000 AXNT20 KNHC 231049 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI MAY 23 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. ...TROPICAL WAVES... A TROPICAL WAVE IS NOTED OFF THE COAST OF WEST AFRICA ALONG 19W FROM 04N TO 10N. THE WAVE HAS A WELL DEFINED LOWER TO MID LEVEL CIRCULATION CENTERED NEAR 06N19W. THE WAVE IS REPRESENTED POORLY OVER THE WAVE INDICATED VERY LIGHT SURFACE WINDS WITH NO DISCERNIBLE CYCLONIC TURNING IN A RECENT ASCAT SATELLITE PASS. THE SURFACE WIND PATTERN SUGGESTS THAT THE WAVE IS LOCATED JUST TO THE EAST OF WELL DEFINED CONFLUENT FLOW THAT FORMS THE START OF THE ITCZ EXTENDING FARTHER TO THE WEST. A BROAD AREA OF SHOWERS AND THUNDERSTORMS ARE NOTED ACCORDINGLY JUST TO THE WEST OF THE WAVE AXIS. THE WAVE IS RELATED TO ANOTHER CIRCULATION FARTHER NORTH THAT MOVED OFF THE COAST OF SENEGAL A COUPLE OF DAYS AGO BUT HAS SINCE WEAKENED. LOOKING AHEAD...GFS OUTPUT SHOWS THE WAVE AT H7 AS FAIRLY LOW AMPLITUDE AND LOW LATITUDE INTO SUNDAY AS IT DRIFTS WESTWARD...BUT MAY AMPLIFY NEAR 40W BY LATE SUNDAY AS IT STARTS TO INTERACT WITH AN UPPER TROUGH N OF THE AREA. A SECOND TROPICAL WAVE IS OVER THE CENTRAL TROPICAL ATLC ALONG SHOWED SUBTLE CYCLONIC TURNING IN THIS AREA AT THE SURFACE...ENHANCING AN AREA OF 20 KT TRADES ON THE NORTH END OF THE WAVE. THE WAVE IS RIDING THE CUSP OF DEEP MOISTURE NOTED IN SSMI PRECIPITABLE WATER COMPOSITE IMAGERY. THE WAVE IS TO THE SW CORNER OF A BROAD MID/UPPER RIDGE EXTENDING ALONG ROUGHLY 10N AND TOWARD AN AREA OF MORE FAVORABLE UPPER FLOW BETWEEN THE RIDGE AND A BROAD MID LATITUDE MID/UPPER TROUGH TO THE NORTHEAST. THE WAVE WILL THUS AMPLIFY SLIGHT AND SLOW DOWN AS IT MOVES INTO NE SOUTH AMERICA AND THE FAR SOUTHERN WINDWARD ISLANDS THROUGH THE WEEKEND...FOLLOWED BY INCREASED TRADES. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH REACHES ACROSS WEST AFRICA ALONG 13N BUT IS INTERRUPTED BY THE TROPICAL WAVE BEFORE IT REACHES THE ATLANTIC COAST. THE ITCZ STARTS WEST OF THE TROPICAL WAVE AT 04N21W AND REACHES SW TO THE COAST OF BRAZIL NEAR 01S45W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS NOTED WITHIN 120 NM N AND 240 NM S OF THE ITCZ W OF 25W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL RIDGING REMAINS IN PLACE ACROSS THE WESTERN GULF ALONG 95W...TO THE WEST OF A BROAD TROUGH OVER THE SW NORTH ATLANTIC. AN ASSOCIATED 1020 MB SURFACE HIGH IS ANCHORED OVER THE NE GULF NEAR 28N87W...MAINTAINING GENERALLY LIGHT TO MODERATE FLOW ACROSS THE BASIN. THE ONLY EXCEPTION IS 15 TO 20 KT NE TO E WINDS RELATED TO THE TYPICAL OVERNIGHT TROUGH OFF THE WEST COAST OF THE YUCATAN PENINSULA. DEEP LAYER DRY AIR AND WIND SHEAR CONTINUE TO SUPPORT FAIR WEATHER AND CLEAR SKIES IN THE WHOLE REGION. NO SIGNIFICANT CHANGES TO THE CURRENT CONDITIONS ARE EXPECTED WITHIN THE NEXT 48 TO 72 HOURS. CARIBBEAN SEA... THE SOUTHERN STREAM JET REMAINS ACTIVE AT THE BASE OF A BROAD MIDDLE TO UPPER LEVEL TROUGH EXTENDING ACROSS THE CENTRAL CUBA AND THE NW CARIBBEAN. THIS IS ALLOWING SCATTERED MID AND UPPER CLOUDINESS ACROSS THE CENTRAL PORTION OF THE BASIN PARTICULARLY FROM NICARAGUA TO HISPANIOLA. RIDGING N OF THE AREA IS MAINTAINING FRESH TO STRONG TRADE WINDS ACROSS THE CENTRAL CARIBBEAN...PARTICULARLY OFF THE COAST OF NE COLOMBIA AND NW VENEZUELA. FRESH TRADE WINDS ARE ALSO FUNNELING ACROSS THE GULF OF HONDURAS. LITTLE CHANGE IS EXPECTED IN THE PATTERN THROUGH THE WEEKEND. ...HISPANIOLA... SHOWERS AND A FEW THUNDERSTORMS WILL PERSIST ACROSS HISPANIOLA FOR THE NEXT COUPLE OF DAYS...RELATED TO A MID TO UPPER TROUGH EXTENDING FROM CENTRAL CUBA AND THE NW CARIBBEAN. LITTLE CHANGE IS EXPECTED IN THE UPPER PATTERN...AND THE PERSISTENT MODERATE TO AT TIMES HEAVY PRECIPITATION OVER HIGHER TERRAIN COULD RESULT IN LOCALIZED FLOODING. WHILE WIDESPREAD HEAVY CONVECTION HAS NOT BEEN NOTICED...HISPANIOLA HAS BEEN IN THIS WET PATTERN FOR THE PAST SEVERAL DAYS. STRONGER CONVECTION IS LIKELY OVER THE N CENTRAL MOUNTAIN RANGE BY AFTERNOON. A WEAK SURFACE TROUGH REMAINS IN THE AREA. LOOKING AHEAD TO LATE IN THE WEEKEND...SLIGHTLY DRIER CONDITIONS ARE EXPECTED AS THE AXIS OF THE UPPER TROUGH SHIFT MORE TO THE EAST AND DRIER MID ATLC AIR ENCOMPASSES THE LOWER AND MID LEVELS. DESPITE LOWER SLIGHTLY LOWER MOISTURE...AFTERNOON CONVECTION MAY BE ENHANCED SLIGHTLY OVER THE MOUNTAINS EARLY IN THE WEEK AS WEAK DISTURBANCES WILL MOVE N OF THE AREA IN THE NW FLOW ALOFT. ATLANTIC OCEAN... RECENT ASCAT SATELLITE DATA SHOWED MODERATE TO FRESH SW FLOW NEAR AN AREA OF SHOWERS AND THUNDERSTORMS N OF 29N BETWEEN 70W AND 75W...AHEAD OF A SURFACE TROUGH OFF THE CAROLINA COAST. THE TROUGH...AND A WEAK COLD FRONT BEHIND IT...ARE ASSOCIATED WITH A SERIES OF MID/UPPER DISTURBANCES MOVING FROM THE TENNESSEE VALLEY THROUGH THE CAROLINAS...AND TOWARD THE BASE OF A BROAD MID/UPPER TROUGH EXTENDING ALONG ROUGHLY 75W. THE UPPER TROUGH WILL BECOME MORE AMPLIFIED THROUGH THE WEEKEND AND SHIFT EASTWARD SLIGHTLY AS THE WEAK DISTURBANCES MOVE THROUGH. THE ASSOCIATED COLD FRONT WILL SAG SOUTHWARD TO 25N THROUGH SAT THEN BECOME DIFFUSE. A FEW SHOWERS AND THUNDERSTORMS ARE NOTED TO THE SOUTHEAST OF THIS TROUGH N OF PUERTO RICO AND THE LEEWARD ISLANDS. FARTHER EAST...BROAD RIDGING WILL EXTEND ACROSS THE BASIN INTO THE N CENTRAL ATLANTIC. A PAIR OF TROPICAL WAVES WILL MIGRATE WESTWARD SOUTH OF THE RIDGE THROUGH THE WEEKEND...ENHANCING TRADE WIND FLOW W OF 40W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ CHRISTENSEN