000 AXNT20 KNHC 312342 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE MAR 31 2015 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 05N09W TO THE EQUATOR NEAR 18W. ISOLATED MODERATE CONVECTION IS FROM 03N- 07N BETWEEN THE PRIME MERIDIAN AND 03W...FROM 01N-04N BETWEEN 03W-06W...AND FROM 01N-04N BETWEEN 16W-20W. ...DISCUSSION... GULF OF MEXICO... MIDDLE TO UPPER LEVEL RIDGING IS NOTED ON WATER VAPOR IMAGERY OVER THE GULF BASIN WITH MOISTURE AND CLOUDINESS STREAMING OVER SOUTHERN TEXAS...EASTERN MEXICO...AND PORTIONS OF THE WESTERN GULF WATERS THIS EVENING. OTHERWISE...A SHORTWAVE IS NOTED WELL TO THE NORTH OF THE BASIN SLIDING SOUTHEASTWARD ACROSS THE SE CONUS BUT HAVING LITTLE INFLUENCE ON THE GULF. THE UPPER LEVEL RIDGING LARGELY SUPPORTS A SURFACE RIDGE ANCHORED BY A 1021 MB HIGH CENTERED OFF THE COAST OF THE FLORIDA PENINSULA NEAR 27N84W. OVERALL...FAIR WEATHER AND GENTLE TO MODERATE ANTICYCLONIC WINDS PREVAIL ACROSS THE GULF THIS EVENING. LOOKING AHEAD...THE RIDGING WILL HOLD ITS PLACE THROUGH WEDNESDAY WHILE LOW PRESSURE DEVELOPS ACROSS THE CENTRAL AND SOUTHERN U.S. PLAINS. THIS WILL RESULT IN AN INCREASED PRESSURE GRADIENT AND STRONGER S-SE RETURN FLOW ACROSS THE WESTERN GULF LATE WEDNESDAY INTO THURSDAY. THEREAFTER...AS THE LOW DEVELOPS AND EJECTS E-NE TOWARD THE OHIO RIVER VALLEY LATE THURSDAY INTO FRIDAY...THE ASSOCIATED COLD FRONT IS EXPECTED TO EMERGE OFF THE TEXAS AND LOUISIANA COASTS LATE FRIDAY NIGHT WITH FRESH TO STRONG N-NE WINDS ANTICIPATED IN WAKE OF THE FRONT DURING THE UPCOMING WEEKEND FOR THE NORTHERN GULF WATERS. CARIBBEAN SEA... BROAD MIDDLE TO UPPER LEVEL TROUGHING IS OVER THE SW NORTH ATLC REGION THAT DIPS A BROAD BASE OVER THE NORTH-CENTRAL CARIBBEAN THIS EVENING. THIS IS RESULTING IN PRIMARILY WEST TO SOUTHWESTERLY FLOW ALOFT OVER THE BASIN WITHIN MOSTLY DRY AIR AND OVERALL SUBSIDENCE. HOWEVER...AT THE SURFACE...CONVERGENT EAST-NORTHEASTERLY TRADES AND A STATIONARY FRONTAL BOUNDARY ANALYZED TO THE NORTHEAST AND ACROSS HISPANIOLA CONTINUE TO GENERATE WIDELY SCATTERED SHOWERS ACROSS MUCH OF THE NORTHERN PORTION OF THE BASIN...GENERALLY N OF 15N BETWEEN 67W-83W...WITH THE FRONTAL BOUNDARY CONTRIBUTING TO MUCH OF THE AREA IN THE VICINITY OF THE WINDWARD PASSAGE. OTHERWISE...MODERATE TO OCCASIONAL FRESH BREEZE CONDITIONS ARE TO BE EXPECTED OVERNIGHT INTO WEDNESDAY AS THE FRONTAL BOUNDARY BECOMES DIFFUSE TO THE NORTH OF HISPANIOLA AND THE TRADES PERSIST THROUGH THE REMAINDER OF THE WEEK. ...HISPANIOLA... A STATIONARY FRONT REMAINS DRAPED ACROSS THE REGION EXTENDING FROM 23N60W TO 19N73W. THIS FRONT CONTINUES TO BE THE FOCUS FOR WIDELY SCATTERED SHOWERS OCCURRING FROM 17N-22N BETWEEN 68W- 77W...INCLUDING HISPANIOLA THIS EVENING. LOOKING AHEAD...THE FRONTAL BOUNDARY WILL BECOME DIFFUSE THROUGH THURSDAY WITH LOW- LEVEL MOISTURE EVENTUALLY MOVING NORTH OF THE ISLAND WEDNESDAY...HOWEVER ANOTHER WEAKENING FRONTAL BOUNDARY WILL MOVE INTO THE REGION LATE THURSDAY INTO EARLY FRIDAY PROVIDING FOR INCREASED TRADES AND HIGHER PROBABILITY OF PRECIPITATION. ATLANTIC OCEAN... BROAD MIDDLE TO UPPER LEVEL TROUGHING IS OVER THE SW NORTH ATLC REGION THIS EVENING THAT SUPPORTS A WEAK COLD FRONT EXTENDING FROM BERMUDA NEAR 32N65W SW TO 28N76W. ISOLATED SHOWERS ARE OCCURRING WITHIN 60 NM EITHER SIDE OF THE FRONT AS IT CONTINUES TO WEAKEN ACROSS THE DISCUSSION AREA S OF 32N. OTHERWISE...THE REMAINDER OF THE SW NORTH ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A PAIR OF 1021 MB HIGHS...ONE CENTERED NEAR 27N66W AND THE OTHER CENTERED IN THE EASTERN GULF OF MEXICO NEAR 27N84W. FARTHER EAST...A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY NORTH OF THE AREA NEAR 40N43W THAT SUPPORTS A COLD FRONT ANALYZED FROM 32N43W SW TO 26N50W TO 23N57W WHERE IT BECOMES STATIONARY TO NORTHERN HISPANIOLA NEAR 20N71W. ISOLATED SHOWERS ARE OCCURRING WITHIN 75 NM EITHER SIDE OF THE COLD FRONT...HOWEVER WIDELY SCATTERED SHOWERS ARE OCCURRING WITHIN 60 NM SOUTH OF AND 180 NM NORTH OF THE STATIONARY FRONT. MUCH OF THIS SHOWER ACTIVITY IS ENHANCED BY THE AFOREMENTIONED BROAD TROUGHING TO THE NW WITHIN MAXIMUM DIFFLUENCE ALOFT. FINALLY...A SURFACE RIDGE PREVAILS ACROSS THE EASTERN ATLC ANCHORED BY A 1037 MB HIGH CENTERED NEAR 43N19W... HOWEVER A SHARP MIDDLE TO UPPER LEVEL TROUGH IS NOTED WITH AXIS FROM 35N32W TO A BASE NEAR 29N24W. THE STRONGER DYNAMICS ARE NEAR THE BASE OF THE TROUGH AND CONTINUE TO GENERATE POSSIBLE SCATTERED SHOWERS AND TSTMS FROM 28N-35N BETWEEN 19W-25W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN