000 AXNT20 KNHC 131747 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT MON SEP 13 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... HURRICANE IGOR IS CENTERED NEAR 17.5N 49.7W AT 13/1500 UTC OR ABOUT 765 NM E OF THE NORTHERN LEEWARD ISLANDS MOVING W AT 9 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 933 MB. MAXIMUM SUSTAINED WIND SPEED IS 130 KT WITH GUSTS TO 160 KT. VISIBLE SATELLITE PRESENTATION SHOWS IGOR HAS A WELL-DEFINED EYE AND FAIRLY SYMMETRICAL CONVECTION. NUMEROUS STRONG CONVECTION IS WITHIN 90 NM OF THE CENTER WHILE NUMEROUS MODERATE AND SCATTERED STRONG CONVECTION IS ELSEWHERE FROM 15N-21N BETWEEN 45W-53W. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. TROPICAL STORM JULIA IS CENTERED NEAR 15.1N 26.7W AT 13/1800 UTC OR ABOUT 135 NM W OF THE SOUTHERNMOST CAPE VERDE ISLANDS MOVING WNW AT 11 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. GRADUAL STRENGTHENING IS FORECAST OVER THE NEXT COUPLE OF DAYS DUE TO A FAVORABLE UPPER LEVEL DIFFLUENT ENVIRONMENT. NUMEROUS MODERATE AND SCATTERED STRONG CONVECTION IS FROM 13N-17N BETWEEN 25W-29W. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT2/WTNT32 KNHC AND THE FULL FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS. A BROAD LOW PRESSURE AREA IS LOCATED IN THE WESTERN CARIBBEAN SEA FOCUSED ON A 1008 MB LOW CENTERED NEAR 16N77W. A SURFACE TROUGH EXTENDS FROM NEAR 19N75W THROUGH THE LOW CENTER TO 10N81W MOVING WNW NEAR 10 KT. SCATTERED MODERATE TO STRONG CONVECTION IS OCCURRING FROM 14N-20N BETWEEN 75W-81W AND IS LIKELY ENHANCED BY AN UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED OVER HISPANIOLA NEAR 19N73W. ISOLATED MODERATE CONVECTION IS ALSO FROM 13N-18N BETWEEN 72W-75W AND FROM 09N-13N BETWEEN 76W-82W. WHILE CONVECTION ALONG THE SURFACE TROUGH AND NEAR THE LOW CENTERED REMAIN LARGELY UNORGANIZED...ENVIRONMENTAL CONDITIONS REMAIN FAVORABLE FOR DEVELOPMENT OF A TROPICAL CYCLONE OVER THE NEXT 48 HOURS. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 08N27W 09N33W 15N42W RESUMING NEAR 11N54W 10N60W 11N68W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 03N-08N BETWEEN 08W-21W...AND FROM 05N-10N BETWEEN 23W-31W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER THE NW GULF NEAR 29N94W AND IS PROVIDING THE FLORIDA PENINSULA AND MUCH OF THE GULF N OF 22N WITH NE TO E UPPER LEVEL FLOW. WATER VAPOR IMAGERY ALSO INDICATES THIS IS USHERING IN A MODERATELY DRY AIRMASS OVER THE EASTERN GULF E OF 90W. HOWEVER...AS AN UPPER LEVEL SHORTWAVE TROUGH MOVES EASTWARD FROM THE W ATLC WATERS...A LINGERING FRONTAL BOUNDARY IS ANALYZED ACROSS THE CENTRAL FLORIDA PENINSULA FROM CAPE CANAVERAL TO NEW PORT RICHEY AND INTO A 1013 MB LOW CENTERED NEAR 28N83W. A STATIONARY FRONT THEN EXTENDS WESTWARD FROM THE LOW ALONG 28N TO THE TEXAS COAST NEAR GALVESTON. DUE TO THE STRONGER SUBSIDENCE ALOFT OVER THE EASTERN GULF...ONLY A ISOLATED SHOWERS ARE WITHIN 60 NM S OF THE FRONT BETWEEN 91W-96W. ELSEWHERE N OF 22N PRIMARILY NE TO E WINDS UP TO 15 KT. FINALLY...A SURFACE TROUGH IS FROM 19N-22N ALONG 93W AND IS PROVIDING FOCUS FOR SCATTERED SHOWERS AND ISOLATED TSTMS OVER THE BAY OF CAMPECHE S OF 21N. CARIBBEAN SEA... AN UPPER LEVEL ANTICYCLONE IS CENTERED OVER HISPANIOLA NEAR 19N73W AND CONTINUES TO PROVIDE MUCH OF THE BASIN WITH UPPER LEVEL EASTERLY FLOW. A WEAKNESS ON THE SW PERIPHERY OF THE RIDGE IS ASSOCIATED WITH THE 1008 MB SPECIAL FEATURES LOW CENTER AND SURFACE TROUGHING ACROSS THE WESTERN CARIBBEAN. NUMEROUS SHOWERS AND SCATTERED TSTMS ARE N OF 14N...OVER JAMAICA...TO THE SE COAST OF CUBA NEAR 20N BETWEEN 75W-81W. ELSEWHERE BETWEEN 71W AND 83W...ISOLATED SHOWERS AND TSTMS ARE OCCURRING DUE TO THE LARGE-SCALE LOW-LEVEL TROUGHING THAT EXISTS OVER THE CENTRAL AND WESTERN CARIBBEAN. WATER VAPOR IMAGERY INDICATES THAT MOSTLY DRY AIR AND STRONG SUBSIDENCE IS OVER THE NE CARIBBEAN AND LEEWARD ISLANDS PROVIDING OVERALL FAIR CONDITIONS AND CLEAR SKIES THIS AFTERNOON. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH AXIS EXTENDS OVER THE WESTERN ATLC FROM NORTH OF THE DISCUSSION AREA NEAR 35N70W TO THE CENTRAL BAHAMAS NEAR 25N75W. THIS UPPER LEVEL TROUGHING SUPPORTS A 1009 MB LOW CENTERED NEAR 35N72W AND A COLD FRONT THAT EXTENDS FROM THE LOW TO 31N77W. WHILE THE FRONT LACKS ANY SIGNIFICANT DEEP CONVECTION...POSSIBLE ISOLATED SHOWERS ARE FROM 30N-32N W OF 77W. A SURFACE TROUGH EXTENDS FROM 31N74W EAST OF THE COLD FRONT TO THE FLORIDA PENINSULA NEAR CAPE CANAVERAL. COASTAL DOPPLER RADAR INDICATES ISOLATED SHOWERS WITHIN 90 NM S OF THE SURFACE TROUGH OVER THE W ATLC WATERS W OF 77W. FARTHER SOUTH...WHILE THE UPPER LEVEL TROUGH AXIS WEAKENS ACROSS CENTRAL CUBA...MOIST SW FLOW IS OVER FAR SOUTHERN PORTIONS OF THE SW NORTH ATLC. THIS ALONG WITH LOW-LEVEL TROUGHING EXTENDING FROM THE SPECIAL FEATURES LOW IN THE WESTERN CARIBBEAN SEA...IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS FROM 20N-23N BETWEEN 69W-78W...INCLUDING THE SE BAHAMAS...TURKS AND CAICOS ISLANDS... AND EASTERN CUBA. OVER THE CENTRAL ATLC...ANOTHER UPPER LEVEL LOW IS CENTERED NORTH OF THE AREA NEAR 39N49W AND SUPPORTS A COLD FRONT EXTENDING FROM 32N53W TO 28N60W TO 27N71W. ISOLATED SHOWERS ARE WITHIN 60 NM EITHER SIDE OF THE FRONT BETWEEN 51W-71W...AND SCATTERED SHOWERS AND ISOLATED TSTMS ARE N OF 29N BETWEEN 45W-51W. THE REMAINDER OF THE EASTERN ATLC IS DOMINATED BY SURFACE RIDGING ANCHORED BY A 1032 MB HIGH CENTERED N OF THE AZORES NEAR 44N24W. AN UPPER LEVEL ANTICYCLONE IS CENTERED OVER W AFRICA NEAR 20N06W WITH AN UPPER LEVEL RIDGE AXIS EXTENDING ALONG 19N TO NORTH OF T.S. JULIA NEAR 19N27W. SCATTERED SHOWERS AND TSTMS ARE ENHANCED DUE TO UPPER LEVEL DIFFLUENCE NE OF THE CAPE VERDE ISLANDS FROM 17N-21N BETWEEN 19W-24W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN