000 AXNT20 KNHC 281024 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON APR 28 2014 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 07N12W TO 03N17W TO 01N27W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 01N28W TO 03S39W. CLUSTERS OF MODERATE/ISOLATED STRONG CONVECTION ARE FROM 01S-07N BETWEEN 12W-28W. ISOLATED MODERATE CONVECTION IS FROM 05S-03N W OF 30W. ...DISCUSSION... GULF OF MEXICO... WESTERLY FLOW IS ACROSS THE BASIN ALOFT WITH WATER VAPOR IMAGERY INDICATING THE PRESENCE OF DRY AIR OVER THE WESTERN GULF. A MIDDLE TO UPPER LEVEL RIDGE EXTENDING FROM THE GREAT LAKES TO NORTHERN CUBA IS GENERATING DIFFLUENCE ACROSS THE EASTERN GULF...THUS SUPPORTING SCATTERED SHOWERS FROM 23N-29N E OF 85W. RADAR IMAGERY SHOW ISOLATED SHOWERS OVER THE NW GULF N OF 27N W OF 93W. A VIGOROUS MIDDLE TO UPPER LEVEL LOW CENTERED OVER THE CENTRAL PLAINS SUPPORT A FRONTAL SYSTEM OVER THE CENTRAL U.S...INCLUDING THE NEXT COLD FRONT THAT WILL ENTER THE NW BASIN LATE TUE MORNING. A TIGHT PRESSURE GRADIENT ASSOCIATED WITH THE FRONTAL SYSTEM HAS INCREASED THE S-SE WIND FLOW W OF 87W TO 20- 25 KT. RETURN FLOW ASSOCIATED WITH A WEAK SURFACE RIDGE ANCHORED OVER THE SW N ATLC SUPPORT LIGHTER WINDS OF 10-15 KT ELSEWHERE ACROSS THE GULF. WINDS ARE EXPECTED TO SHIFT N-NE WEST OF THE NEXT COLD FRONT TUESDAY INTO WEDNESDAY AS SURFACE RIDGING BUILDS SOUTHEASTWARD INTO THE SOUTHERN PLAINS AND ALONG THE MEXICO COAST. CARIBBEAN SEA... NORTHWESTERLY TO WESTERLY FLOW ALOFT PREVAILS OVER THE CARIBBEAN WITH WATER VAPOR IMAGERY INDICATING DRY AND STABLE CONDITIONS OVER MUCH OF THE BASIN. AT THE LOWER LEVELS...SSMI TPW IMAGERY INDICATE MODERATE MOISTURE ACROSS HISPANIOLA AND EASTERN CUBA AND HIGH MOISTURE CONTENT OVER THE SW CARIBBEAN. THIS MOISTURE IS SUPPORTING CLOUDINESS OVER HISPANIOLA AND ADJACENT WATERS WITH ISOLATED SHOWERS/TSTMS. OTHERWISE...A SLIGHT TIGHTER PRESSURE GRADIENT ACROSS THE CENTRAL BASIN SUPPORTS WINDS OF 20- 25 KT WHILE A MORE RELAXED GRADIENT ACROSS THE REMAINDER BASIN SUPPORTS WINDS OF 10-15 KT. ACROSS THE SW CARIBBEAN...A CLUSTER OF MODERATE CONVECTION WITH TSTMS IS OCCURRING S OF 11N W OF 81W...PRECIPITATION LIKELY ENHANCED DUE TO CLOSE PROXIMITY OF THE MONSOON TROUGH AXIS. NO MAJOR CHANGES ARE EXPECTED WITHIN THE NEXT 48 HOURS. ...HISPANIOLA... WHILE MIDDLE TO UPPER LEVEL DRY STABLE AIR REMAINS OVER THE ISLAND HINDERING DEEP CONVECTION...LOW LEVEL MOISTURE SUPPORT SHALLOW CLOUDS EXTENDING TO SURROUNDING COASTAL WATERS WITH ISOLATED SHOWERS AND TSTMS. FAIR WEATHER IS EXPECTED TO DOMINATE THROUGH THE REST OF THE DAY. ATLANTIC OCEAN... MIDDLE TO UPPER LEVEL RIDGING CONTINUES TO SUPPORT A WEAK SURFACE RIDGING ACROSS THE SW N ATLC ANCHORED BY A 1017 MB HIGH NEAR 28N71W. THIS HIGH IS EXPECTED TO SLIDE GRADUALLY NE DURING THE NEXT 24 HOURS. OVER THE NW ATLC WATERS...A MIDDLE TO UPPER LEVEL LOW CENTERED NEAR 41N61W SUPPORTS A DISSIPATING COLD FRONT ANALYZED FROM 30N59W SW TO 27N67W. FARTHER EAST...A WEAK SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY SUPPORTING A SURFACE TROUGH FROM 30N39W SW TO 24N46W TO 22N54W. ISOLATED SHOWERS ARE OCCURRING WITHIN 90 NM EITHER SIDE OF THE BOUNDARY. OTHERWISE...THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1023 MB HIGH CENTERED NORTH OF THE MADEIRA ISLANDS NEAR 37N16W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR