000 AXNT20 KNHC 232355 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... TROPICAL STORM DANNY IS CENTERED NEAR 15.5N 59.3W AT 24/0000 UTC OR BOUT 120 NM E OF DOMINICA AND ABOUT 130 NM E-SE OF GUADELOUPE MOVING W AT 13 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1008 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 150 NM OF THE CENTER OVER THE NE QUADRANT. PLEASE SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. A BROAD AREA OF LOW PRESSURE ANALYZED AS A 1007 MB LOW IS CENTERED NEAR 14N36W. SSMI TPW SHOWS THE LOW IS EMBEDDED WITHIN AN AREA OF DEEP MOISTURE. CLUSTERS OF SCATTERED MODERATE/ ISOLATED STRONG CONVECTION ARE FROM 12N-15N BETWEEN 37W- 45W. ENVIRONMENTAL CONDITIONS ARE CONDUCIVE FOR ADDITIONAL DEVELOPMENT AND A TROPICAL DEPRESSION IS LIKELY TO FORM IN THE NEXT DAY OR TWO WHILE THE LOW MOVES QUICKLY W NEAR 25-20 KT. THERE IS A HIGH CHANCE OF TROPICAL FORMATION OVER THE NEXT 48 HOURS. ...TROPICAL WAVES... TROPICAL WAVE IN THE W TROPICAL ATLC EXTENDS ALONG 20W FROM 11N- 17N MOVING W NEAR 15 KT OVER THE PAST 12 HOURS. SSMI TPW INDICATES THE WAVE IS EMBEDDED WITHIN A SURGE OF DEEP MOISTURE THAT COVERS THE AREA E OF THE CAPE VERDE ISLANDS TO THE COAST OF AFRICA. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 15N TO 17N E OF 23W TO THE COAST OF W AFRICA. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 17N16W TO E OF THE TROPICAL WAVE NEAR 15N19W THEN RESUMES W OF THE WAVE NEAR 14N23W ALONG 15N32W THROUGH THE 1008 MB LOW CENTERED NEAR 14N37W TO 12N44W. THE ITCZ BEGINS TO THE S NEAR 10N45W ALONG 8N52W TO 11N61W. SCATTERED MODERATE/ ISOLATED STRONG CONVECTION IS FROM 14N-16N BETWEEN 24W-27W AND FROM 10N-12N BETWEEN 52W-54W. SCATTERED MODERATE CONVECTION IS FROM 9N-11N BETWEEN 22W-26W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LOW IS CENTERED OVER THE W GULF NEAR 23N97W COVERING THE AREA W OF 90W WHILE AN UPPER RIDGE IS ANCHORED IN THE W ATLC COVERS THE E GULF. THESE UPPER FEATURES ARE GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ACROSS THE GULF FROM 22N-27W BETWEEN 83W-96W. AFTERNOON THUNDERSTORMS HAVE DEVELOPED INLAND OVER S FLORIDA AND W CUBA THAT ARE MOVING INTO THE GULF WATERS. A SURFACE RIDGE EXTENDS FROM THE E CONUS OVER THE N GULF WITH A 1019 MB HIGH NEAR 29N93W. WEAK HIGH PRESSURE OVER THE NE GULF WILL SHIFT S EARLY MON NIGHT AS A WEAK TROUGH STALLS OVER THE NE GULF WHERE IT WILL MEANDER THROUGH MID WEEK. CARIBBEAN SEA... THE PRIMARY CONCERN THIS EVENING REMAINS TROPICAL STORM DANNY APPROACHING THE LEEWARD ISLANDS. SEE SPECIAL FEATURES ABOVE. AN UPPER RIDGE COVERS THE W CARIBBEAN W OF 80W ANCHORED NEAR NE NICARAGUA NEAR 14N83W. AN ELONGATED UPPER LOW IS CENTERED IN THE E CARIBBEAN NEAR 15N70W EXTENDING A TROUGH AXIS FROM THE CENTRAL ATLC ACROSS PUERTO RICO AND A SECOND TROUGH AXIS NW TO NEAR THE CAYMAN ISLANDS. AFTERNOON THUNDERSTORMS HAVE DEVELOPED INLAND OVER W PUERTO RICO...HISPANIOLA...JAMAICA...AND CUBA. THE MONSOON TROUGH EXTENDS ACROSS PANAMA AND COSTA RICA GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 10N BETWEEN 77W- 82W. THIS IS LEAVING THE REMAINDER OF THE CARIBBEAN UNDER MOSTLY CLEAR SKIES THIS EVENING. TROPICAL STORM DANNY WILL MOVE ACROSS THE LEEWARD ISLANDS LATE TONIGHT/EARLY MON WEAKENING TO TROPICAL DEPRESSION ON MON AND CONTINUE S OF PUERTO RICO TUE. ...HISPANIOLA... AFTERNOON THUNDERSTORMS HAVE DEVELOPED INLAND OVER THE ISLAND THIS EVENING MAINLY W OF 71W. TROPICAL STORM DANNY IS EXPECTED TO MOVE ACROSS THE LEEWARD ISLANDS LATE TONIGHT/EARLY MON WEAKENING TO TROPICAL DEPRESSION ON MON AND CONTINUE S OF PUERTO RICO TUE. THIS WILL INCREASE THE MOISTURE STARTING MON AFTERNOON AND SPREADING W THROUGH MID WEEK WHEN THE SYSTEM WILL ALONG THE S COAST OF HISPANIOLA. THIS WILL INCREASE SHOWERS AND POSSIBLE THUNDERSTORMS STARTING MON AFTERNOON THROUGH MID WEEK. ATLANTIC OCEAN... THE PRIMARY CONCERN THIS EVENING REMAINS TROPICAL STORM DANNY IN THE W TROPICAL ATLC APPROACHING THE LEEWARD ISLANDS. SEE SPECIAL FEATURES ABOVE. AN UPPER RIDGE IS ANCHORED IN THE W ATLC NEAR 27N77W COVERING THE AREA W OF 68W AND EXTENDS INTO THE GULF OF MEXICO. AN UPPER LOW IS CENTERED N OF THE AREA SUPPORTING A SURFACE LOW WELL N OF THE DISCUSSION AREA AND EXTENDING A SURFACE TROUGH INTO THE REGION NEAR 32N62W AND CONTINUES ALONG 28N64W TO 26N68W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 90 NM E AND 60 NM W OF THE SURFACE TROUGH. A SECOND UPPER LOW IS IN THE CENTRAL ATLC NEAR 32N44W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 27N BETWEEN 40W-47W. THE CENTRAL AND E ATLC ARE MOSTLY DOMINATE BY A SURFACE RIDGE THAT IS ANCHORED BY A 1026 MB HIGH ABOUT 500 NM W-SW OF THE AZORES. TROPICAL STORM DANNY WILL MOVE ACROSS THE LEEWARD ISLANDS LATE TONIGHT/EARLY MON WEAKENING TO TROPICAL DEPRESSION IN THE NE CARIBBEAN. THE CENTRAL ATLC SURFACE RIDGE WILL MEANDER ALONG 28N ON TUE THROUGH MID WEEK. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW