000 AXNT20 KNHC 121748 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN SEP 12 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... THE CENTER OF HURRICANE IGOR AT 12/1500 UTC IS NEAR 17.7N 45.7W. IGOR IS MOVING WESTWARD 11 KT. THIS POSITION IS ABOUT 1145 MI... 1840 KM E OF THE NORTHERN LEEWARD ISLANDS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 970 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 90 KT WITH GUSTS TO 110 KT. PLEASE READ THE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT1/ WTNT31 KNHC AND THE FULL FORECAST AND ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. NUMEROUS STRONG STRONG CONVECTION IS WITHIN 60 NM OF THE CENTER. IN ADDITION SCATTERED MODERATE CONVECTION IS FROM 15N-19N BETWEEN 43W-47W. THE CENTER OF TROPICAL DEPRESSION TWELVE AT 12/1800 UTC IS NEAR 13.1N 22.2W. T.D. TWELVE IS MOVING WESTWARD 12 KT. THIS POSITION IS ABOUT 190 MI...305 KM SE OF THE SOUTHERNMOST CAPE VERDE ISLANDS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 30 KT WITH GUSTS TO 40 KT. PLEASE READ THE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT2/ WTNT32 KNHC AND THE FULL FORECAST AND ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS. WIDELY SCATTERED MODERATE CONVECTION IS FROM 11N-17N BETWEEN 20W-26W. A 1007 MB LOW PRESSURE CENTER IS NEAR 16N72W...ABOUT 120 NM SOUTH OF HISPANIOLA. LOCALLY HEAVY RAINFALL IS OVER PUERTO RICO...AND HISPANIOLA THAT MAY CAUSE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES...ESPECIALLY IN MOUNTAINOUS TERRAIN. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 13N-19N BETWEEN 70W-76W...AND FROM 17N-21N BETWEEN 66W-70W. IT IS POSSIBLE THAT A TROPICAL DEPRESSION MAY FORM DURING THE NEXT 48 HOURS. ...TROPICAL WAVES... NONE. ...THE ITCZ... THE ITCZ AXIS IS SW OF T.D.TWELVE ALONG 5N23W 8N30W 12N36W... AND SW OF HURRICANE IGOR ALONG 12N45W 10N52W 12N60W. ISOLATED MODERATE CONVECTION IS FROM 3N-7N BETWEEN 8W-32W...AND FROM 9N-12N BETWEEN 41W-50W. ...DISCUSSION... THE GULF OF MEXICO... A SURFACE TROUGH IS OVER THE BAY OF CAMPECHE ALONG 21N94W 17N93W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 17N-21N BETWEEN 92W-98W. A 1019 MB HIGH IS CENTERED OVER THE CENTRAL GULF OF MEXICO NEAR 27N90W. A COLD FRONT DIPS INTO THE NORTHERN FLORIDA PANHANDLE ALONG 31N85W 30N89W. SCATTERED SHOWERS ARE WITHIN 30 NM OF THE TROUGH. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS CENTERED OVER E TEXAS NEAR 30N95W. NE UPPER LEVEL FLOW COVERS THE GULF. CONSIDERABLE UPPER LEVEL MOISTURE IS OVER THE BAY OF CAMPECHE S OF 22N. STRONG SUBSIDENCE IS OVER THE REMAINDER OF THE GULF. EXPECT THE COLD FRONT TO TRAVERSE N FLORIDA OVER THE NEXT 24 HOURS WITH SHOWERS. ALSO EXPECT CONVECTION OVER THE YUCATAN PENINSULA AND FURTHER W OVER S MEXICO. THE CARIBBEAN SEA... A 1007 MB LOW IS S OF HISPANIOLA MOVING W. SEE THE SPECIAL FEATURES SECTION ABOVE. ELSEWHERE...ISOLATED MODERATE CONVECTION IS OVER THE SW CARIBBEAN FROM 7N-12N BETWEEN 75W-84W. SIMILAR CONVECTION IS INLAND OVER N GUATEMALA. A RATHER LAX SURFACE PRESSURE GRADIENT IS OVER THE CARIBBEAN SEA THUS TRADEWINDS ARE MOSTLY 10-15 KT EXCEPT NEAR THE CENTRAL CARIBBEAN LOW WHERE 20 KT WINDS ARE NOTED. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS OVER HISPANIOLA NEAR 19N70W. CONSIDERABLE UPPER LEVEL MOISTURE COVERS MOST OF THE CENTRAL AND SOUTHERN CARIBBEAN. EXPECT THE CENTRAL CARIBBEAN LOW TO MOVE W AT 15 KT WITH CONVECTION AND DOMINATE THE WEATHER OVER THE NEXT 24 HOURS. THE ATLANTIC OCEAN... A COLD FRONT IS OVER THE W ATLANTIC ALONG 31N59W 29N64W. A DISSIPATING COLD FRONT CONTINUES TO 27N69W. SCATTERED SHOWERS ARE WITHIN 60 NM OF THE FRONT. A 1033 MB HIGH IS OVER THE E ATLANTIC NEAR 45N20W PRODUCING FAIR WEATHER. A SURFACE RIDGE AXIS EXTENDS SW TO 30N45W. OF NOTE IN THE UPPER LEVELS...AN UPPER LEVEL TROUGH IS OVER THE W ATLANTIC N OF 25N W OF 75W. AN UPPER LEVEL RIDGE IS N OF 25N BETWEEN 65W-75W. AN UPPER LEVEL TROUGH IS OVER THE CENTRAL ATLANTIC N OF 20N BETWEEN 50W-65W. AN UPPER LEVEL RIDGE IS N OF 20N BETWEEN 40W-50W. AN UPPER LEVEL LOW IS CENTERED OVER THE E ATLANTIC NEAR 29N32W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA