000 AXNT20 KNHC 231201 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN AUG 23 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...SPECIAL FEATURES... TROPICAL STORM DANNY IS CENTERED NEAR 15.7N 56.7W AT 23/1200 UTC OR ABOUT 300 NM ESE OF ANTIGUA MOVING W AT 13 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1003 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. SCATTERED MODERATE CONVECTION IS OCCURRING FROM 16N-18N BETWEEN 53W-57W. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT4/WTNT34 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. TROPICAL WAVE EXTENDS FROM 12N33W TO 19N33W MOVING W AT 20-25 KT. THE WAVE COINCIDES WITH A RELATIVELY BROAD LOW-LEVEL MONSOONAL GYRE FOCUSED ON A 1009 MB LOW CENTERED ALONG THE MONSOON TROUGH AND WAVE AXIS NEAR 14N33W. THE GYRE AND ASSOCIATED WAVE ENERGY IS EXPECTED TO MOVE WESTWARD INTO THE CENTRAL TROPICAL ATLC THROUGH EARLY TUESDAY. SCATTERED MODERATE CONVECTION IS FROM 12N-16N BETWEEN 31W-37W. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 10N85W TO 15N86W MOVING W AT 15 KT. THE WAVE IS NOTED BENEATH MIDDLE TO UPPER LEVEL DIFFLUENCE ON THE SOUTHWESTERN PERIPHERY OF AN UPPER LEVEL ANTICYCLONE NOTED ON WATER VAPOR IMAGERY NEAR 14N82W. AS A RESULT...WIDELY SCATTERED MODERATE CONVECTION IS FROM 07N-14N BETWEEN 81W-86W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM THE AFRICAN COAST NEAR 13N17W INTO A 1009 MB LOW CENTERED NEAR 14N33W TO 13N39W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 07N37W TO 06N47W TO 08N51W. ASIDE FROM CONVECTION ASSOCIATED WITH THE TROPICAL WAVE ALONG 33W...SCATTERED MODERATE CONVECTION IS FROM 06N-09N BETWEEN 14W-26W...AND FROM 05N-08N BETWEEN 44W-50W. ISOLATED MODERATE CONVECTION IS FROM 11N-15N BETWEEN 17W-22W. ...DISCUSSION... GULF OF MEXICO... GENERALLY SOUTHEASTERLY FLOW ALOFT INFLUENCES MUCH OF THE GULF BASIN BETWEEN AN UPPER LEVEL RIDGE ANCHORED OVER THE SW NORTH ATLC NEAR 28N77W AND AN UPPER LEVEL LOW CENTERED OVER THE SW GULF NEAR 21N95W. ISOLATED SHOWERS AND TSTMS ARE OCCURRING ACROSS CENTRAL PORTIONS OF THE GULF FOCUSED FROM 22N-26N BETWEEN 88W-93W...WITH SIMILAR ACTIVITY OCCURRING FROM 24N-27N BETWEEN 82W-86W. LIGHT AND VARIABLE ANTICYCLONIC WINDS PERSIST ACROSS THE NE HALF OF THE GULF DUE TO A 1016 MB HIGH CENTERED NEAR 28N88W...WITH MODERATE S-SE RETURN FLOW NOTED ACROSS THE SW HALF OF THE GULF ON THE SOUTHWESTERN PERIPHERY OF THE HIGH. THE HIGH IS FORECAST TO SLOWLY DRIFT WESTWARD THROUGH MONDAY. CARIBBEAN SEA... AN UPPER LEVEL ANTICYCLONE IS CENTERED OVER THE SW CARIBBEAN NEAR 14N82W...WHILE A WEAK AND BROAD UPPER LEVEL LOW IS CENTERED OVER THE CENTRAL CARIBBEAN NEAR 16N68W. BOTH FEATURES REMAIN EMBEDDED WITHIN RELATIVELY DRY AIR AND OVERALL STABLE CONDITIONS ACROSS THE BASIN THIS MORNING. SCATTERED SHOWERS AND TSTMS ARE OCCURRING IN ASSOCIATION WITH A TROPICAL WAVE ALONG 86W S OF 14N W OF 81W...INCLUDING INLAND PORTIONS OF PANAMA...COSTA RICA... AND NICARAGUA. OTHERWISE...A FEW ISOLATED SHOWERS AND TSTMS CONTINUE ACROSS THE ADJACENT COASTAL WATERS OF CUBA. MAINLY MODERATE TO LOCALLY FRESH TRADES WILL PREVAIL ACROSS THE BASIN THROUGH LATE SUNDAY WITH THE EXCEPTION OF APPROACHING TROPICAL STORM DANNY ACROSS THE NE CARIBBEAN. ...HISPANIOLA... CURRENTLY...SKIES HAVE CLEARED SOMEWHAT FROM LINGERING OVERNIGHT ISOLATED SHOWERS AND TSTMS. CLEAR SKIES LIE TO THE EAST... HOWEVER SIMILAR DEVELOPMENT OF LATE AFTERNOON AND EARLY EVENING ISOLATED SHOWERS AND TSTMS IS POSSIBLE SUNDAY WITH LITTLE CHANGE IN OVERALL SYNOPTIC CONDITIONS ANTICIPATED UNTIL LATE MONDAY WHEN TROPICAL STORM DANNY APPROACHES FROM THE E-SE. ATLANTIC OCEAN... AN UPPER LEVEL ANTICYCLONE IS CENTERED OVER THE SW NORTH ATLC NEAR 28N77W WITH AN UPPER LEVEL LOW CENTERED TO THE EAST NEAR 32N66W. GENERALLY NORTHERLY FLOW ALOFT PREVAILS PROVIDING AN OVERALL STABLE ENVIRONMENT W OF 70W...HOWEVER A FEW ISOLATED SHOWERS ARE OCCURRING IN THE VICINITY OF A WEAK 1012 MB LOW CENTERED NEAR 25N70W AND ASSOCIATED SURFACE TROUGHING EXTENDING FROM THE LOW NE TO 29N63W. LOW-LEVEL MOISTURE CONVERGENCE NEAR THE SURFACE TROUGH AND MIDDLE TO UPPER LEVEL DIFFLUENCE IN ASSOCIATION WITH THE UPPER LEVEL LOW IS GENERATING WIDELY SCATTERED SHOWERS WITHIN 150 NM SE OF THE BOUNDARY...AND FROM 28N-33N BETWEEN 59W-64W. FARTHER EAST...ANOTHER UPPER LEVEL LOW IS CENTERED NEAR 31N47W THAT SUPPORTS AN AREA OF SCATTERED SHOWERS AND ISOLATED TSTMS FROM 26N-34N BETWEEN 42W-50W. ELSEWHERE...THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1028 MB HIGH CENTERED SW OF THE AZORES NEAR 35N35W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN