000 AXNT20 KNHC 240008 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI SEP 23 2011 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 OPHELIA IS CENTERED NEAR 15.5N 53.8W AT 23/2100 UTC OR ABOUT 540 MI...870 KM E OF THE LEEWARD ISLANDS MOVING WNW AT 13 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1001 MB. MAXIMUM SUSTAINED WIND SPEED IS 50 KT WITH GUSTS TO 60 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. TROPICAL-STORM-FORCE WINDS EXTEND OUTWARD UP TO 260 MILES...415 KM...MAINLY NORTH AND EAST OF THE CENTER. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 13N-20N BETWEEN 48W-54W. A 1009 MB LOW IS S OF THE CAPE VERDE ISLANDS NEAR 10N22W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 10N-12N BETWEEN 21W-25W. ENVIRONMENTAL CONDITIONS ARE CURRENTLY CONDUCIVE FOR ADDITIONAL DEVELOPMENT...AND THE LOW HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ...TROPICAL WAVES... TROPICAL WAVE IS ANALYZED FROM 19N34W TO 13N37 TO 6N37W MOVING W AT 10 KT. VISIBLE SATELLITE IMAGERY AND LOW-LEVEL STREAMLINE ANALYSIS INDICATES BROAD CYCLONIC FLOW IN THE VICINITY OF THE WAVE AXIS. TOTAL PRECIPITABLE WATER IMAGERY INDICATES THAT ENHANCED DEEP LAYER MOISTURE ACCOMPANIES THE WAVE. NO SIGNIFICANT DEEP CONVECTION IS NOTED WITH THE WAVE. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 13N17W TO THE LOW PRESSURE NOTED ABOVE NEAR 10N22W TO 8N32W. IN ADDITION TO THE CONVECTION MENTIONED WITH THE LOW...WIDELY SCATTERED MODERATE CONVECTION IS FROM 5N-8N BETWEEN 22W-32W. ...DISCUSSION... GULF OF MEXICO... THE TAIL END OF A COLD FRONT IS OVER THE GULF OF MEXICO FROM THE FLORIDA PANHANDLE AT 30N87W TO THE NW GULF AT 25N95W. SCATTERED SHOWERS ARE FROM 28N-31N BETWEEN 86W-89W. A SURFACE TROUGH EXTENDS FROM THE E GULF AT 27N84W TO THE YUCATAN PENINSULA AT 19N89W. SCATTERED MODERATE CONVECTION IS FROM 23N-27N BETWEEN 84W-86W...WHILE SCATTERED MODERATE TO STRONG CONVECTION IS INLAND OVER THE YUCATAN PENINSULA N OF 17N. AIRMASS RAIN AND THUNDERSTORMS ARE INLAND OVER FLORIDA E OF 81W FROM JACKSONVILLE TO MIAMI. IN THE UPPER LEVELS...AN UPPER LEVEL TROUGH IS SUPPORTING THE SURFACE FRONT AND TROUGH HOWEVER STRONG SUBSIDENCE IS SUPPRESSING OVERALL CONVECTION. MOST OF THE W GULF HAS FAIR WEATHER. EXPECT...THE FRONT TO DRIFT OVER N FLORIDA IN 24 HOURS WITH CONTINUED CONVECTION OVER THE E GULF AND FLORIDA. CARIBBEAN SEA... A SURFACE TROUGH IS OVER THE YUCATAN PENINSULA. SEE ABOVE. A MONSOON TROUGH EXTENDS FROM N COLOMBIA TO COSTA RICA. SCATTERED MODERATE TO STRONG CONVECTION IS OVER PANAMA AND THE SW CARIBBEAN FROM 7N-11N BETWEEN 78W-83W. 10-20 KT TRADEWINDS ARE OVER THE CARIBBEAN SEA WITH STRONGEST WINDS ALONG THE COAST OF N COLOMBIA. SCATTERED MODERATE CONVECTION IS OVER THE HIGHER ELEVATIONS OF HISPANIOLA...JAMAICA...AND CUBA. WIDELY SCATTERED MODERATE CONVECTION IS ALSO OVER THE CENTRAL CARIBBEAN S OF JAMAICA FROM 13N-17N BETWEEN 72W-83W. EXPECT THE WESTERN EXTENT OF THE CONVECTIVE BANDING FROM OPHELIA TO BE OVER THE E CARIBBEAN WITHIN 24 HOURS. ALSO EXPECT CONTINUED CONVECTION OVER THE W CARIBBEAN AND CENTRAL AMERICA W OF 80W OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... A SURFACE TROUGH IS OVER THE BAHAMAS ALONG 28N78W 23N79W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 23N-28N BETWEEN 72W-78W. A 1027 MB HIGH IS OVER THE W ATLANTIC NEAR 35N60W. ANOTHER 1021 MB HIGH IS OVER THE E ATLANTIC NEAR 32N26W. SURFACE RIDGING WITH MOSTLY FAIR WEATHER IS OVER THE ATLANTIC FROM 20N-32N BETWEEN 20W-70W. EXPECT CONTINUED CONVECTION OVER THE BAHAMAS OVER THE NEXT 24 HOURS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA