000 AXNT20 KNHC 172337 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON SEP 17 2012 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 NADINE IS CENTERED NEAR 33.5N 34.5W AT 17/2100 UTC OR ABOUT 525 MI...840 KM SW OF THE AZORES MOVING NE AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 987 MB. MAXIMUM SUSTAINED WIND SPEED IS 55 KT WITH GUSTS TO 65 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS N OF THE CENTER FROM 33N-36N BETWEEN 33W-36W. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 16N35W TO 10N40W MOVING W AT 10-15 KT. THIS WAVE IS WITHIN A SURGE OF DEEP LAYER MOISTURE AS SEEN ON SSMI TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED SHOWERS ARE WITHIN 90 NM OF THE WAVE AXIS. TROPICAL WAVE OVER THE LESSER ANTILLES EXTENDS FROM 18N58W TO 10N62W TO 10N59W MOVING W AT 5-10 KT. SCATTERED MODERATE CONVECTION IS WELL W OF THE WAVE AXIS FROM 15N-19N BETWEEN 63W-68W TO INCLUDE PUERTO RICO. SCATTERED SHOWERS ARE ELSEWHERE FROM 13N-19N BETWEEN 60W-69W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE COAST OF GUINEA AT 10N14W TO 7N20W TO 8N30W. AN ITCZ CONTINUES FROM 8N30W TO 11N36W. A SHORT ITCZ IS ALSO BETWEEN TROPICAL WAVES FROM 9N43W TO 7N50W TO 10N59W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 3N-8N BETWEEN 15W-36W. SCATTERED MODERATE CONVECTION IS FROM 6N-11N BETWEEN 44W-49W. ...DISCUSSION... GULF OF MEXICO... AS OF 2100 UTC...A 1006 MB LOW IS CENTERED OVER S LOUISIANA AT 31N92W. A COLD FRONT EXTENDS S FROM THE LOW TO THE SW GULF OF MEXICO ALONG 27N91W 22N95W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS E OF THE FRONT OVER THE NE GULF N OF 25N BETWEEN 84W-89W. WIDELY SCATTERED MODERATE CONVECTION IS ALSO INLAND OVER FLORIDA BETWEEN 80W-84W. ELSEWHERE...SCATTERED MODERATE TO STRONG CONVECTION IS INLAND OVER CUBA...AND OVER THE YUCATAN PENINSULA N OF 19N. MOSTLY FAIR WEATHER IS OVER THE NW GULF. IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS CENTERED OVER E TEXAS NEAR 30N95W SUPPORTING THE SURFACE LOW AND FRONT. STRONG SUBSIDENCE IS OVER TEXAS AND N MEXICO W OF THE UPPER LEVEL LOW. EXPECT THE COLD FRONT TO EXTEND FROM N FLORIDA TO THE YUCATAN PENINSULA IN 24 HOURS WITH CONVECTION. CARIBBEAN SEA... A TROPICAL WAVE IS PRODUCING CONVECTION OVER THE LEEWARD ISLANDS. SEE ABOVE. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS OVER HISPANIOLA AND JAMAICA. SCATTERED MODERATE TO STRONG CONVECTION IS INLAND OVER CUBA...AND OVER THE YUCATAN PENINSULA N OF 19N. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS ALSO INLAND OVER NICARAGUA...HONDURAS...AND GUATEMALA. FURTHER S...WIDELY SCATTERED MODERATE CONVECTION IS OVER NW VENEZUELA...N COLOMBIA...PANAMA ...AND COSTA RICA FROM 4N-11N BETWEEN 68W-85W. 10-20 KT TRADEWINDS ARE OVER THE CARIBBEAN SEA WITH STRONGEST WINDS ALONG THE COAST OF N COLOMBIA. IN THE UPPER LEVELS... AND UPPER LEVEL HIGH IS OVER HONDURAS NEAR 15N87W. AN UPPER LEVEL LOW IS CENTERED OVER THE CENTRAL CARIBBEAN NEAR 16N76W INFLUENCING THE CONVECTION OVER HISPANIOLA JAMAICA...AND E CUBA. EXPECT OVER THE NEXT 24 HOURS FOR THE TROPICAL WAVE TO CONTINUE TO PRODUCE CONVECTION OVER THE E CARIBBEAN. ALSO EXPECT CONTINUED CONVECTION OVER THE W CARIBBEAN AND CENTRAL AMERICA. ATLANTIC OCEAN... TROPICAL STORM NADINE IS OVER THE CENTRAL ATLANTIC. SEE THE SPECIAL FEATURE ABOVE. SCATTERED SHOWERS ARE OVER THE BAHAMAS FROM 21N-27N BETWEEN 71W-79W. A SURFACE TROUGH IS OVER THE CENTRAL ATLANTIC FROM 30N55W TO 24N60W MOVING E. SCATTERED SHOWERS ARE WITHIN 30 NM OF THE TROUGH. A WEAK 1018 MB HIGH IS OVER THE E ATLANTIC NEAR 26N24W. A THICK LAYER OF SAHARAN DUST IS NOTED ON THE METEOSAT-9 SAL PRODUCT OVER THE E ATLANTIC FROM 15N-30N E OF 40W. IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS CENTERED NEAR 29N48W SUPPORTING THE W ATLANTIC SURFACE TROUGH. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA