000 AXPZ20 KNHC 210322 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC MON AUG 21 2006 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0315 UTC. ...SPECIAL FEATURES... TS HECTOR NEAR 20.9N 134.6W 1000 MB AT 0300 UTC AUG 21 MOVING NW OR 310 DEG AT 8 KT. MAXIMUM SUSTAINED WINDS 40 KT GUSTS 50 KT. SATELLITE IMAGERY SHOWS AN INTERMITTENT EXPOSED LOW LEVEL CENTER TO THE W OF DISORGANIZED CONVECTION WITH A STRATOCUMULUS FIELD OVER MOST OF THE WRN SEMICIRCLE. CURRENTLY SCATTERED MODERATE TO STRONG CONVECTION IS NOTED WITHIN 90 NM OVER THE E SEMICIRCLE. RAPID WEAKENING IS EXPECTED TO CONTINUE TONIGHT AS HECTOR ENCOUNTERS COLDER WATER...VERTICAL WIND SHEAR AND MORE A MORE STABLE ENVIRONMENT. HECTOR WILL LIKELY WEAKEN TO A TD ON MON AND DISSIPATE BY TUE. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. WEAK LOW PRES IS NEAR 10N ALONG A TROPICAL WAVE LYING N TO S ALONG 100W. THE ESTIMATED PRES IS 1008 MB AND MOVING W 5 KT. BROAD CYCLONIC ROTATION CONTINUES WITH INTERMITTENT ATTEMPTS AT BANDING...CURRENTLY VERY DISORGANIZED CONVECTION. AN UPPER ANTICYCLONE TO ITS NW NEAR 23N110W RIDGES SE ALONG THE CENTRAL AMERICAN PACIFIC COAST TO NEAR 14N100W WITH UPPER DIFFLUENCE OVER NRN EXTENSION OF THE TROPICAL WAVE. MENTION OF POSSIBLE TROPICAL CYCLONE DEVELOPMENT CONTINUED ON TEXT AND GRAPHICS. ...TROPICAL WAVES... A TROPICAL WAVE N OF 4N ALONG 83W IS ESTIMATED TO BE MOVING W AT 12 KT. CONVECTION IS ISOLATED AT BEAT ALONG THE WAVE AXIS IN THE E PAC...BUT A LARGE AREA OF CYCLONIC TURNING AND SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED NEAR 16N80W. A TROPICAL WAVE ALONG 124.5W FROM 3N TO 15N IS MOVING W AT AN ESTIMATED 12 KT. ALTHOUGH BROAD CYCLONIC TURNING IS NOTED ONLY SCATTERED SHOWERS AND A FEW TSTMS ACCOMPANY THE WAVE WITHIN 60 NM OF ITS AXIS FROM 6N TO 12N. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 10N84W 12N100W 8N113W 15N136W 12N140W. SCATTERED MODERATE ISOLATED STRONG FROM 7N TO 15N BETWEEN 94W AND 109W AND WITHIN 150 NM EITHER SIDE OF LINE 9N111W 9N128W AND LINE 12N135W 12N140W. ...DISCUSSION... A NEGATIVE TILT SHORTWAVE TROUGH LIES ALONG 32N127W 30N127W. A SECOND SHORTWAVE IS STATIONARY N TO S ALONG 32N118W THROUGH AN UPPER CYCLONE AT 18N118W AND CONTINUING S TO A BASE AT 10N116W. VERY DRY AIR IS NOTED ALONG THE TROUGH AXIS FROM 27N TO 32N. AN ANTICYCLONE IS CENTER NEAR 20N125W AND RIDGES N TO A GENTLE CREST ALONG POINTS 25N133W 28N125W 28N119W...AND EFFECTIVELY SEPARATES THE TWO UPPER TROUGHS. THE TROUGH TO THE W APPEARS TO BE ERODING THE NW PERIPHERY OF THE RIDGE. ANOTHER ANTICYCLONE IS QUASI STATIONARY AREA NEAR 18N144W RIDGING E TO A CREST JUST W OF THE TS HECTOR AT 17N137W. A SMALL UPPER CYCLONE IS ESTIMATED NEAR 20N98W WITH AN UPPER TROUGH EXTENDING ENE TO ANOTHER UPPER CYCLONE OVER THE YUCATAN CHANNEL AT 22N86W. UPPER MOISTURE...ORIGINATING FROM ITCZ CONVECTION THROUGHOUT THE DISCUSSION AREA AND FROM TS HECTOR...IS NOTED ELSEWHERE SE OF LINE 22N140W 29N121W. MODERATE DRY AIR UPPER IS NOTED NW OF THE SAME LINE. AT THE SURFACE...A RIDGE EXTENDS SE ALONG 32N130W TO 20N116W WITH NW WINDS SURGING TO 20 KT AND SEAS TO 8 FT OVER THE WATERS N OF 25N ALONG THE W COAST OF THE BAJA PENINSULA. $$ NELSON