ZCZC MIATCDEP2 ALL TTAA00 KNHC DDHHMM TROPICAL STORM GREG DISCUSSION NUMBER 16 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072011 800 AM PDT SAT AUG 20 2011 BURSTS OF DEEP CONVECTION CONTINUE TO FLARE CLOSE TO THE CENTER OF A WEAKENING GREG. SATELLITE INTENSITY ESTIMATES FROM TAFB AND SAB ARE 45 AND 35 KT...RESPECTIVELY...WHILE THE FINAL T NUMBERS CAME IN AT 35 AND 30 KT. THE INITIAL INTENSITY HAS BEEN LOWERED TO 35 KT...ESSENTIALLY AN AVERAGE OF THE DVORAK GUIDANCE. THE INITIAL MOTION IS 275/09...AND LITTLE CHANGE HAS BEEN MADE TO THE PREVIOUS FORECAST TRACK. GREG WILL CONTINUE TO BE STEERED ON A SLIGHTLY NORTH OF DUE WEST TRACK TODAY BY THE NORTHEAST PACIFIC SUBTROPICAL HIGH. THE HIGH WILL BE WEAKENING SLIGHTLY OVER THE NEXT COUPLE OF DAYS AS A MID TO UPPER LEVEL TROUGH DIGS OFF THE WEST COAST. THIS IS EXPECTED TO HAVE LITTLE IMPACT ON GREG...WHICH WILL BECOME INCREASINGLY SHALLOW AND SHOULD BE STEERED TO THE WEST SOUTHWEST BY THE HIGH. THE FORECAST TRACK IS ESSENTIALLY DOWN THE MIDDLE OF THE GUIDANCE ENVELOPE. GREG IS WEAKENING OVER COOL WATERS AND IS INGESTING STABLE AIR FROM THE NORTH. AN ASCAT PASS FROM LAST EVENING DETECTED WINDS OF 30 TO 35 MAINLY WITHIN THE NORTH SEMICIRCLE...AND THESE DATA HAVE BEEN INCORPORATED INTO THE WIND RADII AND INTENSITY. SSTS ARE BARELY OVER 23C AND WILL CHANGE LITTLE OVER THE NEXT COUPLE OF DAYS. AS A RESULT...GREG SHOULD CONTINUE TO STEADILY WEAKEN AND GRADUALLY SPIN DOWN INTO A REMNANT LOW PRESSURE SYSTEM BY 24 HOURS OR SO. FORECAST POSITIONS AND MAX WINDS INIT 20/1500Z 19.7N 120.0W 35 KT 40 MPH 12H 21/0000Z 19.8N 121.4W 30 KT 35 MPH 24H 21/1200Z 19.7N 123.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 36H 22/0000Z 19.4N 124.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 48H 22/1200Z 19.0N 125.8W 20 KT 25 MPH...POST-TROP/REMNT LOW 72H 23/1200Z 18.0N 128.1W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 24/1200Z...DISSIPATED $$ FORECASTER AVILA/WROE NNNN
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