000 AXNT20 KNHC 211800 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... THE CENTER OF HURRICANE IGOR IS NEAR 48.5N 52.0W AT 21/1800 UTC MOVING NORTHEASTWARD 40 KT. THIS POSITION IS ABOUT 20 KM TO THE NORTH-NORTHEAST OF ST. JOHNS NEWFOUNDLAND. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 950 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 65 KT WITH GUSTS TO 80 KT. IGOR IS EMBEDDED WITHIN SOUTHWESTERLY SHEAR AS DEEP CONVECTIVE PRECIPITATION REMAINS DISPLACED TO THE NORTH OF THE CENTER. IGOR IS EXPECTED TO BECOME EXTRATROPICAL WITHIN THE NEXT 12 HOURS. PLEASE READ THE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT1/WTNT31 AND THE FULL FORECAST ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. THE CENTER OF TROPICAL STORM LISA IS NEAR 18.1N 31.7 AT 21/1500 UTC...OR ABOUT 385 NM TO THE WEST 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. STRONG RAINSHOWERS AND THUNDERSTORMS ARE FROM 18N TO 19N BETWEEN 31W AND 32W...WITHIN 30 NM ON EITHER SIDE OF 19N BETWEEN 30W AND 31W...WITHIN A 30 NM RADIUS OF 19N28W... WITHIN 30 NM ON EITHER SIDE OF 16N BETWEEN 32W AND 33W... AND FROM 12N TO 13N BETWEEN 33W AND 35W. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 20N19W 16N19W 12N17W 9N15W. A 1008 MB LOW PRESSURE CENTER IS ALONG THE WAVE NEAR 16N19W. STRONG RAINSHOWERS AND THUNDERSTORMS ARE WITHIN A 30 NM RADIUS OF 18N20W. OTHER RAINSHOWERS AND THUNDERSTORMS ARE FROM 11N TO 19N BETWEEN 19W AND 21W. AN EASTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 18N64W 12N63W 9N61W. A 1009 MB LOW PRESSURE CENTER IS ALONG THE WAVE NEAR 12N63W. LARGE-SCALE UPPER LEVEL CYCLONIC FLOW COVERS THE ATLANTIC OCEAN AND THE CARIBBEAN SEA FROM 13N TO 21N BETWEEN 52W AND 62W...AROUND AN 18N57W CYCLONIC CIRCULATION CENTER. A SECOND CYCLONIC CIRCULATION CENTER IS IN THE CARIBBEAN SEA NEAR 17N67W...ABOUT 70 NM TO THE SOUTH OF THE MONA PASSAGE. STRONG RAINSHOWERS AND THUNDERSTORMS ARE FROM 12N TO 15N BETWEEN 61W AND 68W. SCATTERED MODERATE RAINSHOWERS AND ISOLATED STRONG THUNDERSTORMS ARE FROM 11N TO 15N BETWEEN 53W AND 62W...AND FROM 14N TO 20N BETWEEN 69W AND 75W IN THE CARIBBEAN SEA AND PARTIALLY ACROSS AREAS OF HISPANIOLA. ...THE ITCZ... LARGE-SCALE CYCLONIC FLOW THAT IS ASSOCIATED WITH THE MONSOONAL TROUGH COVERS THE AREA FROM 6N TO 22N TO THE EAST OF 46W. SCATTERED MODERATE RAINSHOWERS AND ISOLATED STRONG THUNDERSTORMS ARE FROM 11N TO 15N BETWEEN 53W AND 62W...AND FROM 7N TO 10N BETWEEN 56W AND 60W. ...DISCUSSION... THE GULF OF MEXICO... AN UPPER LEVEL CYCLONIC CIRCULATION CENTER IS OVER THE NORTHWESTERN CORNER OF THE FLORIDA PANHANDLE. CYCLONIC FLOW COVERS THE GULF OF MEXICO AND U.S.A. GULF COASTAL AREAS FROM 26N TO 32N BETWEEN 83W AND 90W. EARLIER RAINSHOWERS APPEARED TO BE FROM 23N TO 25N BETWEEN 88W AND 90W ON THE SOUTHERN SIDE OF THE CYCLONIC FLOW. IT IS POSSIBLE THAT PRECIPITATION STILL REMAINS IN THAT AREA. HIGH LEVEL CLOUDS COVER THE GULF OF MEXICO FROM WESTERN CUBA TO 29N BETWEEN 83W AND 87W. ISOLATED MODERATE RAINSHOWERS ARE TO THE SOUTH OF 28N BETWEEN 92W AND THE MEXICO/ SOUTH TEXAS COAST...IN BROAD SURFACE LOW PRESSURE...AND UPPER LEVEL SHEARING ANTICYCLONIC FLOW. THE UPPER LEVEL TROUGH THAT PASSES THROUGH THE ATLANTIC OCEAN... ACROSS FLORIDA AND CUBA...INTO THE CARIBBEAN SEA TOWARD CENTRAL AMERICA... AN UPPER LEVEL TROUGH PASSES ON TOP OF BERMUDA...TO 26N75W IN THE ATLANTIC OCEAN TO THE EAST OF THE BAHAMAS...TO 23N78W BETWEEN ANDROS ISLAND AND CUBA...TO THE CAYMAN ISLANDS...TO EASTERN HONDURAS AND SOUTHWESTERN NICARAGUA. ISOLATED MODERATE RAINSHOWERS AND POSSIBLE THUNDERSTORMS ARE IN THE CARIBBEAN SEA TO THE NORTH OF 15N TO THE WEST OF JAMAICA...AND IN THE COASTAL PLAINS/COASTAL WATERS FROM WESTERN PANAMA TO NORTHERN NICARAGUA...AND IN THE ATLANTIC OCEAN FROM 20N TO 22N BETWEEN 68W AND 75W. THE REST OF THE CARIBBEAN SEA... BROAD SURFACE-TO-LOW LEVEL LOW PRESSURE COVERS THE AREA TO THE SOUTH OF 15N TO THE WEST OF 75W. ISOLATED MODERATE RAINSHOWERS ARE TO THE SOUTH OF 14N BETWEEN 75W AND 82W. THE REST OF THE ATLANTIC OCEAN... AN UPPER LEVEL TROUGH PASSES THROUGH 32N26W TO 26N32W TO 21N33W. A SURFACE TROUGH IS ALONG 31N59W 27N63W 24N71W. SURFACE ANTICYCLONIC WIND FLOW MOVES AROUND A 1018 MB HIGH PRESSURE CENTER THAT IS NEAR 27N48W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT