000 AGXX40 KNHC 050513 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 130 AM EDT THU APR 5 2007 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. NRN BRANCH OF THE WESTERLIES CONTINUES TO MAKE INRODES INTO THE AREA S OF 31N. ONE FAIRLY STRONG SHORTWAVE WAS ALONG 50W MOVING ESE WHILE A SECOND STRONG CLOSED MID LEVEL CIRCULATION WAS OVER THE ERN GREATLAKES MOVING SE. A THIRD SHORTWAVE WAS IN THE SRN BRANCH OVER THE NW GULF. ON THE SURFACE TONIGHT A COLD FRONT WAS OVER THE CENTRAL ATLC IN ASSOCIATION WITH THE FIRST SHORTWAVE. WEAK LOW PRES WAS OVER THE NW GULF ASSOCIATED WITH THE THIRD SHORTWAVE. WEAK HIGH PRES WAS NE OF THE BAHAMAS DRIFTING SE. LATER DAY 1 THE FIRST SHORTWAVE IS EXPECTED TO WEAKEN AS IT LIFTS AWAY FROM THE REGION ALONG 40W. THE LARGE CIRCULATION OVER THE ERN GREATLAKES MOVES E OFF THE NEW ENGLAND COAST WHILE THE SHORTWAVE OVER THE NW GULF MOVES TO THE E CENTRAL GULF. ON THE SURFACE LATER DAY 1 WINDS INCREASE OVER THE NRN GULF TO 25 KT AS HIGH PRES BUILDS SWD. LITTLE STRENGTHENING TO THE WEAK LOW PRES AS IT MOVES TO THE SE GULF. THE ATLC FRONT MOVES EWD TO NEAR 40W WITH 20 TO 25 KT SW WINDS. CARIB WINDS MOSTLY LIGHT TO MODERATE. FOR DAY 2 WHILE THE MID LEVEL FLOW BECOMES MORE WLY E OF 60W WITH THE DEPARTING SHORTWAVE..THE MID LEVEL FLOW TURNS MORE NWLY W OF 80W WITH A NEW SURGE OF COLD AIR INTO THE OH VALLEY. ON THE SURFACE DAY 2 THE GFS MODEL SHOWS THE WEAK LOW FROM THE ERN GULF LIFTING NE AND DEEPENING TO 1006 MB WHILE THE SHORTWAVE IS SHOWN TO WEAKEN ACCORDING TO THE MODEL. MID LEVEL HEIGHTS WILL BE FALLING W OF 70W AS THE SURGE OF COLD AIR HEADS SE THEREFORE THIS MAY BE WHAT STRENGTHENS THE SURFACE LOW. ANYWAY WINDS DECREASE OVER THE GULF TO 15 TO 20 KT BUT INCREASE OVER THE ERN CAIB AND ATLC E OF 75W TO 20 KT. OUTLOOK PERIOD... FOR DAY 3 MID LEVEL HEIGHTS CONTINUE TO FALL SLOWLY W OF 70W AS THE LARGE POOL OF COLD AIR ALOFT SETTLES OVER THE TN VALLEY. THE MID LEVEL FLOW TURNS MORE WLY AHEAD OF THIS SURGE. MID LEVEL RIDGING BUILDS OVER MID OCEAN ALONG 50W WITH APPROACH OF THE STRONG CYCLONIC CIRCULATION NOW OVER THE OH VALLEY. ON THE SURFACE DAY 3 THE ATLC LOW PRES EXITS THE REGION WITH A COLD FRONT SWINGING EWD TO 70W WITH 20 TO 25 KT WINDS N OF 28N. GULF WINDS REMAIN 15 KT BUT INCREASE W OF 90W AS PRES FALLS OVER NE MEX. CARIB WINDS STRONGEST OVER THE ERN PORTION WHERE THE ATLC RIDGE BUILDS SW. FOR DAY 4 A NEW SURGE OF COLD AIR ALOFT HEADS SE OVER THE CENTRAL PLAINS TIGHTENING THE MID LEVEL FLOW S OF 35N. THE MID ATLC RIDGE HOLDS ALONG 45 TO 50W WITH A WEAK MID LEVEL RIDGE OVER THE CARIB AREA. ON THE SURFACE DAY 4 LOW PRES FROM NE MEX MOVES INTO THE NW GULF AND A POLAR AIRMASS MOVES S OVER THE PLAINS THUS WINDS INCREASE OVER THE NW GULF TO 25 TO 30 KT. ELSEWHERE MOSTLY HIGH PRES WITH A WEAKENING COLD FRONT OVER THE ATLC FROM 31N59W TO 20N69W. CARIB WINDS MOSTLY LIGHT TO MODERATE. FOR DAY 5 A VIGOROUS SHORTWAVE DRIVES EWD OFF THE SE COAST WITH MID LEVEL HEIGHTS RISING SLOWLY W OF 90W. ON THE SURFACE DAY 5 THE GULF LOW CENTER MOVES NE TO NEAR 30N75W AS A 1008 MB LOW WITH WINDS TO 30 KT. THE POLAR AIRMASS MOVES INTO THE NW GULF AT 1020 MB WITH 15 TO 20 KT IN THE GULF. ELSEWHERE LITTLE CHANGE WITH HIGH PRES NEAR 32N38W EXTENDING SW TO 70W WITH THE USUAL TRADES OF 15 TO 20 KT. WARNINGS... ATLANTIC... NONE. CARIBBEAN... NONE. GULF OF MEXICO... NONE. FORECASTER RRG