000 AXNT20 KNHC 081157 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT SEP 08 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1030 UTC. ...SPECIAL FEATURES... HURRICANE MICHAEL IS CENTERED NEAR 32.2N 41.8W AT 08/0900 UTC OR ABOUT 925 MI...1490 KM WSW OF THE AZORES...MOVING NNW AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 974 MB. MAXIMUM SUSTAINED WIND SPEED IS 85 KT WITH GUSTS TO 105 KT. NUMEROUS MODERATE TO STRONG CONVECTION IS FROM 30N-34N BETWEEN 39W-44W. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. TROPICAL STORM LESLIE IS CENTERED NEAR 28.3N 62.5W AT 08/1200 UTC OR ABOUT 310 MI...500 KM SSE OF BERMUDA...MOVING N AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 986 MB. MAXIMUM SUSTAINED WIND SPEED IS 55 KT WITH GUSTS TO 65 KT. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 25N-32N BETWEEN 59W-66W. SEE LATEST NHC INTERMEDIATE PUBLIC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT2/WTNT32 AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS. A TROPICAL WAVE AND ASSOCIATED 1011 MB LOW MOVED OFF THE COAST OF WEST AFRICA LATE LAST NIGHT AND EARLIER THIS MORNING...WITH THE WAVE AXIS ANALYZED FROM 22N16W TO THE LOW LEVEL CENTER NEAR 14N20W...MOVING W AT 15 KT. THIS SYSTEM COINCIDES WITH A SURGE OF DEEP LAYER MOISTURE NOTED ON TOTAL PRECIPITABLE WATER IMAGERY. NUMEROUS MODERATE/SCATTERED STRONG CONVECTION IS AFFECTING THE CAPE VERDE ISLANDS FROM 10N-19N BETWEEN 25W-18W. THE WAVE HAS POTENTIAL FOR DEVELOPMENT AND CONTAINS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ...TROPICAL WAVES... SEE SPECIAL FEATURES SECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS W AFRICA TO THE TROPICAL WAVE AND ASSOCIATED LOW MENTIONED ABOVE CONTINUING GENERALLY WESTWARD ALONG 11N24W 12N34W TO 10N49W...WHERE THE ITCZ DEVELOPS AND CONTINUES TO THE COAST OF TRINIDAD AND TOBAGO NEAR 10N61W. BESIDES CONVECTION NEAR THE TROPICAL WAVE AND ASSOCIATED LOW... SCATTERED MODERATE CONVECTION IS FROM 6N-10N BETWEEN 15W-28W... AND FROM 8N-11N BETWEEN 30W-45W. A SURFACE TROUGH IS ANALYZED 200 NM N OF THE MONSOON TROUGH AND WEST OF THE TROPICAL WAVE FROM 19N33W TO 14N30W. SCATTERED MODERATE CONVECTION IS WITHIN 60 NM O EITHER SIDE OF THE TROUGH AXIS N OF 16N. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER LEVEL ANTI-CYCLONIC CIRCULATION IS CENTERED OVER S-ERN TEXAS ON WATER VAPOR IMAGERY. NNE UPPER LEVEL FLOW AROUND THE ERN SIDE OF THE CIRCULATION EXTENDS ACROSS THE GULF CARRYING A DRY AND SUBSIDENT AIRMASS ALOFT ACROSS THE AREA THIS MORNING. THIS ENVIRONMENT ALOFT IS SUPPRESSING DEEP CONVECTION MAINTAINING FAIR CONDITIONS ACROSS THE DISCUSSION AREA...EXCEPT FOR A WEAK 1009 MB SURFACE LOW ANALYZED IN THE N-CENTRAL BASIN CENTERED NEAR 28N88W...WITH A SURFACE TROUGH EXTENDING SW FROM THE LOW CENTER TO NEAR 26N93W. NIGHT VISION SATELLITE IMAGERY SHOWS SCATTERED WEAK SHOWERS MAINLY TO THE ESE OF THIS SYSTEM...WITHIN 60-120 NM. THIS SYSTEM IS EXPECTED TO BEGIN TO DRIFT NORTHEASTWARD AND GAIN SPEED LATER THIS MORNING...BECOMING EMBEDDED IN A FRONTAL SYSTEM SWEEPING ACROSS THE SE CONUS WITHIN THE NEXT 24 HOURS. THIS FRONT WILL BEGIN TO AFFECT THE NW GULF BASIN LATER THIS AFTERNOON. OTHERWISE...WEAK SURFACE RIDGING COVERS THE REMAINDER OF THE BASIN EXTENDING ACROSS THE SOUTHERN GULF. CARIBBEAN SEA... WATER VAPOR IMAGERY SHOWS DRY AIR ALOFT AND STRONG SUBSIDENCE COVERING MUCH OF THE CARIBBEAN BASIN THIS MORNING...BETWEEN AN ELONGATED DRY UPPER TROUGH MOVING ACROSS THE NW CARIBBEAN AND AN UPPER ANTI-CYCLONIC CIRCULATION CENTERED WELL ENE OF PUERTO RICO. THIS SCENARIO IS SUPPORTIVE OF FAIR WEATHER CONDITIONS ACROSS MOST OF THE DISCUSSION AREA...EXCEPT FOR SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS OVER THE SW BASIN S OF 16N W OF 80W DUE TO CLOSE PROXIMITY TO THE ERN PACIFIC MONSOON TROUGH EXTENDING THROUGH INLAND PORTIONS OF COSTA RICA AND PANAMA TO NRN COLOMBIA. TRADEWIND FLOW OF 10-15 KT IS ACROSS THE MAJORITY OF THE BASIN WITH SOME STRONGER WINDS UP TO 20 KT NEAR THE COAST OF COLOMBIA. FAIR CONDITIONS WILL CONTINUE ACROSS THE MAJORITY OF THE BASIN WITH SHOWERS AND THUNDERSTORMS LINGERING OVER THE SW CORNER DURING THE NEXT 24 HOURS. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH COVERS THE WRN ATLC W OF TROPICAL STORM LESLIE. HOWEVER...WATER VAPOR IMAGERY REVEALS MOSTLY DRY AIR EMBEDDED AROUND THE UPPER TROUGH...ALLOWING FOR ONLY A FEW ISOLATED SHOWERS N OF THE NW BAHAMAS FROM 26N-32N BETWEEN 73W-80W. A WEAK 1015 MB HIGH IS ANALYZED RIGHT IN THIS REGION CENTERED NEAR 29N74W. THIS FEATURE IS HELPING TO MAINTAIN FAIR WEATHER ASIDE THE AREA OF SHOWERS ALREADY MENTIONED. TO THE EAST...TROPICAL STORM LESLIE SPINS IN THE CENTRAL ATLC PRODUCING A LARGE AREA OF WINDS...SEAS ...AND CONVECTION. SMALL BUT MIGHTY HURRICANE MICHAEL IS WELL TO THE ENE OF LESLIE. SEE SPECIAL FEATURES SECTION FOR MORE DETAILS ON BOTH SYSTEMS. THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS DOMINATED BY A BROAD UPPER LEVEL RIDGE COVERING THE ERN ATLC E OF 40W...AND A SURFACE 1023 MB HIGH NEAR 33N25W KEEPING FAIR WEATHER CONDITIONS ACROSS THE AREA. THE FAIR WEATHER ENVIRONMENT IS ENHANCED ALOFT BY SAHARAN DUST NOTED ON METEOSAT-9 SAL PRODUCT. A VIGOROUS FRONTAL SYSTEM CURRENTLY MOVING ACROSS THE SE CONUS WILL BEGIN TO AFFECT THE FAR WRN ATLC OVER THE NEXT 24 HOURS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA