA TONIGHT AND WED WITH LIGHT FLOW AND NW SWELL SUBSIDING THROUGH THAT PERIOD. MODEL DIFFERENCES COME IN TO PLAY BY THU NIGHT OVER THE CAROLINA COAST...WITH THE GFS CRANKING UP A COASTAL LOW ALONG THE WARM FRONT AHEAD OF THE SYSTEM PASSING THROUGH MISSISSIPPI/OHIO VALLEYS FASTER THAN THE OTHER MODELS. WHILE ALL OF THE MODELS AGREE ON DEVELOPING THIS LOW AND MOVING IT OFFSHORE WELL NORTH OF THE AREA...PREFER TO SLOW DOWN THE GFS DEVELOPMENT OF THE SYSTEM BY 6 TO 12 HOURS TO BE MORE IN LINE WITH THE MODEL CONSENSUS. GALE FORCE WINDS ARE EXPECTED IN THE SOUTHERLY FLOW SE OF THE SYSTEM FRI AND SAT. WARNINGS... ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER SCHAUER