000 AXPZ20 KNHC 271605 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC TUE OCT 27 2015 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1545 UTC. ...SPECIAL FEATURES... POST-TROPICAL CYCLONE OLAF IS CENTERED NEAR 26.7N 135.1W AT 1500 UTC. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1000 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. THE 1500 UTC ADVISORY IS THE LAST ADVISORY ISSUED BY THE NATIONAL HURRICANE CENTER. PLEASE SEE LATEST HIGH SEAS FORECASTS ISSUED BY THE NATIONAL WEATHER SERVICE...UNDER AWIPS HEADER MIAHSFEP2... NFDHSFEPI AND WMO HEADER FZPN01 KWBC FOR ADDITIONAL INFORMATION ON THE POST-TROPICAL CYCLONE OLAF. STRONG UPPER LEVEL SW WIND SHEAR ASSOCIATED WITH AN UPPER LEVEL TROUGH JUST TO THE W OLAF HAS DISPLACED THE REMAINDER OF THE SMALL AREA OF CONVECTION EARLIER NOTED WELL TO THE NORTHEAST OF THE EXPOSED LOW LEVEL CENTER...ELONGATED FROM SW TO NE. THE REMAINDER OF THIS CONVECTION IS NOTED AS SCATTERED MODERATE N OF 28N BETWEEN 125W-132W. THE UNFAVORABLE UPPER LEVEL CONDITIONS ARE EXPECTED TO PERSIST ACROSS THE REGION FOR THE NEXT 48 HOURS...AND CONTINUE TO WEAKEN THE POST-TROPICAL CYCLONE AS IT MOVES NE. IT IS FORECAST TO WEAKEN FURTHER TO 30 KT WITH GUSTS TO 40 KT EARLY THIS EVENING NEAR 26.9N 134.4W AS IT BECOMES INVOLVED WITH AN APPROACHING COLD FRONT. THE COLD FRONT WILL REACH FROM 32N134W TO 23N140W THIS EVENING...THEN STALL AND DISSIPATE THROUGH LATE WED AS HIGH PRES BUILDS TO THE NORTH. THE STEERING FLOW SOUTH OF THE RIDGE WILL ALLOW THE REMNANT LOW OF OLAF TO SHIFT WESTWARD STARTING WED. LARGE NORTHWEST SWELL GENERATED BEHIND THE COLD FRONT WILL MERGE WITH THE SWELL AND WAVES FROM OLAF IN THE NEXT 48 HOURS TO MAINTAIN HIGH SEAS ACROSS NW PORTIONS IN THE 10-15 FT RANGE. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM 10N85W TO 11N95W TO LOW PRES NEAR 15N103W 1010 MB TO 12N110W 16N120W TO LOW PRES NEAR 13.5N126W 1009 MB TO 09N132W TO 08N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 300 NM S OF TROUGH BETWEEN 110W-121W...FROM 05N TO 08N BETWEEN 96W-100W...AND WITHIN 60 NM OF LINE FROM 06N88W TO 06N92W. SCATTERED MODERATE CONVECTION IS WITHIN 300 NM S OF TROUGH BETWEEN 110W-121W...FROM 05N TO 08N BETWEEN 96W-100W...AND ALSO WITHIN 60 NM S OF TROUGH BETWEEN 129W AND 130W. ...DISCUSSION... N OF 15N E OF 120W...THE LATEST IN SERIES OF WEAK MID/UPPER LEVEL SHORT WAVE TROUGHS CONTINUE TO MOVE EASTWARD ACROSS THE BAJA CALIFORNIA PENINSULA AND GULF OF CALIFORNIA THIS MORNING...ENHANCING SCATTERED MODERATE CONVECTION NEAR A 1009 MB LOW PRES AREA ALONG THE MONSOON TROUGH FARTHER TO THE SOUTH. AT THE SURFACE...WEAK 1016 MB HIGH PRES CENTERED NEAR 26N124W IS MAINTAINING A WEAK PRESSURE PATTERN ACROSS THE REGION...RESULTING IN GENERALLY LIGHT TO GENTLE BREEZES OVER MOST OF THE AREA. LITTLE CHANGE IS EXPECTED UNTIL MID WEEK WHEN LONG PERIOD NW SWELL START IMPACTING THE AREA...WITH SEAS TO 8 FT REACHING THE COAST OF BAJA CALIFORNIA NORTE BY LATE WED. LOOKING AHEAD...A LONG WAVE DEEP LAYER TROUGH BECOMES MORE AMPLIFIED ACROSS THE WESTERN UNITED STATES LATE IN THE WEEK...SUPPORTING PUSH OF FRESH TO STRONG NORTHERLY WINDS INTO THE WATERS OFF BAJA CALIFORNIA NORTE AND AROUND GUADALUPE ISLAND. GULF OF TEHUANTEPEC...ASCAT SCATTEROMETER DATA FROM LAST NIGHT REVEALED N-NE 20 TO 30 KT GAP WINDS PUSHING INTO THE GULF OF TEHUANTEPEC...BETWEEN WEAK HIGH PRES OVER THE SW GULF OF MEXICO AND LOWER PRES FARTHER SOUTH IN THE DEEP TROPICS. SINCE THEN... THE GRADIENT HAS SLACKEN SOME...AND SO THESE WINDS HAVE DIMINISHED TO 20-25 KT. THESE WINDS WILL DIMINISH FURTHER TO 15- 20 KT THIS AFTERNOON. A PLUME OF 9 FT SEAS EXTENDING DOWNSTREAM OF THE GULF OF TEHUANTEPEC TO 13N96.5W WILL SUBSIDE TO BELOW 8 FT OVER THE NEXT 06 HOURS. S OF 15N E OF 110W...MODERATE TO FRESH SW FLOW ON THE SOUTH SIDE OF 1009 MB LOW PRES CENTERED ALONG THE MONSOON TROUGH 104W IS SUPPORTING AREAS OF MODERATE TO STRONG CONVECTION WITHIN 120 NM SOUTH OF THE MONSOON TROUGH...AIDED IN PART BY A PASSING MID/UPPER LEVEL SHORT WAVE TROUGH TO THE NORTHWEST. THE FRESH SW FLOW IS ALSO INTERACTING WITH LINGERING SW SWELL TO CREATE AN AREA OF 8 FT SEAS SOUTH OF THE LOW PRES. THE WINDS AND SEAS WILL DIMINISH LATER TODAY AS THE LOW WEAKENS. LOOKING AHEAD TO LATE IN THE WEEK...VARIOUS WAVE MODELS INDICATE THAT SW SWELL WILL MINGLE WITH INVADING NW SWELL TO SUPPORT CONFUSED SEAS 8 TO 9 FT IN THE AREA SOUTH OF CLIPPERTON ISLAND FROM 06N TO 10N BETWEEN 105W AND 110W. ELSEWHERE...A PAIR OF 1009 MB LOW PRES AREAS ARE ANALYZED ALONG THE MONSOON TROUGH...ONE NEAR 15N103W AND THE OTHER NEAR 13.5N126W. SCATTEROMETER DATA FROM 06 UTC INDICATED MODERATE TO FRESH WINDS WITHIN 120 NM ON THE NW SIDE OF THE EASTERNMOST LOW WHERE RESULTANT SEAS ARE UP TO 8 FT. THESE LOW PRES WILL EFFECTIVELY MERGE INTO A SINGLE ALBEIT ELONGATED LOW PRES AREA THROUGH TODAY. OTHERWISE LITTLE CHANGE IS ANTICIPATED IN THE INTENSITY OF THE LOW PRES THROUGH THE NEXT SEVERAL DAYS AS IT DRIFTS NW...WITH A LINGERING PATCH OF FRESH WINDS AND SEAS TO 8 FT PERSISTING THROUGH LATE TODAY. SEAS WILL INCREASE HOWEVER BY LATE WEEK WITH THE ADDITION OF LONG PERIOD NW SWELL INTO THIS AREA. $$ NR/AGUIRRE