000 AXNT20 KNHC 021808 AAA TWDAT TROPICAL WEATHER DISCUSSION...AMENDED NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE AUG 02 2011 AMENDED/UPDATED SPECIAL FEATURES INFORMATION ON T.S. EMILY 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... TROPICAL STORM EMILY IS CENTERED NEAR 15.6N 64.8W AT 02/1800 UTC OR ABOUT 185 NM S-SE OF SAN JUAN PUERTO RICO MOVING W AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. A GRADUAL INCREASE IN FORWARD SPEED IS ANTICIPATED LATER TODAY WITH THE FORECAST TRACK W-NW TOWARDS THE SOUTHERN COAST OF HISPANIOLA. SCATTERED MODERATE TO STRONG CONVECTION IS LOCATED WITHIN 120 NM OF THE CENTER. ELSEWHERE SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 12N-17N BETWEEN 59W-64W... PRIMARILY EAST OF EMILY AND ACROSS THE LESSER ANTILLES. LOOKING AHEAD AS EMILY IMPACTS PUERTO RICO...THE US/UK VIRGIN ISLANDS... THE DOMINICAN REPUBLIC...AND HAITI...ASIDE FROM TROPICAL STORM FORCE WINDS...HEAVY AMOUNTS OF PRECIPITATION ARE EXPECTED. 4 TO 6 INCHES ARE EXPECTED OVER THESE AREAS WITH MAXIMUM AMOUNTS TO 10 INCHES LOCALLY DURING THE NEXT 24-48 HOURS. LIFE-THREATENING FLASH FLOODING AND MUDSLIDES WILL BE POSSIBLE ACROSS AREAS OF MOUNTAINOUS TERRAIN. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT5/WTNT35 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IS ANALYZED FROM 11N29W TO 17N30W MOVING W AT 20 KT. HOVMOLLER DIAGRAM ANALYSIS INDICATES THIS WAVE MOVED OFF THE W AFRICA COAST DURING THE DAY ON JULY 31ST. UPPER AIR TIME- SECTION ANALYSES FROM DAKAR SENEGAL ALSO CONFIRMS THE PASSAGE OF THE WAVE. WELL WEST OF THE CAPE VERDE ISLANDS AT THIS POINT...A BROAD LOW-LEVEL CYCLONIC CIRCULATION SURROUNDING THE WAVE AXIS N OF THE MONSOON TROUGH TO 16N IS BETWEEN 25W-37W. NO SIGNIFICANT CONVECTION IS ASSOCIATED WITH THE WAVE AT THIS TIME DUE TO THE LARGE PRESENCE OF AFRICAN DUST ACROSS THE EASTERN TROPICAL ATLC. TROPICAL WAVE IS ANALYZED FROM 07N52W TO 17N50W MOVING W AT 15 KT. THE WAVE REMAINS EMBEDDED WITHIN ELEVATED VALUES OF TOTAL PRECIPITABLE WATER VALUES W OF 46W TO TROPICAL STORM EMILY IN THE EASTERN CARIBBEAN SEA. WATER VAPOR IMAGERY INDICATES STRONG DRY AIR AND SUBSIDENCE ALOFT...THEREFORE NO SIGNIFICANT CONVECTION IS ASSOCIATED WITH THE WAVE AT THIS TIME. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 14N17W ALONG 10N33W 11N42W TO 09N50W. ISOLATED MODERATE CONVECTION IS FROM 09N-12N BETWEEN 22W-28W...AND FROM 08N-12N BETWEEN 30W-35W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER THE LOWER MISSISSIPPI RIVER VALLEY AND IS PROVIDING MUCH OF THE GULF WITH NORTHEASTERLY UPPER LEVEL FLOW. AT THE SURFACE...OVERALL RIDGING IS PROVIDING FAIR CONDITIONS W OF 90W. HOWEVER...A WEAKNESS EXISTS IN THIS RIDGE ACROSS THE NE GULF AND NORTHERN FLORIDA PENINSULA N OF 27N. A 1012 MB LOW IS ANALYZED NEAR 29N85W WITH A TRAILING SURFACE TROUGH EXTENDING SW TO 27N89W. MOSAIC DOPPLER RADAR IMAGERY AND LIGHTNING DATA INDICATES THAT SCATTERED SHOWERS AND TSTMS ARE OCCURRING FROM 27N-30N BETWEEN 84W-90W. THE SURFACE RIDGE IS FORECAST TO REMAIN ACROSS THE GULF ALONG 26N THROUGH THE WEEKEND. CARIBBEAN SEA... TROPICAL STORM EMILY CONTINUES TO BE THE PRIMARY FOCUS ACROSS THE EASTERN AND CENTRAL CARIBBEAN OVER THE NEXT FEW DAYS. AS NOTED ABOVE...LARGE AMOUNTS OF RAINFALL ARE ANTICIPATED ACROSS PUERTO RICO...THE US/UK VIRGIN ISLANDS...DOMINICAN REPUBLIC... AND HAITI WITH EMILY AS IT TRACKS W-NW TOWARDS THE SOUTHERN COAST OF HISPANIOLA. ONE FACTOR CONTRIBUTING IN A POSITIVE WAY TO EMILY IS A LARGE ANTICYCLONE CENTERED NEAR 16N71W AND ASSOCIATED RIDGE AXIS EXTENDING EASTWARD TO 14N44W. THE ONLY OTHER AREA OF ACTIVE WEATHER ACROSS THE CARIBBEAN ARE SOME SCATTERED SHOWERS AND ISOLATED TSTMS ACROSS BELIZE AND THE YUCATAN PENINSULA...INCLUDING THE ADJACENT COASTAL WATERS W OF 86W. THIS ACTIVITY IS LIKELY ENHANCED BY AN UPPER LEVEL LOW CENTERED IN THE SW GULF OF MEXICO NEAR 20N93W. THE REMAINDER OF THE CARIBBEAN BETWEEN 70W-85W IS UNDER MOSTLY CLEAR SKIES AND FAIR CONDITIONS WITH LIGHT EASTERLY WINDS OF 10-15 KT. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH IS EVIDENT ON WATER VAPOR IMAGERY ALONG THE EASTERN CONUS SEABOARD AND DIPS SOUTHWARD INTO THE DISCUSSION AREA TO A BASE NEAR 29N75W. THIS TROUGH SUPPORTS A 1011 MB LOW CENTERED NW OF BERMUDA NEAR 33N66W AND A STATIONARY FRONT ANALYZED FROM THE LOW SW ALONG 31N70W TO 29N78W. LOW-LEVEL MOISTURE CONTINUES TO CONVERGE ALONG THE FRONT AND GENERATE SCATTERED SHOWERS AND ISOLATED TSTMS WITHIN 150 NM EITHER SIDE OF THE BOUNDARY. THIS FRONTAL TROUGHING IS EXPECTED TO MOVE NE AND NORTH OF THE AREA OF THE NEXT 24 HOURS AS A SURFACE RIDGE AXIS CURRENTLY ALONG 25N SHIFTS NORTHWARD. THE REMAINDER OF THE EASTERN AND CENTRAL ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1025 MB HIGH CENTERED SW OF THE AZORES NEAR 34N33W. THE RIDGE AXIS EXTENDS FROM THE HIGH SW TO 25N64W THEN WESTWARD ACROSS THE CENTRAL BAHAMAS AND FLORIDA STRAITS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN