000 AXNT20 KNHC 040000 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN MAY 03 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 2345 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 07N12W TO 03N16W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 03N16W TO 02N33W TO THE NORTHERN COAST OF BRAZIL NEAR 01S50W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 03S TO 11N E OF 20W. SCATTERED MODERATE CONVECTION IS FROM 06S TO 05N W OF 20W. ...DISCUSSION... GULF OF MEXICO... A SURFACE RIDGE EXTENDS FROM NOVA SCOTIA SW ALONG THE SE CONUS INTO THE GULF WITH A 1023 MB HIGH CENTERED OVER NORTH CAROLINA ADJACENT WATERS NEAR 32N75W. AN UPPER LEVEL TROUGH EXTENDING FROM WEST VIRGINIA SOUTHWARD ACROSS THE EASTERN GULF TO A BASE OVER THE NW CARIBBEAN SUPPORT A WEAKNESS IN THE SURFACE RIDGE ANALYZED AS A SURFACE TROUGH FROM 29N86W TO 23N84W. LOW-LEVEL MOISTURE CONVERGENCE NEAR THE TAIL OF THE TROUGH AND FORCING BY THE UPPER TROUGH SUPPORT SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS FROM 23N TO 26N BETWEEN 83W AND 86W. SURFACE HIGH PRESSURE ALONG WITH DEEP LAYER DRY AIR AS DEPICTED BY WATER VAPOR AND SSMI TPW IMAGERY SUPPORT FAIR WEATHER ELSEWHERE. WINDS ACROSS THE BASIN ARE MAINLY FROM THE E-SE IN THE RANGE OF 10 TO 15 KT...EXCEPT SE OF THE TROUGH AXIS AND THE FLORIDA STRAITS WHERE WINDS CAN REACH A MAXIMUM OF 20 KT. SURFACE RIDGING WILL BE THE DOMINANT FEATURE OVER THE BASIN DURING THE NEXT TWO DAYS. THE SURFACE TROUGH WILL MOVE OVER WESTERN GULF WATERS MONDAY WHERE IT IS EXPECTED TO DISSIPATE. LOW PRESSURE STARTS TO BUILD OVER THE WESTERN BASIN TUESDAY MORNING. CARIBBEAN SEA... AN UPPER LEVEL TROUGH OVER THE NW ATLC WATERS CONTINUE TO SUPPORT A LOW PRESSURE SYSTEM FROM WHICH A STATIONARY FRONT EXTENDS FROM 31N54W SW TO 25N64W TO EASTERN CUBA NEAR 20N74W INTO THE NW CARIBBEAN WHERE IT STARTS TO DISSIPATE. THE BASE OF AN UPPER LEVEL TROUGH EXTENDING SOUTHWARD FROM WEST VIRGINIA AND AN UPPER RIDGE ANCHORED OVER THE CENTRAL ATLC ARE GENERATING DIFFLUENT FLOW ACROSS THE NW CARIBBEAN...WHICH ALONG WITH ABUNDANT LOW LEVEL MOISTURE SUPPORT SCATTERED SHOWERS AND TSTMS N OF 18N BETWEEN 75W AND 85W. ISOLATED SHOWERS ARE ELSEWHERE S OF 18N BETWEEN 81W AND 84W. SHALLOW MOISTURE IS ENTERING THE FAR EASTERN BASIN...THUS ENHANCING ISOLATED SHOWERS ACROSS THE LESSER ANTILLES AND OVER EASTERN PUERTO RICO ADJACENT WATERS. AN ACTIVE MONSOON TROUGH OVER THE EAST PACIFIC WATERS IS ENHANCING SHOWERS OVER THE SW BASIN S OF 12N BETWEEN 79W AND 83W. THE REMAINDER BASIN IS UNDER THE INFLUENCE OF THE UPPER LEVEL RIDGE AND DEEP LAYER DRY AIR THAT SUPPORT FAIR WEATHER. TRADES OF 10 TO 15 KT ARE EAST OF THE DISSIPATING STATIONARY FRONT...INCREASING TO 20 KT ALONG THE COAST OF NORTHERN SOUTH AMERICA. NORTHERLY WIND OF 10 KT DOMINATE OVER THE NW BASIN WEST OF THE DISSIPATING BOUNDARY. THE DISSIPATING STATIONARY FRONT WILL CONTINUE TO WEAKEN...LEAVING A SURFACE TROUGH THAT WILL DRIFT WESTWARD TOWARDS THE YUCATAN PENINSULA MONDAY MORNING. ...HISPANIOLA... LOW LEVEL MOISTURE ASSOCIATED WITH A STATIONARY FRONT EXTENDING FROM THE CENTRAL ATLC SW TO EASTERN CUBA AND THEN DISSIPATING OVER THE NW CARIBBEAN SUPPORTS CLOUDINESS ACROSS HAITI AND WESTERN DOMINICAN REPUBLIC. LOW LEVEL MOISTURE CONVERGENCE ASSOCIATED WITH THE FRONT ALONG WITH A DIFFLUENT ENVIRONMENT ALOFT MAY ENHANCE ISOLATED SHOWERS TONIGHT ACROSS THE WINDWARD PASSAGE AND THE REGIONS AFOREMENTIONED. THE PORTION OF THE FRONT OVER THE CARIBBEAN WILL CONTINUE TO WEAKEN LEAVING A SURFACE TROUGH TO MOVE OVER THE YUCATAN PENINSULA TUESDAY MORNING. THE PORTION OF THE FRONT N OF EASTERN CUBA WILL START TO DISSIPATE MONDAY MORNING. LINGERING MOISTURE ASSOCIATED WITH THIS BOUNDARY MAY ENHANCE SHOWERS ACROSS THE WESTERN ISLAND AND ADJACENT WATERS THROUGH MONDAY EVENING. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH OVER THE NW ATLC WATERS CONTINUE TO SUPPORT A LOW PRESSURE SYSTEM FROM WHICH A STATIONARY FRONT EXTENDS FROM 31N54W SW TO 25N64W TO EASTERN CUBA NEAR 20N74W INTO THE NW CARIBBEAN WHERE IT STARTS TO DISSIPATE. THE BASE OF AN UPPER LEVEL TROUGH EXTENDING SOUTHWARD FROM WEST VIRGINIA INTO THE NW CARIBBEAN AND AN UPPER RIDGE ANCHORED OVER THE CENTRAL ATLC ARE GENERATING DIFFLUENT FLOW ACROSS PORTIONS OF THE SW N ATLC...WHICH ALONG WITH ABUNDANT LOW LEVEL MOISTURE SUPPORT SCATTERED SHOWERS WITHIN 360 NM W OF THE FRONT...INCLUDING THE CENTRAL AND SOUTHERN BAHAMAS. A SURFACE LOW PRESSURE SYSTEM IS E OF THE CANARY ISLANDS FROM WHICH A COLD FRONT EXTENDS ENTERING THE CENTRAL ATLC WATERS ALONG 30N27W TO 28N35W TO 29N39W WITH NO CONVECTION ASSOCIATED WITH IT. THE REMAINDER BASIN IS UNDER THE INFLUENCE OF A SURFACE RIDGE BEING ANCHORED BY A 1021 MB HIGH NEAR 25N49W. THE FRONT WILL DISSIPATE OVER THE NW CARIBBEAN AND WILL START TO WEAKEN OVER THE SW N ATLC BY MONDAY MORNING...LEAVING AN ELONGATED AREA OF LOW PRESSURE OVER THE NORTHERN BAHAMAS BY TUESDAY MORNING. RIDGING WILL DOMINATE ELSEWHERE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR