000 AXNT20 KNHC 082351 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE SEP 08 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 DEPRESSION GRACE IS CENTERED NEAR 14.4N 44.2W AT 08/2100 UTC OR ABOUT 995 NM E OF THE LESSER ANTILLES MOVING W AT 16 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. A NEW BURST OF DEEP CONVECTION HAS OCCURRED OVER THE S SEMICIRCLE BUT LACKS BANDING FEATURE. SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 150 NM OVER THE SW QUADRANT. PLEASE SEE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS. A BROAD AREA OF LOW PRESSURE IS LOCATED AT ABOUT 195 NM E-SE OF BERMUDA WITH A 1013 MB LOW ANALYZED ALONG A STATIONARY FRONTAL BOUNDARY NEAR 31N62W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION COVERS THE AREA FROM 31N-33N BETWEEN 58W-61W. THIS SYSTEM HAS BECOME BETTER ORGANIZED THIS EVENING AND THE ASSOCIATED CONVECTION MORE CONCENTRATED. UPPER LEVEL WINDS HAVE ALSO BECOME MORE FAVORABLE. THERE IS A MEDIUM CHANCE OF A SUBTROPICAL OR TROPICAL FORMATION OVER THE NEXT 48 HOURS AS THE LOW REMAINS NEARLY STATIONARY TONIGHT THEN MOVES N 5-10 KT ON WED AND THU. ...TROPICAL WAVES... TROPICAL WAVE JUST W OF THE CAPE VERDE ISLANDS IS ALONG 27W FROM 9N-20N MOVING W NEAR 15 KT OVER PAST 24 HOURS. SSMI TPW INDICATES THE WAVE IS ALONG THE LEADING EDGE OF A HIGH AMPLITUDE SURGE OF DEEP MOISTURE. NO ASSOCIATED DEEP CONVECTION. TROPICAL WAVE IN THE W TROPICAL ATLC EXTENDS ALONG 54W FROM 7N- 15N MOVING W NEAR 20 KT OVER THE PAST 24 HOURS. SSMI TPW INDICATES THE WAVE IS EMBEDDED WITHIN A SURGE OF DEEP MOISTURE. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 10N-13N BETWEEN 53W-57W WITH SCATTERED MODERATE CONVECTION FROM 8N-10N BETWEEN 52W-54W. TROPICAL WAVE IN THE E CARIBBEAN EXTENDS ALONG 66W/67W FROM 16N TO THE COAST OF SOUTH AMERICA MOVING W NEAR 20 KT OVER THE PAST 24 HOURS. SSMI TPW INDICATED THE WAVE IS EMBEDDED WITHIN A LOW AMPLITUDE SURGE OF DEEP MOISTURE. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 13N TO THE COAST OF VENEZUELA BETWEEN 67W-70W. TROPICAL WAVE IN THE W CARIBBEAN IS ALONG 82W FROM 10N-20N MOVING W NEAR 15 KT OVER PAST 24 HOURS. SSMI TPW INDICATES THE WAVE IS EMBEDDED WITHIN A WEAK SURGE OF DEEP MOISTURE. NO ASSOCIATED DEEP CONVECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM OVER AFRICA INTO THE E TROPICAL ATLC NEAR 20N16W ALONG 12N24W TO 13N36W. THE ITCZ HAS BEEN DISRUPTED BY T.D. GRACE. ANY DEEP CONVECTION IS ASSOCIATED WITH THE W TROPICAL ATLC TROPICAL WAVE AND T.D. GRACE. ...DISCUSSION... GULF OF MEXICO... AN ELONGATED UPPER LOW IS OVER THE NW GULF NEAR 27N91W WITH A TROUGH AXIS EXTENDING N OVER BILOXI MISSISSIPPI AND S TO OVER THE CENTRAL BAY OF CAMPECHE. THIS UPPER TROUGH DOMINATES THE GULF THIS EVENING. THE UPPER LOW IS GENERATING SCATTERED TO NUMEROUS SHOWERS/ISOLATED THUNDERSTORMS FROM 23N-28N BETWEEN 86W- 95W WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS S OF 24N BETWEEN 82W-92W. THE 1013 MB LOW THAT HAD BEEN IN THE NE GULF HAS MOVED INLAND AND AT 08/2100 UTC IS OVER SW GEORGIA. A SURFACE HIGH WILL FORM NEAR 28N84W ON WED NIGHT. CARIBBEAN SEA... AN UPPER RIDGE COVERS THE CARIBBEAN W OF 76W AND IS ANCHORED IN THE SW CARIBBEAN NEAR 11N80W. A SECOND UPPER RIDGE IS ANCHORED IN THE W TROPICAL ATLC COVERING THE E CARIBBEAN E OF 68W. A INVERTED SURFACE TROUGH IS BETWEEN THESE UPPER RIDGES EXTENDING FROM THE GULF OF VENEZUELA TO HISPANIOLA. AFTERNOON THUNDERSTORMS HAVE DEVELOPED INLAND OVER CUBA AND JAMAICA. THE MONSOON TROUGH EXTENDS ACROSS PANAMA GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 10N BETWEEN 78W-82W. THIS IS LEAVING THE REMAINDER OF THE CARIBBEAN WITH MOSTLY CLEAR SKIES THIS EVENING. FRESH TO STRONG TRADE WINDS WILL PULSE IN THE S/CENTRAL CARIBBEAN THROUGH WED. W CARIBBEAN TROPICAL WAVE WILL MOVE THROUGH THE SW CARIBBEAN TODAY AND THROUGH THE GULF OF HONDURAS TONIGHT INTO WED. E CARIBBEAN TROPICAL WAVE MOVE INTO THE CENTRAL CARIBBEAN TONIGHT AND WED. ...HISPANIOLA... AFTERNOON SHOWERS HAVE DEVELOPED OVER PORTIONS OF THE ISLAND. DAYTIME HEATING COUPLED WITH OROGRAPHIC LIFTING COULD PRODUCE ISOLATED SHOWERS IN THE AFTERNOON/EVENING HOURS THROUGH WED. ATLANTIC OCEAN... AN UPPER RIDGE OVER THE W CARIBBEAN EXTENDS ACROSS CENTRAL CUBA OVER THE W ATLC TO BEYOND 32N77W AND IS PROVIDING DIFFLUNCE ALOFT TO GENERATE SCATTERED TO NUMEROUS SHOWERS/ISOLATED THUNDERSTORMS WITHIN 60 NM ALONG THE COAST OF FLORIDA FROM 27N- 32N. AN UPPER TROUGH EXTENDS OVER THE CENTRAL ATLC SUPPORTING A STATIONARY FRONT THAT MEANDERS THROUGH 32N36W ALONG 30N44W 27N51W 31N59W THROUGH A 1013 MB LOW...IN THE SPECIAL FEATURES ABOVE...THEN ALONG 29N64W TO BEYOND 32N70W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 120 NM S OF THE FRONT BETWEEN 46W-49W. SEE SPECIAL FEATURES ABOVE FOR OTHER CONVECTION. A 1018 MB HIGH IS LOCATED OVER THE W ATLC NEAR 27N72W. A WEAK SURFACE RIDGE COVERS THE E ATLC S OF THE STATIONARY FRONT WITH A 1019 MB HIGH ABOUT 130 NM N-NE OF MADIERA ISLANDS AND A SECOND 1019 MB HIGH NEAR 28N31W. A STRONGER SURFACE RIDGE IS N OF THE FRONT. THE WEAK W ATLC SURFACE RIDGE WILL BE REPLACED BY STRONGER HIGH PRESSURE ON WED. THE 1013 MB LOW IN THE SPECIAL FEATURES WILL REMAIN NEARLY STATIONARY THROUGH WED AFTERNOON. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW