000 AXPZ20 KNHC 270946 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0830 UTC. ...SPECIAL FEATURES... A WEAKENING TROPICAL STORM OLAF CONTINUES TO MOVE NORTHEASTWARD ACROSS NW PORTIONS OF THE DISCUSSION AREA TONIGHT...CENTERED NEAR 26.4N 136.1W AT 0900 UTC. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1000 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. STRONG UPPER LEVEL SW WIND SHEAR ASSOCIATED WITH AN UPPER LEVEL TROUGH CONTINUES TO IMPACT OLAF...AND IS SHEARING OR DISPLACING THE DIMINISHING CONVECTION WELL TO THE NORTHEAST OF THE EXPOSED LOW LEVEL CENTER...ELONGATED FROM SW TO NE. SCATTERED MODERATE CONVECTION IS NOTED FROM 27N TO 28N BETWEEN 130W AND 134W. THE UNFAVORABLE UPPER LEVEL CONDITIONS ARE EXPECTED TO PERSIST ACROSS THE REGION FOR THE NEXT 24 TO 48 HOURS...AND CONTINUE TO WEAKEN OLAF...AS IT MOVES NE AND GRADUALLY WEAKEN TO A TROPICAL DEPRESSION STORM NEAR 27.0N 134.6W BY 18 UTC TODAY. OLAF BECOMES INVOLVED WITH AN APPROACHING COLD FRONT LATE TODAY...WHERE IT IS EXPECTED TO WEAKEN FURTHER TO A 30 KT POST-TROPICAL REMNANT LOW NEAR 27.0N 133.7W WITHIN 24 HOURS. 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 EXTENDS FROM 09.5N85W TO 10N95W TO LOW PRES 1009 MB NEAR 14.5N104W TO 12N110W TO 15N120W TO LOW PRES 1009 MB NEAR 13N126W TO 09N133W TO 10N140W. SCATTERED MODERATE CONVECTION IS NOTED WITHIN 120 NM S OF AXIS BETWEEN 95W AND 102W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS NOTED WITHIN 90 NM N OF AXIS BETWEEN 102W AND 105W. SCATTERED MODERATE TO STRONG CONVECTION IS NOTED WITHIN 90 NM N OF AXIS BETWEEN 125W AND 129W. ...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...AN ASCAT SATELLITE PASS FROM 04 UTC INDICATED 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. THE GRADIENT WILL LOOSEN THROUGH TODAY...ALLOWING THE STRONG GAP WIND FLOW TO DIMINISH 20 KT OR LESS BY LATE TODAY. SIMILARLY A PLUME OF 8 TO 10 FT SEAS EXTENDING DOWNSTREAM OF THE GULF OF TEHUANTEPEC TO 13N96.5W WILL SUBSIDE TO BELOW 8 FT OVER THE NEXT 12 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 NEAR 15N123.5W AND 13N127W. 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. $$ CHRISTENSEN