000 AXPZ20 KNHC 042142 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SAT OCT 04 2008 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2045 UTC. ...SPECIAL FEATURES... TROPICAL STORM MARIE AT 18.5N 122.2 W AT 04/2100 UTC OR ABOUT 850 NM W-SW OF SRN TIP OF BAJA CALIFORNIA DRIFTING N OR 360 DEG AT 2 KT. ESTIMATED MINIMUM CENTRAL PRES 992 MB AND MAXIMUM SUSTAINED WIND SPEED 55 GUSTS TO 65 KT. REFER TO LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC AND INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPEP4/ WTPZ34 KNHC FOR MORE DETAILS. MARIE HAS LOST SOME OF ITS DEEP CONVECTION AND TOPS HAVE WARMED INDICATING WEAKENING STAGE HAS BEGUN. ADVERSE UPPER AND LOWER LEVEL ENVIRONMENT INDICATE THE DOWNWARD CYCLE FOR MARIE SHOULD MAINTAIN THE DOWNWARD FINAL TREND. MARIE EXPECTED TO CONTINUE GRADUALLY LOSING ITS PUNCH AND ORGANIZATION TILL ITS DEMISE. TROPICAL DEPRESSION FIFTEEN-E AT 14.2N 100.3W AT 04/2100 UTC OR ABOUT 190 NM S OF ACAPULCO MEXICO DRIFTING W AT 4 KT. ESTIMATED MINIMUM CENTRAL PRES 1006 MB AND MAXIMUM SUSTAINED WIND SPEED 30 GUSTS TO 40 KT. REFER TO LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC AND INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPEP5/WTPZ35 KNHC FOR MORE DETAILS. T.D. 15-E FOUGHT GALLANT BATTLE AGAINST MODERATE EASTERLY WIND SHEAR AND SURVIVED. IT IS NOW APPROACHING A MORE FAVORABLE ENVIRONMENT CONDUCIVE TO STRENGTHENING AS UPPER FLOW BECOMES DIFFLUENT. SYSTEM FORECAST TO BECOME TROPICAL STORM SUN. LOW PRES CENTER 1009 MB AT 10N88W DRIFTING W SHOWS IMPRESSIVE CLOUD PATTERN DESPITE MODERATE NORTHEASTERLY WIND SHEAR ALOFT. DOWNSTREAM ENVIRONMENT EXPECTED TO BECOME MORE FAVORABLE...SO POSSIBILITY OF GRADUAL INTENSIFICATION LIKELY WITHIN NEXT 36-48 HRS. LOW LEVEL CLOUD CENTER PRESENTLY REMAINS AT THE E EDGE OF CONVECTION WHILE BANDS ARE KEPT IN W SIDE DUE TO MODERATE EASTERLY WIND SHEAR. ...TROPICAL WAVES... NONE. ...ITCZ... ITCZ AXIS ALONG 13N120W TO 09N132W TO 08N140W. SCATTERED MODERATE CONVECTION WITHIN 120 NM N OF AXIS W OF 130W. ...DISCUSSION... UPPER LEVELS... ELONGATED RIDGE AXIS STRETCH FROM SW N ATLC ACROSS YUCATAN PENINSULA INTO E PAC WITH SECOND ANTICYCLONE AT 17N113W. WEAK TROUGH SADDLES RIDGE ALONG 105W. DIFFLUENT FLOW CAUSED BY THIS TROUGH AND ATLC RIDGE EXPECTED TO PROPEL T.D. 15-E INTO BECOMING TROPICAL STORM BY SUN. AT THE SAME TIME...TROPICAL STORM MARIE IS MOVING AWAY FROM ITS FAVORABLE ENVIRONMENT ALOFT CURTAILING ITS OUTFLOW AND UNABLE TO MAINTAIN ITS INTENSITY. FURTHER W...UPPER LEVEL TROUGH FROM NRN BAJA CALIFORNIA TO CYCLONE ALOFT AT 18N133W THEN CONTINUE TO 23N140W CAUSING MODERATE TO STRONG SUBSIDING AIR MASS N OF 16N W OF 124W. THIS DRY AND STABLE AIR MASS ALSO HELP IN ACCELERATING TROPICAL STORM MARIE DEMISE. ELSEWHERE AT THE SURFACE... STRONG WINDS BLOWING ACROSS ISTHMUS OF TEHUANTEPEC INTO E PAC HAVE BEEN SUPPORTED BY WEAK SURFACE LOW PRES 1011 MB OVER E COAST OF YUCATAN PENINSULA. LOW PRES EXPECTED TO DRIFT DISSIPATE WITHIN NEXT 24 HRS RELAXING PRES GRADIENT OVER SRN GULF OF MEXICO AND DIMINISHING TEHUANTEPEC WINDS WITHIN NEXT 30 HRS. COLD FRONT FROM 32N121W TO 23N135W AND ITS ATTENDANT 1025 MB HIGH PRES CENTER PRODUCING LARGE LONG PERIOD SWELLS SPILLING SE INTO E PAC BASIN EVENTUALLY MERGING WITH SWELLS PRODUCED BY TROPICAL STORM MARIE CAUSING VERY CONFUSED SEAS N OF 22N W OF 120W. SWELL CONTINUE EXTENDING S THROUGH FORECAST PERIOD. SIGNIFICANT LONG PERIOD CROSS-EQUATORIAL S SWELL CONTINUE S OF 15N W OF 130W WITH SEAS UP TO 12 FT. NOAA WW3 SOLUTION INDICATE SUBSIDING SEAS WITHIN 24-30 HRS BUT THEN BECOME REINFORCED BY NORTHERLY SWELL MENTIONED IN ABOVE PARAGRAPH. $$ WALLY BARNES