000 AXPZ20 KNHC 170906 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SAT OCT 17 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 0730 UTC. ...SPECIAL FEATURES... TROPICAL STORM OLAF WAS CENTERED NEAR 9.5N 128.5W AT 0900 UTC MOVING WEST OR 270 DEGREES AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1003 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. SCATTERED MODERATE TO STRONG CONVECTION WAS WITHIN 120 NM SE SEMICIRCLE AND 60 NM NW SEMICIRCLE. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS ELSEWHERE FROM 08N- 12N BETWEEN 125W-132W. OLAF IS FORECAST TO CONTINUE TO INTENSIFY AS THE SYSTEM MOVES WEST-NORTHWESTWARD...REACHING MINIMAL HURRICANE INTENSITY LATE SUN. PLEASE SEE LATEST FORECAST ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS ON OLAF. GULF OF TEHUANTEPEC...WINDS OF MINIMAL GALE FORCE ARE FUNNELING INTO THE GULF OF TEHUANTEPEC. WINDS WILL REMAIN AT NEAR GALE FORCE OR MINIMAL GALE FORCE OVER THE NEXT COUPLE OF DAYS. MAXIMUM SEAS OF 10-14 FT ARE EXPECTED. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH WAS ANALYZED FROM 14N90W TO 10N98W TO 09N103W TO 10N111W. SCATTERED MODERATE TO STRONG CONVECTION WAS N OF 11N E OF 95W AND FROM 11N-14N BETWEEN 95W-101W. SCATTERED MODERATE CONVECTION WAS FOUND ELSEWHERE S OF THE AXIS TO 04N BETWEEN 83W- 107W. ...DISCUSSION... A COLD FRONT EXTENDS THROUGH 32N130W TO 27N140W. A 1023 MB SUBTROPICAL HIGH PRES SYSTEM CENTERED NW OF THE AREA NEAR 33N147W LIES BEHIND THE FRONT. THE PRESSURE GRADIENT BETWEEN THE HIGH TO THE N AND TROPICAL STORM OLAF TO THE S IS DRIVING MAINLY MODERATE TRADE WINDS. THE COLD FRONT WILL WEAKEN AS IT PULLS E- SE TODAY...DISSIPATING OVERNIGHT TONIGHT. 8-10 FT SEAS IN NW SWELL MAINLY BEHIND THE FRONT WILL CONTINUE TO PROPAGATE SOUTHEASTWARD BUT GRADUALLY SUBSIDE. THE SUBTROPICAL RIDGE WILL BUILD OVER N WATERS ONCE THE FRONT DISSIPATES. THIS WILL HELP EXPAND THE AREA OF 20-33 KT WINDS AROUND TROPICAL STORM OLAF. SW SWELL WITH PERIODS IN THE 19-21 SECOND RANGE WILL PASS GALAPAGOS ISLANDS TODAY...REACH THE PACIFIC COAST S OF MAZATLAN MEXICO OVERNIGHT TONIGHT...AND STRETCH N ALONG THE PACIFIC COAST OF THE BAJA CALIFORNIA PENINSULA AFTER SUNRISE SUN. THIS LONG- PERIOD SWELL COULD MAKE FOR DANGEROUS CONDITIONS ENTERING AND EXITING PORTS AND WILL INCREASE THE THREAT OF RIP CURRENTS. THE SW SWELL IS CONTRIBUTING TO THE 7-9 FT SEAS CURRENTLY FOUND OVER MUCH OF THE AREA S OF 10N BETWEEN 89W AND 129W. THE SWELL W OF 105W WILL SUBSIDE...WITH SEAS LESS THAN 8 FT EXPECTED BY SUN AFTERNOON. A DEVELOPING CENTRAL AMERICAN GYRE WILL HELP MAINTAIN WINDS OF NEAR GALE TO MINIMUM GALE FORCE FOR THE FORECAST PERIOD OVER THE GULF OF TEHUANTEPEC. THIS GYRE WILL HELP INCREASE SW MONSOON FLOW OVER THE EASTERN WATERS AND MAINTAIN SEAS IN THE 7-9 FT RANGE S OF THE GULF OF TEHUANTEPEC TO 04N. THE INCREASED MONSOON FLOW WILL ADVECT ABUNDANT TROPICAL MOISTURE INTO THE EASTERN WATERS AND PORTIONS OF CENTRAL AMERICA AND SOUTHERN MEXICO. THIS WILL LEAD TO ACTIVE WEATHER OVER THIS AREA FOR THE NEXT SEVERAL DAYS. THE GLOBAL MODELS CONTINUE TO HINT THAT THE INTERACTION OF THE GALE FORCE WINDS WITH THE MONSOON TROUGH WILL HELP TO GENERATE A LOW PRESSURE AREA SOUTH OF THE GULF OF TEHUANTEPEC SUN. THIS LOW WILL HAVE THE POTENTIAL TO DEVELOP INTO A TROPICAL CYCLONE NEXT WEEK. REGARDLESS OF TROPICAL CYCLONE DEVELOPMENT...THIS SYNOPTIC SETUP WILL BRING THE POTENTIAL FOR HEAVY RAINFALL AND MAY LEAD TO FLASH FLOODING AND DANGEROUS MUDSLIDES OVER PORTIONS OF CENTRAL AMERICA AND SOUTHERN MEXICO. $$ SCHAUER/AL