000 AXNT20 KNHC 220003 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE SEP 21 2010 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... POST-TROPICAL IGOR IS NEAR 49.3N 51.7W AT 21/2100 UTC MOVING NNE AT 34 KT. THIS POSITION IS ABOUT 109 NM TO THE NNE OF ST. JOHNS NEWFOUNDLAND. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 950 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 70 KT WITH GUSTS TO 90 KT. IGOR IS EMBEDDED WITHIN SOUTHWESTERLY SHEAR AS DEEP CONVECTIVE PRECIPITATION REMAINS DISPLACED TO THE NORTH OF THE CENTER. THE LAST ADVISORY FOR IGOR BY THE NATIONAL HURRICANE CENTER WAS ISSUED AT 2100 UTC AS THE SYSTEM BECOMES EXTRATROPICAL. PLEASE READ THE LAST NHC PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT1/WTNT31 AND THE LAST FORECAST ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. THE CENTER OF TROPICAL STORM LISA IS NEAR 18.3N 31.6W AT 21/2100 UTC...OR ABOUT 456 NM TO THE WNW OF THE CAPE VERDE ISLANDS...MOVING NORTH 4 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 40 KT WITH GUSTS TO 50 KT. PLEASE READ THE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT4/WTNT34 AND THE FULL FORECAST ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/ WTNT24 KNHC FOR MORE DETAILS. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 17N-19N BETWEEN 31W-33W...AND FROM 19N-21N BETWEEN 26W-31W. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 21N17W 16N19W 10N19W MOVING W AT 5 KT. A 1008 MB LOW PRESSURE CENTER IS EMBEDDED ON THE WAVE AXIS NEAR 16N19W. STRONG RAINSHOWERS AND THUNDERSTORMS ARE WITHIN A 30 NM RADIUS OF THE LOW. WIDELY SCATTERED MODERATE CONVECTION IS ALSO W OF THE WAVE AXIS FROM 8N-13N BETWEEN 21W-23W. AN EASTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 64W S OF 17N MOVING W AT 10 KT. A 1009 MB LOW PRESSURE CENTER IS EMBEDDED ON THE WAVE AXIS NEAR 12N64W. CLUSTERS OF WIDELY SCATTERED MODERATE CONVECTION IS OVER THE E CARIBBEAN FROM 10N-17N BETWEEN 62W-72W. ...THE ITCZ... LARGE-SCALE CYCLONIC FLOW THAT IS ASSOCIATED WITH THE MONSOONAL TROUGH COVERS THE AREA FROM 6N-22N TO THE EAST OF 48W. THE TRADITIONAL ITCZ AXIS PICKS UP NEAR 11N48W TO 12N60W. ISOLATED MODERATE CONVECTION IS FROM 8N-11N BETWEEN 43W-54W. SCATTERED MODERATE CONVECTION IS FROM 8N-13N BETWEEN 54W-59W. ...DISCUSSION... THE GULF OF MEXICO... SURFACE RIDGING IS OVER THE GULF OF MEXICO WITH RETURN FLOW OVER THE NW GULF PRODUCING WIDELY SCATTERED MODERATE CONVECTION ALONG THE COAST OF NE MEXICO FROM 22N-26N BETWEEN 95W-98W. SCATTERED MODERATE CONVECTION IS ALSO INLAND OVER THE YUCATAN PENINSULA AND S MEXICO S OF 21N. MOSTLY FAIR WEATHER IS OVER FLORIDA AND THE SE GULF. IN THE UPPER LEVELS... AN UPPER LEVEL RIDGE IS OVER THE W GULF W OF 90W. AN UPPER LEVEL LOW IS CENTERED OVER THE NE GULF NEAR 28N86W. CONSIDERABLE UPPER LEVEL MOISTURE COVERS MOST OF THE GULF S OF 28N AND W OF 84W. EXPECT... CONTINUED CONVECTION OVER THE YUCATAN PENINSULA AND THE W GULF W OF 94W OVER THE NEXT 24 HOURS. THE CARIBBEAN SEA... A TROPICAL WAVE WITH EMBEDDED LOW IS OVER THE E CARIBBEAN SEE ABOVE. A GOOD AMOUNT OF PRECIPITATION HAS FALLEN OVER ARUBA BONAIRE AND CURACAO WITH MORE EXPECTED AS THE SYSTEM MOVES W AT 10 KT. ISOLATED MODERATE CONVECTION IS ALSO OVER OVER HISPANIOLA AND E CUBA. ELSEWHERE...WIDELY SCATTERED MODERATE CONVECTION IS INLAND OVER CENTRAL AMERICA FROM PANAMA TO GUATEMALA. IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS CENTERED OVER THE CAYMAN ISLANDS NEAR 19N82W. AN UPPER LEVEL RIDGE IS OVER THE E CARIBBEAN E OF 75W. CONSIDERABLE UPPER LEVEL MOISTURE IS OVER THE CARIBBEAN AND CENTRAL AMERICA. EXPECT...CONTINUED SHOWERS AND CONVECTION OVER THE W CARIBBEAN W OF 75W AND OVER THE S CARIBBEAN S OF 16N OVER THE NEXT 24 HOURS. THE ATLANTIC OCEAN... POST-TROPICAL IGOR...T.S. LISA...TOGETHER WITH A TROPICAL WAVE AND EMBEDDED LOW ARE THE PRIMARY SURFACE FEATURES OVER THE ATLANTIC. IGOR...A CATEGORY ONE HURRICANE...IS MOVING AWAY FROM NEWFOUNDLAND AND IS STILL PRODUCING HURRICANE FORCE WINDS. SEE ABOVE. LISA IS DRIFTING N AND SLOWLY INTENSIFYING. VISIBLE IMAGERY ALSO SHOWS A LARGE AREA OF DUST OVER THE E ATLANTIC FROM 15N-25N E OF 60W TO W AFRICA. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA