000 AXNT20 KNHC 160004 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED AUG 15 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND THE 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... TROPICAL STORM ERIN REMAINS POORLY ORGANIZED AS IT APPROACHES THE TEXAS COAST. THE CENTER OF TROPICAL STORM ERIN WAS NEAR 26.5N 95.1W AT 16/0000 UTC OR ABOUT 125 NM/235 KM EAST-NORTHEAST OF BROWNSVILLE TEXAS AND ABOUT 170 NM/310 KM SOUTH OF GALVESTON TEXAS. ERIN IS MOVING NORTHWEST NEAR 11 KT. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 35 KT WITH GUSTS TO 45 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1003 MB. PLEASE SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/WTNT25 KNHC OR THE LATEST PUBLIC ADVISORY UNDER MIATCPAT5/WTNT35 KNHC FOR MORE DETAILS. RAINBANDS ASSOCIATED WITH ERIN ARE AFFECTING THE TEXAS COAST. TOTAL RAIN ACCUMULATIONS OF 3 TO 5 INCHES ARE POSSIBLE ALONG THE MIDDLE TEXAS COAST...WITH ISOLATED MAXIMUM AMOUNTS OF 8 INCHES. SOME STRENGTHENING OF ERIN IS POSSIBLE BEFORE SHE MAKES LANDFALL THURSDAY MORNING. THE CENTER OF TROPICAL STORM DEAN WAS NEAR 13.1N 47.9W OR ABOUT 790 NM EAST OF THE LESSER ANTILLES AT 15/2100 UTC MOVING WNW 19 KT. MAXIMUM SUSTAINED WIND SPEEDS ARE 55 KT WITH GUSTS TO 65 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 994 MB. FURTHER STRENGTHENING IS FORECAST DURING THE NEXT 24 HOURS AND DEAN COULD BECOME A HURRICANE LATER TONIGHT OR EARLY THURSDAY. PLEASE SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC OR THE LATEST PUBLIC ADVISORY UNDER MIATCPAT4/WTNT34 KNHC FOR MORE DETAILS. ASSOCIATED MODERATE TO STRONG CONVECTION IS FROM 10N-15N BETWEEN 47W-52W...WITH A TIGHTLY CURVED BAND WRAPPING AROUND THE CENTER. BUOY 41041 NOW TO THE NE OF DEAN HAS BEEN REPORTING 20-30 KT WINDS WITH SEAS UPWARDS OF 15 FT OVER THE LAST FEW HOURS...WHICH IS SLIGHTLY ABOVE THE NORTH ATLANTIC HURRICANE WW3 GUIDANCE. ...TROPICAL WAVES... AN EASTERN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 31W SOUTH OF 19N MOVING WEST NEAR 15 KT. A 1010 MB LOW PRESSURE CENTER IS ALONG THE WAVE NEAR 14N. THIS WAVE CONTINUES TO EXHIBIT A BROAD AREA OF CYCLONIC TURNING IN THE SURROUNDING LOW AND MID CLOUD FIELD...THOUGH SHOWER AND TSTM ACTIVITY REMAINS MINIMAL. A TROPICAL WAVE IS MOVING THROUGH THE LESSER ANTILLES ALONG 60/61W MOVING W 15-20 KT. THIS WAVE CONTINUES TO EXHIBIT AN INVERTED V SHAPE IN THE SURROUNDING LOW AND MID LEVEL CLOUDS. DEEP CONVECTION REMAINS MINIMAL THOUGH A FEW ISOLATED SHOWERS ARE MOVING THROUGH THE WINDWARD ISLANDS. ...THE ITCZ... AXIS IS CENTERED ALONG 12N15W 9N27W 13N43W 9N52W 8N58W. OUTSIDE OF THE ACTIVITY ASSOCIATED WITH T.S. DEAN AS DESCRIBED ABOVE...LITTLE DEEP CONVECTION IS NOTED. HOWEVER...A LARGE REGION OF CLOUDINESS AND EMBEDDED ISOLATED MODERATE CONVECTION IS MOSTLY E OF 20W FROM 6N-18N...WHICH SEEMS ASSOCIATED WITH THE NEXT TROPICAL WAVE ABOUT TO MOVE OFF THE AFRICAN COAST. ANOTHER SMALL REGION OF ISOLATED MODERATE CONVECTION IS S OF THE AXIS FROM 5N-8N BETWEEN 22W-27W. DISCUSSION... THE GULF OF MEXICO... TROPICAL STORM ERIN REMAINS THE FOCUS TONIGHT...WHICH IS PRODUCING NUMEROUS SHOWERS/ISOLATED TSTMS N OF 24N W OF 90W. MORE DETAILS ON ERIN CAN BE FOUND IN THE SPECIAL FEATURE SECTION ABOVE. IN ADDITION...THE SE GULF IS ALSO ACTIVE THIS EVENING WITH NUMEROUS MODERATE/ISOLATED STRONG CONVECTION S OF 27N E OF 90W. LOW LEVEL CONFLUENCE SE OF ERIN IS SPARKING THIS ACTIVITY...WITH FURTHER SUPPORT FROM DIFFLUENT FLOW ALOFT AROUND THE SE PERIPHERY OF AN UPPER RIDGE. CLOUD TOPS ARE BEING STRETCHED TO THE S TOWARDS THE CARIBBEAN WITH UPPER NLY FLOW OVER THIS ACTIVITY. ALL OF THIS MOISTURE EXPECTED TO CONTINUE PUSHING NW OVER THE NEXT COUPLE OF DAYS AS ERIN MOVES INLAND. THE CARIBBEAN SEA... SCATTERED SHOWERS AND TSTMS ARE ALSO AFFECTING THE FAR NW CARIB/YUCATAN CHANNEL THIS EVENING AS DESCRIBED ABOVE IN THE GULF SECTION. OTHERWISE THE CARIBBEAN REMAINS PRETTY QUIET. ASSISTING IN THE TRANQUIL CONDITIONS IS CONFLUENT UPPER FLOW AND DRY MID TO UPPER AIR OVER MUCH OF THE AREA EXCEPT FOR THE NW PORTION...WHERE NE FLOW AROUND RIDGING IS SPREADING ABUNDANT UPPER MOISTURE FROM THE GULF INTO THE AREA. AN INVERTED UPPER TROUGH EXTENDS SSW FROM RINCON PUERTO RICO TO NEAR 12N72W. THIS IS LIKELY ASSISTING IN THE ISOLATED SHOWERS IN THE MONA PASSAGE. TRADES ARE MODERATE AT THE MOMENT BUT THAT IS EXPECTED TO CHANGE LATER IN THE WEEK AND INTO THE WEEKEND AS DEAN NEARS. INTERESTS IN THE LESSER ANTILLES SHOULD MONITOR THE PROGRESS OF DEAN. THE ATLANTIC OCEAN... THE WRN ATLC W OF 72W IS PRETTY QUIET TONIGHT WITH VERY DRY MID TO UPPER AIR BEING ADVECTED SWD THROUGH THE AREA...BY UPPER NLY FLOW AROUND AN UPPER LOW NEAR 28N72W. LIFT AHEAD OF THIS UPPER LOW IS SUPPORTING CLOUDINESS AND A FEW SHOWERS AND TSTMS BETWEEN 62W-71W. IN ADDITION A WEAK 1015 MB SFC LOW IS NEAR 30N69W WHICH HAS A TROUGH EXTENDING SW TO THE SE BAHAMAS NEAR 22N75W. THIS LOW IS EXPECTED TO DISSIPATE OVER THE NEXT DAY OR SO AS RIDGING BUILDING BACK OVER THE WRN ATLC. A MOSTLY BENIGN UPPER LOW IS NOTED NEAR 30N45W. DEEP LAYER RIDGING IS N OF DEAN AND IS EXPECTED TO STRENGTHEN OVERNIGHT...FORCING THE STORM ON MORE OF A WWD COURSE TOMORROW. THE REMAINDER OF THE AREA N OF 20N E OF 55W IS DOMINATED BY FAIR WEATHER AND LIGHT TO MODERATE WINDS S OF A 1031 MB HIGH NEAR 44N31W. THE EXCEPTION REMAINS STRONGER NE WINDS OFF THE COAST OF NW AFRICA WHERE A STRONGER GRADIENT EXISTS BETWEEN THE ATLC RIDGING AND THERMAL TROUGHING OVER LAND. $$ WILLIS