000 AXNT20 KNHC 102357 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU SEP 10 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 HENRI IS CENTERED NEAR 33.9N 60.7W AT 10/2100 UTC OR 225 NM E-NE OF BERMUDA AND ABOUT 840 NM S-SW OF CAPE RACE NEWFOUNDLAND MOVING N AT 13 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1008 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. TROPICAL STORM HENRI REMAINS POORLY ORGANIZED WITH SOME VERTICAL SHEAR THAT IS FORECASTED TO RELAX OVERNIGHT. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 60 NM OF LINE FROM 33N57W TO 36N60W. PLEASE SEE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IN THE W TROPICAL ATLC EXTENDS FROM 18N32W TO 8N35W MOVING W-SW 15-20 KT OVER PAST 24 HOURS. SSMI TPW INDICATES THE WAVE IS WITHIN A HIGH AMPLITUDE VERY BROAD SURGE OF DEEP MOISTURE. THERE IS NO ASSOCIATED DEEP CONVECTION WITH SCATTERED SHOWERS FROM 12N-15N BETWEEN 33W-38W. TROPICAL WAVE...REMNANTS OF GRACE...EXTENDS FROM 19N57W TO 12N59W MOVING W NEAR 20 KT OVER PAST 24 HOURS. SSMI TPW INDICATES THE WAVE IS WITHIN A HIGH AMPLITUDE SURGE OF DEEP MOISTURE. SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 75 NM OF LINE FROM 15N56W TO 18N60W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE OVER THE LESSER ANTILLES S OF GUADELOUPE FROM 58W-64W. TROPICAL WAVE IN THE CENTRAL CARIBBEAN IS ALONG 71W FROM 16N TO OVER SOUTH AMERICA MOVING W NEAR 25 KT OVER THE PAST 24 HOURS. SSMI TPW INDICATES THE WAVE IS EMBEDDED WITHIN A LOW AMPLITUDE SURGE OF DEEP MOISTURE. THERE IS NO ASSOCIATED DEEP CONVECTION WITH SCATTERED SHOWERS FROM 12N-15N BETWEEN 66W-70W. TROPICAL WAVE IN THE W CARIBBEAN IS ALONG 84W/85W FROM 17N TO OVER CENTRAL AMERICA MOVING W NEAR 25 KT OVER THE PAST 24 HOURS. SSMI TPW INDICATES THE WAVE IS EMBEDDED WITHIN A LOW AMPLITUDE SURGE OF MODERATE MOISTURE. THERE IS NO ASSOCIATED DEEP CONVECTION IN THE CARIBBEAN WATERS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM OVER AFRICA INTO THE E TROPICAL ATLC NEAR 12N16W ALONG 10N20W 12N26W TO E OF A TROPICAL WAVE NEAR 11N34W. THE ITCZ BEGINS W OF THE TROPICAL WAVE NEAR 10N37W ALONG 9N46W TO 14N56W. SCATTERED MODERATE TO STRONG CONVECTION IS INLAND AND WITHIN 45/60 NM ALONG THE COAST OF AFRICA FROM 10N-12N. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 6N-10N BETWEEN 15W-29W...FROM 6N-11N BETWEEN 37W-46W...AND WITHIN 90/120 NM S OF THE ITCZ BETWEEN 50W- 56W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER TROUGH DIPS S OVER THE N GULF SUPPORTING FRONTAL BOUNDARY THAT IS WELL INLAND OVER THE SE CONUS. SHOWERS/ THUNDERSTORMS ASSOCIATED WITH THIS FRONT ARE MOSTLY INLAND OVER GEORGIA TO TEXAS WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORM OVER THE GULF WATERS N OF 28N W OF 85W. AN UPPER RIDGE OVER W MEXICO IS PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED TO NUMEROUS SHOWERS/ISOLATED THUNDERSTORMS N OF 24N W OF 92W. A SECOND UPPER RIDGE EXTENDS FROM THE NW CARIBBEAN INTO THE W ATLC PROVIDING DIFFLUENCE ALOFT TO GENERATE ISOLATED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 24N-26N E OF 84W TO OVER S FLORIDA AND THE FLORIDA KEYS. A WEAK SURFACE RIDGE EXTENDS FROM THE W ATLC ACROSS CENTRAL FLORIDA TO OVER THE GULF WITH A 1016 MB HIGH NEAR 27N86W. THE ABOVE COLD FRONT WILL MOVE INTO THE N/CENTRAL GULF FRI NIGHT WITH A SECOND FRONT ENTERING THE AREA SAT NIGHT. CARIBBEAN SEA... AN UPPER RIDGE COVERS THE CARIBBEAN W OF 75W AND IS ANCHORED NEAR 18N85W EXTENDING A RIDGE AXIS ACROSS CENTRAL CUBA INTO THE W ATLC. A SECOND WEAKER UPPER RIDGE IS ANCHORED IN THE W TROPICAL ATLC COVERING THE E CARIBBEAN E OF 68W. A WEAK INVERTED SURFACE TROUGH IS BETWEEN THESE UPPER RIDGES EXTENDING FROM THE GUAJIRA PENINSULA OF COLOMBIA TO THE MONA PASSAGE. CLUSTERS OF AFTERNOON SHOWERS/THUNDERSTORMS HAVE DEVELOPED INLAND OVER PUERTO RICO...HISPANIOLA...CUBA...AND JAMAICA. THE MONSOON TROUGH EXTENDS FROM COLOMBIA NEAR 11N75W ALONG 10N80W ACROSS W PANAMA/COSTA RICA NEAR 9N83W WITH SCATTERED TO NUMEROUS SHOWERS/ISOLATED THUNDERSTORMS S OF LINE FROM NICARAGUA NEAR 13N84W TO PANAMA NEAR 9N78W. W CARIBBEAN TROPICAL WAVE WILL MOVE W OF THE AREA FRI. CENTRAL CARIBBEAN TROPICAL WAVE WILL MOVE INTO THE W CARIBBEAN FRI NIGHT THROUGH SAT. THE W TROPICAL ATLC TROPICAL WAVE...REMNANTS OF GRACE...WILL ENTER THE E CARIBBEAN TONIGHT AND INTO THE CENTRAL ATLC FRI NIGHT REACHING THE W CARIBBEAN SAT NIGHT. ...HISPANIOLA... AFTERNOON SHOWERS/THUNDERSTORMS HAVE DEVELOPED OVER THE DOMINICAN REPUBLIC AND ARE MOVING INTO HAITI. DAYTIME HEATING COUPLED WITH OROGRAPHIC LIFTING COULD PRODUCE ISOLATED SHOWERS IN THE AFTERNOON/EVENING HOURS THROUGH FRI. MOISTURE AND POSSIBLE SHOWERS/THUNDERSTORMS ASSOCIATED WITH THE TROPICAL WAVE...REMNANTS OF GRACE...IS CURRENTLY E OF THE LESSER ANTILLES AND WILL APPROACH THE ISLAND FRI NIGHT SPREADING OVER THE ISLAND SAT. ATLANTIC OCEAN... AN UPPER RIDGE OVER THE NW CARIBBEAN EXTENDS ACROSS CENTRAL CUBA AND INTO THE W ATLC ALONG 23N79W TO BEYOND 32N75W. A WEAK SURFACE RIDGE COVERS THE W ATLC WITH A 1017 MB HIGH NEAR 26N74W THEN EXTENDS A RIDGE AXIS W OVER CENTRAL FLORIDA INTO THE GULF OF MEXICO. AN UPPER TROUGH IS TO THE E OF THE ABOVE FEATURES EXTENDING ACROSS BERMUDA TO THE MONA PASSAGE AND IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 23N-27N BETWEEN 61W-71W. AN UPPER LOW IS IN THE CENTRAL ATLC NEAR 28N45W GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 300 NM OF LINE FROM 26N51W TO BEYOND 32N55W. A SURFACE RIDGE COVERS THE REMAINDER OF THE ATLC E OF 55W ANCHORED BY A 1023 MB HIGH N OF THE DISCUSSION AREA. A WEAK SURFACE TROUGH DIVIDES THE ABOVE SURFACE RIDGE EXTENDING FROM 32N28W 31N32W THROUGH A WEAK 1017 MB LOW NEAR 28N35W ALONG 27N38W TO 27N46W. S OF THE SURFACE TROUGH IS A 1019 MB HIGH IN THE E ATLC NEAR 29N26W AND A 1018 MB HIGH IN THE CENTRAL ATLC NEAR 25N45W. THE W ATLC SURFACE RIDGE WILL SHIFT SLOWLY E TONIGHT THEN LOSE IDENTITY EARLY FRI ALONG A RIDGE BUILDING W NEAR 27N AND SHIFT TO THE E OF THE BAHAMAS ON SAT NIGHT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW