000 AGXX40 KNHC 250548 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 130 AM EST THU MAR 25 2004 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. RELATIVELY STRONG ZONAL FLOW CHARACTERIZES THE UPPER FLOW ACROSS N AMERICA TONIGHT. A WEAK SHORTWAVE TROUGH EMBEDDED IN THE FLOW WAS OVER TEXAS MOVING E. WATER VAPOR SHOWS THE TROUGH MAY BE STRONGER THAN THE MRF MODEL SHOWS. STRONG SURFACE RIDGE COVERS MOST OF THE MARINE AREA W OF A STATIONARY FRONT 31N55W TO 20N70W. VERY STRONG NE WINDS ALL SECTIONS OF ATLC WATERS W OF FRONT WITH SEAS TO 16 FT. CARIBBEAN AND GULF WITH ABOVE NORMAL WINDS. SHORT WAVE WEAKENS DAY 2 OVER LOWER MS VALLEY. UPPER LEVEL TROUGHING TRYING TO SET UP E OF 60W. SOME SLIGHT WEAKENING OF PRESSURE GRADIENT W OF FRONT DAY 2 BUT WINDS REMAIN 25 TO 30 KT N OF 20N. OUTLOOK PERIOD... ZONAL FLOW BECOMES UNSTABLE DAY 3 A TROUGHING SETS UP OVER WESTERN US AND OVER ATLC WITH RIDGE BUILDING IN BETWEEN. ATLC FRONT DRIFTS E AND WEAKENS TO A TROUGH. HIGH PRESSURE W OF FRONT CONTINUES TO SLOWLY WEAKEN WITH WINDS LOWERING TO 20 TO 25 KT RANGE N OF 20N. GULF WINDS REMAIN ABOVE NORMAL WHILE CARIBBEAN S OF 20N MOSTLY LIGHT TO MODERATE. DAY 4 FINDS RIDGE OVER CENTRAL US BECOMING MORE PRONOUNCED WHILE ATLC UPPER TROUGH BUILDS BACK INTO CARIBBEAN. AT SURFACE THE ATLC RIDGE BUILDS W IN RESPONSE TO UPPER RIDGE FURTHER W. WINDS REMAIN MODERATE N OF 20N AND W OF 60W. LITTLE CHANGE TO UPPER PATTERN DAY 5 WITH LARGE AMPLITUDE TROUGH COVERING SW ATLC WITH RIDGE HOLDING FIRM OVER W GULF. A WEAK COLD FRONT DROPS INTO THE NW GULF DAY 5 WITH 20 KT WINDS OTHERWISE PRESSURE GRADIENT WEAKENS SOME OVER REMAINDER OF AREA. WARNINGS... GALE WARNING ATLC N OF 27N W OF STNRY FRONT 31N55W 27N59W TO 65W TIL 18Z 26 MAR. FORECASTER RRG