000 AXNT20 KNHC 030002 TWDAT TROPICAL WEATHER DISCUSSION...AMENDED NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE AUG 02 2011 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2345 UTC. ...SPECIAL FEATURE... TROPICAL STORM EMILY IS CENTERED NEAR 16.0N 66.1W AT 03/0000 UTC OR ABOUT 165 MI S OF SAN JUAN PUERTO RICO MOVING W AT 12 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB. MAXIMUM SUSTAINED WIND SPEED IS 50 MPH WITH GUSTS TO 55 KT. EMILY CONTINUES MOVING WESTWARD. THE OUTER RAINBANDS ARE MOVING ACROSS PUERTO RICO AND THE LESSER ANTILLES. ACCORDING TO THE WEATHER SERVICE OFFICE IN SAN JUAN...GENERATED RAIN ACCUMULATIONS ARE 1 INCH AT THE MOMENT. HEAVY CONVECTION ASSOCIATED TO THE CORE OF THE SYSTEM IS NOT AFFECTING LAND AT THE MOMENT. THE DOMINICAN REPUBLIC ARE STARTING TO RECEIVE SOME RAIN FROM THE OUTER RAINBANDS OF EMILY. 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 IN THE EASTERN ATLANTIC FROM 11N30W TO 19N29W MOVING W AT 15-20 KT. THERE IS A LOW PRESSURE OF 1008 MB CENTERED AT 11N30W ASSOCIATED TO THIS WAVE. A CLUSTER OF MODERATE TO ISOLATED STRONG CONVECTION LIES AHEAD OF THIS WAVE ABOUT 388 NM. ANOTHER AREA OF CONVECTION LIES BEHIND THE WAVE FROM 5N-13N BETWEEN 20W-30W. TROPICAL WAVE IS ANALYZED FROM 9N50W TO 18N52W MOVING W AT 15 KT. AT THE TIME THERE IS NO SIGNIFICANT CONVECTION ASSOCIATED TO IT SINCE MOST OF THE MOISTURE LIES AHEAD AND IS MOSTLY ASSOCIATED TO T.S. EMILY. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 14N17W ALONG 11N30W 12N40W TO 10N50W. ISOLATED MODERATE TO STRONG CONVECTION LIES S OF THE TROUGH FROM 5N-11N BETWEEN 20W-30W. A CLUSTER OF MODERATE TO STRONG CONVECTION IS LOCATED S OF THE TROUGH AHEAD OF A TROPICAL WAVE FROM 8N-11N BETWEEN 33W-37W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY SHOWS A SHARP UPPER LEVEL TROUGH MOVING OFF THE EASTERN CONUS SEABOARD. THE SOUTHERN EXTENSION OF ENERGY FROM THE UPPER TROUGH WAS DRAGGED INTO THE NE GULF BY THE ANTICYCLONIC FLOW FROM AN UPPER RIDGE CENTERED OVER THE SE CONUS. THIS PIECE OF ENERGY IS NOW EMBEDDED IN A DRY SUBSIDENT AIRMASS ALOFT SUPPRESSING PRIOR DEEP CONVECTION...AND LEAVING ONLY A FEW ISOLATED SHOWERS N OF 27N E OF 80W. AN UPPER LEVEL LOW MOVES ACROSS THE CITY OF VERACRUZ IN MEXICO. THIS FEATURE IS PROVIDING SOME MID TO UPPER LEVEL LIFTING ACROSS THE BAY OF CAMPECHE THIS EVENING...GENERATING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ACROSS THIS AREA S OF 22N. THE REMAINDER OF THE GULF IS EXPERIENCING FAIR WEATHER CONDITIONS THIS AFTERNOON...WITH LIGHT TO MODERATE ANTICYCLONIC WINDS OVER MOST OF THE AREA...ANCHORED BY A 1015 MB HIGH OVER THE CENTRAL GULF NEAR 26N90W. THE SURFACE RIDGE IS FORECAST TO REMAIN ACROSS THE GULF 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. FOR MORE INFORMATION...SEE SPECIAL FEATURE ABOVE. THE ONLY OTHER AREA OF ACTIVE WEATHER BESIDES EMILY IS OVER THE FAR SW BASIN WITH ISOLATED WEAK SHOWERS AND THUNDERSTORMS S OF 12N W OF 74W DUE TO CLOSE PROXIMITY TO THE MONSOON TROUGH EXTENDING ACROSS PANAMA TO NORTHERN COLOMBIA. OTHERWISE...MOSTLY FAIR WEATHER WITH LIGHT TO MODERATE TRADE WINDS IS OBSERVED ELSEWHERE ACROSS THE DISCUSSION AREA THIS EVENING. ATLANTIC OCEAN... A SHARP UPPER LEVEL TROUGH MOVES OFF THE EASTERN CONUS SEABOARD ACROSS THE WESTERN ATLC. THIS UPPER FEATURE SUPPORTS A NEARLY STATIONARY LOW PRESSURE/FRONTAL SYSTEM THAT ENTERS OUR DISCUSSION AREA AS A SURFACE TROUGH ALONG 32N3W INTO NORTHERN FLORIDA ALONG 30N1W. ANOTHER SURFACE TROUGH IS ANALYZED FROM 29N73W INTO SOUTHERN FLORIDA ALONG THE CITY OF BOCA RATON. SCATTERED WEAK TO MODERATE CONVECTION IS N OF 27N BETWEEN 68W-77W. A BROAD REGION OF SCATTERED WEAK CONVECTION LINKED TO THE MOISTURE BEING CARRIED BY T.S. EMILY AND A TROPICAL WAVE POSITIONED ALONG 52W IS LOCATED FROM 18N-21N BETWEEN 50W-60W. A LARGE SURFACE RIDGE DOMINATES THE ATLC BASIN...ANCHORED BY A 1025 MB HIGH N OF THE DISCUSSION AREA...SW OF THE AZORES NEAR 33N33W. THIS FEATURE EXTENDS A RIDGE AXIS WSW TO THE BAHAMAS. THE CIMSS SAHARAN AIR LAYER TRACKING PRODUCT AND LAST VISIBLE METEOSAT-9 SATELLITE IMAGERY OF THE DAY SHOWED A LARGE AREA OF AFRICAN DUST N 14N E OF 55W. WITHIN THIS AREA OF DRY DUSTY AIR...AN UPPER LEVEL CYCLONIC CIRCULATION WAS FOUND ON WATER VAPOR NEAR 28N38W WITHOUT ANY DEEP CONVECTION. FOR INFORMATION ABOUT TROPICAL WAVES AND MONSOON TROUGH...SEE THESE SECTIONS AT THE BEGINNING OF THE DISCUSSION. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FG/NAR