000 AXPZ20 KNHC 250952 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SUN OCT 25 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... HURRICANE OLAF CONTINUES TO CHURN WEST OF 140W...AND WAS LOCATED NEAR 21.2N 143.8W AT 0900 UTC. MAXIMUM SUSTAINED WINDS 80 KT GUSTS TO 100 KT. OLAF IS EXPECTED TO MOVE NORTHEASTWARD OUT AHEAD OF A COLD FRONT APPROACHING IT FROM THE NW...AND WILL MOVE INTO NW PORTIONS OF THE LOCAL DISCUSSION AREA BETWEEN 24 AND 36 HOURS AS A WEAKENING TROPICAL STORM. INTERACTION WITH THE FRONTAL BOUNDARY AND A WEAKENING TROPICAL STORM MAY WEAKEN OLAF MORE QUICKLY AFTER 48 HOURS...AND THE CPHC FORECAST THEN MOVES OLAF BACK TO THE WEST...EMBEDDED IN THE LOW LEVEL FLOW ALONG THE LEADING EDGE OF THE FRONT. CURRENTLY...SW SWELLS GENERATED BY OLAF ARE COMBINING WITH LONGER PERIOD NW SWELL TO GENERATE SEAS OF 8 TO 11 FT ACROSS THE W CENTRAL AND NW WATERS OF THE DISCUSSION AREA. SEE LATEST CPHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS HFOTCMCP5/WTPA25 KNHC FOR MORE DETAILS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 08N82W TO 07N90W TO 08N97W...WHERE IT REMAINS FRACTURED...THEN RESUMES FROM 15N105W TO 12N117W TO LOW PRES 1011 MB NEAR 12N127W TO 07N132W TO 09N140W. SCATTERED MODERATE CONVECTION IS NOTED WITHIN 60 NM N OF AXIS E OF 87W. SCATTERED MODERATE TO STRONG CONVECTION IS NOTED WITHIN 120 NM S OF AXIS BETWEEN 90W AND 95W. SCATTERED MODERATE CONVECTION IS NOTED WITHIN 60 NM EITHER SIDE OF AXIS BETWEEN 120W AND 130W. ...DISCUSSION... N OF 15N E OF 120W...A FAIRLY WEAK GRADIENT IS AGAIN IN PLACE OVER THE REGION BETWEEN WEAKENING HIGH PRES CENTERED WEST OF THE AREA...AND TROUGHING ALONG THE EAST COAST OF THE GULF OF CALIFORNIA. FRESH TO STRONG NW WINDS ALONG THE GULF OF CALIFORNIA HAVE SUBSEQUENTLY DIMINISHED AS OBSERVED BY A 05 UTC ASCAT SATELLITE PASS. A PAIR OF ALTIMETER SATELLITE PASSES INDICATED SEAS ARE STILL REACHING 8 FT WELL WEST OF THE CENTRAL BAJA CALIFORNIA PENINSULA...LIKELY DUE TO A MIX OF NW AND SE SWELL. WAVE MODELS INDICATE THIS AREA OF SWELL WILL DECAY TO BELOW 8 FT LATER TODAY. FARTHER SOUTH...A 03 UTC ASCAT PASS ALONG WITH COASTAL OBSERVATIONS INDICATED FRESH WEST WINDS FUNNELING ALONG THE COAST OF OAXACA NEAR PUERTO ANGEL. THIS WILL LIKELY DIMINISH THROUGH THE MORNING. A SHARP UPPER TROUGH EXTENDS ACROSS THE REGION...FROM N CENTRAL MEXICO TO ACROSS THE SOUTHERN TIP OF THE BAJA CALIFORNIA PENINSULA TO SW OF CLARION ISLAND. DRY AIR ACCOMPANIES THE UPPER TROUGH...AND THE REGION IS VIRTUALLY CLOUD FREE NORTH OF 20N. A WEAK LOWER LEVEL DISTURBANCE CONTINUES ALONG THE MONSOON TROUGH FARTHER SOUTH...WITH A FEW THUNDERSTORMS NOTED EARLIER NEAR 16N108W...BUT THESE HAVE SINCE DISSIPATED. LOOKING AHEAD...GLOBAL MODELS INDICATE A COLD FRONT WILL APPROACH THE REGION BY LATE WEEK...ACCOMPANIED BY NW SWELL AND STRONG NW WINDS WEST OF GUADALUPE ISLAND. GULF OF TEHUANTEPEC...A COLD FRONT ASSOCIATED WITH DEEP LOW PRES OVER THE NORTHERN GULF OF MEXICO WILL PUSH SOUTH OVER THE WESTERN GULF OF MEXICO AND THROUGH THE ISTHMUS OF TEHUANTEPEC TODAY...BRINGING STRONG NORTHERLY GAP FLOW INTO THE GULF OF TEHUANTEPEC LATE TODAY. THE STRONG GAP WINDS WILL PERSIST THROUGH MONDAY NIGHT/EARLY TUESDAY MORNING WITH THE STRONGEST WINDS OVERNIGHT TONIGHT. SEAS WILL BUILD AS HIGH AS 10 FT BY EARLY MONDAY. S OF 15N E OF 110W...SCATTERED MODERATE TO STRONG SHOWERS AND THUNDERSTORMS ARE ONGOING SOUTH AND ALONG THE MONSOON TROUGH BETWEEN 90W AND 95W...AHEAD OF THE UPPER TROUGH APPROACHING THE AREA FROM THE NW. WEAK LOW PRES IS OCCASIONALLY FORMING ALONG THE MONSOON TROUGH NEAR 90W WEST OF COSTA RICA...BUT TYPICALLY BECOMES ELONGATED ALONG THE TROUGH TO DEPICT AS A DISTINCT LOW CENTER. NO SIGNIFICANT DEVELOPMENT IS ANTICIPATED OVER THE NEXT 48 HOURS. RESIDUAL SW SWELL IS MAINTAINING SEAS OF 5 TO 7 FT OVER MUCH OF THE AREA. ELSEWHERE...A STATIONARY 1011 MB LOW PRES IS ANALYZED NEAR 11N127W ALONG THE MONSOON TROUGH. ASCAT SATELLITE PASSES INDICATE FRESH CYCLONIC WINDS AROUND THIS LOW...TYPICALLY COINCIDENT WITH SCATTERED SHOWERS AND THUNDERSTORMS WITHIN 150 NM. NO SIGNIFICANT DEVELOPMENT OR MOVEMENT IS ANTICIPATED OVER THE NEXT SEVERAL DAYS. GLOBAL MODELS INDICATE THIS LOW PRES WILL STILL BE IN PLACE LATE THIS WEEK. SEAS OF 8 TO 10 FT CAN BE EXPECTED NEAR THE LOW CENTER AT THAT TIME DUE TO LOCAL MODERATE TO FRESH WINDS AROUND THE LOW AND LONG PERIOD NW SWELL MOVING INTO THE AREA. $$ CHRISTENSEN