000 AXPZ20 KNHC 261444 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC MON OCT 26 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 1430 UTC. ...SPECIAL FEATURES... TROPICAL STORM OLAF W OF 140W CENTERED NEAR 24.6N 141.5W AT 26/1500 UTC OR 925 NM ENE OF HONOLULU HAWAII AND 812 NM ENE OF HILO HAWAII. ESTIMATED MINIMUM CENTRAL PRESSURE IS 992 MB. MAXIMUM SUSTAINED WIND SPEED IS 50 KT WITH GUSTS TO 60 KT. SEE LATEST CPHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS HFOTCMCP5/WTPA25 PHFO FOR MORE DETAILS. OVER THE DISCUSSION WATERS...SCATTERED MODERATE CONVECTION IS FROM 24N TO 27N W OF 136W. OLAF IS FORECAST TO MOVE NE AND CROSS 140W AS A TROPICAL STORM LATER TODAY...THEN IS FORECAST TO WEAKEN TO A TROPICAL DEPRESSION AS IT REACHES 27.4N 135.2W BY 0000 UTC WED...THEN BECOMING A POST-TROPICAL REMNANT LOW AS IT MOVES TO NEAR 26.9N 134.1W BY 1200 UTC WED...DISSIPATING BY FRI. CURRENTLY SW SWELLS GENERATED BY OLAF ARE MIXING WITH LONG PERIOD NW SWELL ACROSS OUR NW WATERS WITH COMBINED SEAS OF 8-11 FT W OF A LINE FROM 30N122W TO 20N137W. GULF OF TEHUANTEPEC GALE WARNING...UNFORTUNATELY OVERNIGHT SCATTEROMETER DATA MISSED THE GULF AREA HOWEVER MINIMAL GALE FORCE NORTHERLY WINDS ARE LIKELY STILL OCCURRING THIS MORNING IN THE WAKE OF A STRONG COLD FRONT WHICH MOVED BY N OF THE AREA THROUGH THE SW GULF OF MEXICO. STRONG HIGH PRES RIDGING IS BUILDING SOUTHWARD ACROSS EASTERN MEXICO AND THIS RIDGING COMBINED WITH EARLY MORNING NOCTURNAL DRAINAGE FLOW HAS HELPED TO PRODUCE THE STRONG TO GALE FORCE WINDS. SEAS ARE UP TO 12 FT JUST DOWNWIND OF THE GULF. WINDS ARE FORECAST TO DIMINISH BELOW GALE FORCE BY LATE THIS AFTERNOON/EARLY EVENING...THEN 20 KT OR LESS BY TUE EVENING WITH RESIDUAL SEAS SUBSIDING TO LESS THAN 8 FT BY THEN AS WELL. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM 09N84W TO 09N90W TO 07N99W THEN RESUMES FROM 15N103W TO 12N113W TO 14N120W TO LOW PRES NEAR 12N127W TO 08N135W. SCATTERED MODERATE CONVECTION IS FROM 04N TO 10N BETWEEN 79W AND 91W...WITHIN 120 NM SW OF A LINE FROM 08N92W TO 14N102W...FROM 08N TO 13N BETWEEN 109W AND 115W...AND ALSO WITHIN 180-210 NM SE OF THE AXIS W OF 119W. IN ADDITION...SCATTERED MODERATE CONVECTION IS WITHIN 120 NM SW OF THE COAST OF MEXICO BETWEEN 98W AND 101W ON THE SW SIDE OF A LARGE UPPER ANTICYCLONE NEAR 18N96W. ...DISCUSSION... N OF 15N E OF 120W...A FAIRLY WEAK GRADIENT REMAINS IN PLACE OVER THE REGION BETWEEN 1018 MB HIGH PRES CENTERED NEAR 36N128W AND BROAD SURFACE TROUGHING OVER NW MEXICO. THE LATEST SHIP OBSERVATIONS AND SCATTEROMETER DATA INDICATE GENERALLY LIGHT TO MODERATE NW FLOW PERSISTING OFF THE COAST OF BAJA CALIFORNIA AND GULF OF CALIFORNIA. SEAS HAVE SUBSIDED ACROSS THE GULF OF CALIFORNIA TO 2 FT OR LESS W OF 110W...AND 3-5 FT IN SE-S SWELL NEAR THE ENTRANCE TO THE GULF. A WEAK MID/UPPER LEVEL SHORT WAVE TROUGH MOVING EASTWARD ACROSS THE REGION THIS MORNING WILL BE FOLLOWED BY ANOTHER WEAK MID/UPPER TROUGH TUE INTO WED...KEEPING THE RELATIVELY TRANQUIL MARINE CONDITIONS IN PLACE. LOOKING AHEAD...A STRONGER MID/UPPER TROUGH WITH AN ASSOCIATED COLD FRONT WILL APPROACH THE AREA LATE IN THE WEEK. THIS WILL BRING STRONG NORTHERLY FLOW TO THE WATERS NORTH OF GUADALUPE ISLAND...ALONG WITH A NEW ROUND OF LONG PERIOD NW SWELL WITH WAVE HEIGHTS 8 TO 10 FT TO THE BAJA COAST BY LATE THU. S OF 15N E OF 110W...AN UPPER TROUGH IS SWEEPING ACROSS N PORTIONS AND APPROACHING BAJA AND SOUTHERN CALIFORNIA EARLY TONIGHT. WEAK LOW PRES WILL CONTINUE TO OCCASIONALLY FORM ALONG THE MONSOON TROUGH NEAR 90W W OF COSTA RICA...BUT WILL REMAIN ELONGATED MAKING IT DIFFICULT TO DEPICT AS A DISTINCT LOW CENTER. NO SIGNIFICANT DEVELOPMENT IS ANTICIPATED THROUGH THE NEXT 48 HOURS. RESIDUAL SW SWELL IS MAINTAINING SEAS OF 5 TO 8 FT OVER MUCH OF THE AREA. ELSEWHERE...A 1010 MB LOW PRES IS ANALYZED NEAR 11N127W EMBEDDED ALONG THE MONSOON TROUGH. EARLIER SCATTEROMETER DATA INDICATED MODERATE TO FRESH WINDS WITHIN 120 NM ON THE NW SIDE OF THE LOW WHERE RESULTANT SEAS ARE UP TO 8 FT. LITTLE CHANGE IS ANTICIPATED IN THE POSITION OR INTENSITY OF THE LOW PRES THROUGH THE NEXT SEVERAL DAYS WITH A LINGERING PATCH OF FRESH WINDS AND SEAS TO 8 FT PERSISTING THROUGH TUE NIGHT. SEAS WILL INCREASE HOWEVER BY LATE WEEK WITH THE ADDITION OF LONG PERIOD NW SWELL INTO THIS AREA. THE NW SWELL WITH SEAS 8 TO 13 FT WILL ENVELOP MUCH OF THE BROADER REGION NW OF LINE FROM THE OFF BAJA CALIFORNIA NORTE TO 11N140W BY LATE WED. $$ LEWITSKY