000 AXPZ20 KNHC 210957 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SUN AUG 21 2011 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0900 UTC. ...ITCZ/MONSOON TROUGH... MONSOON TROUGH FROM 09N84W TO 15N96W TO 15N103W TO 1011 MB LOW PRES AT 12N106W TO 14N114W RESUMES FROM 15N123W TO 10N140W. SCATTERED MODERATE CONVECTION WITHIN 90 NM OF TROUGH BETWEEN 107W AND 114W. SCATTERED MODERATE TO STRONG CONVECTION N OF 13N BETWEEN 93W AND 97W. ...DISCUSSION... TROPICAL DEPRESSION GREG NEAR 20.2N 121.9W AT 21/0900 UTC MOVING WNW AT 7 KT. MAXIMUM SUSTAINED WIND 30 GUSTS TO 40 KT WITH MINIMUM CENTRAL PRESSURE OF 1008 MB. GREG CONTINUES TO SLOWLY WEAKEN AS IT MOVES INTO AN AREA OF COOLER SEA SURFACE TEMPS. IT IS EXPECTED TO BECOME A POST-TROPICAL REMNANT LOW WITHIN THE NEXT 12-24 HOURS. DEEP CONVECTION HAS DECREASED TO ONLY A SMALL CLUSTER OF CELLS NEAR THE CENTER. DRY LOW/MID LEVEL AIR MASS PREVAILS OVER MOST OF THE BASIN DUE TO MODERATE TO STRONG SUBSIDENCE N OF 15N W OF 122W WITH MOISTURE ASSOCIATED WITH T.D. GREG THE ONLY EXCEPTION. ANTICYCLONIC FLOW OVER REMAINDER OF BASIN WITH E TO SE FLOW ALOFT IS STRONG ENOUGH TO CURTAIL ORGANIZED DEEP CONVECTION ALONG THE MONSOON TROUGH AND THE WEAK SURFACE LOW EMBEDDED IN THE TROUGH NEAR 12N106W. WINDS AND SEAS ASSOCIATED WITH T.D. GREG ARE EXPECTED TO DIMINISH BELOW ADVISORY LEVELS WITHIN THE NEXT 36-48 HOURS. GLOBAL MODEL GUIDANCE HAS BACKED OFF ON THE STRENGTH OF THE SW MONSOON FLOW S OF THE TROUGH AXIS...AND AS A RESULT EXPECT ONLY MINOR INCREASE IN SEAS TO AROUND 8-9 FT SE OF THE EMBEDDED AREA OF LOW PRES NEAR 12N106W....WHICH IS EXPECTED TO DRIFT NNW NEXT TWO DAYS. LONG PERIOD CROSS EQUATORIAL SWELLS 8-9 FT WILL SPREAD JUST N OF THE EQUATOR INTO THE E PAC BETWEEN 97W AND 115W THROUGH MON. $$ MUNDELL