000 AGXX40 KNHC 181701 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 100 PM EDT FRI APR 18 2008 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. UPPER LEVELS... STRONG SHORTWAVE OVER THE CENTRAL U.S. WILL MOVE TO THE MID ATLANTIC COAST MONDAY THEN MOVE SOUTHEAST OVER THE NORTHERN PART OF THE ATLANTIC AREA WEDNESDAY. INITIALLY A BROAD RIDGE IS OVER THE CARIBBEAN WITH WEAK WESTERLIES NORTH OF THE GREATER ANTILLES. THIS PATTERN WILL EVOLVE TO A BROAD TROUGH OVER THE AREA EAST OF 80W AND A RIDGE WEST OF 80W BY SUNDAY. THIS PATTERN WILL AMPLIFY THROUGH WEDNESDAY. SURFACE... RIDGE ALONG 31N WILL WEAKEN IN THE GULF AS WEAK COLD FRONT MOVES ACROSS THE GULF OF MEXICO AND BECOMES DIFFUSE AS IT CROSSES FLORIDA SUNDAY. A WEAK PRESSURE PATTERN WILL BE OVER THE AREA SUNDAY THROUGH WEDNESDAY EXCEPT FOR A MODERATE RIDGE OVER THE SOUTHEAST U.S. MONDAY THROUGH WEDNESDAY WITH SOUTHERLY RETURN FLOW IN THE WESTERN GULF OF MEXICO. STRONG TRADES IN THE CARIBBEAN WILL WEAKEN TO NEAR NORMAL SATURDAY AND TO LESS THAN NORMAL MONDAY THROUGH WEDNESDAY. TRADES IN THE TROPICAL ATLANTIC WILL BE NEAR NORMAL FALLING TO LESS THAN NORMAL SATURDAY THROUGH WEDNESDAY. WARNINGS... ATLC... NONE. CARIBBEAN... NONE. GULF OF MEXICO... NONE. .FORECASTER LL. TROPICAL PREDICTION CENTER.