000 AXPZ20 KNHC 172107 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2100 UTC. ...SPECIAL FEATURES... TROPICAL STORM OLAF IS CENTERED NEAR 9.2N 130.5W AT 2100 UTC MOVING WEST OR 265 DEGREES AT 11 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 999 MB. MAXIMUM SUSTAINED WIND SPEED IS 50 KT WITH GUSTS TO 60 KT. SCATTERED STRONG CONVECTION WAS NOTED WITHIN 90 NM OF CENTER. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS NOTED ELSEWHERE FROM 05N TO 11N BETWEEN 126W AND 132W. OLAF IS FORECAST TO CONTINUE TO INTENSIFY AS IT MOVES IN A GENERAL WESTWARD MOTION OVER THE NEXT COUPLE OF DAYS...AND IS FORECAST TO REACH HURRICANE STRENGTH SUNDAY. 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 CONTINUE TO FUNNEL THROUGH THE CHIVELA PASS AND 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 WITH THIS EVENT. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 14N92W TO 09N108W TO 09N119W. SCATTERED MODERATE ISOLATED STRONG CONVECTION COVERS A LARGE AREA OVER FORECAST WATERS N OF 09N BETWEEN 87W AND 102W. ...DISCUSSION... HIGH PRESSURE OF 1017 MB CENTERED NEAR 27N131W. A WEAK COLD FRONT IS ANALYZED FROM NEAR 30N130W TO 27N140W. THE PRESSURE GRADIENT BETWEEN THE HIGH TO THE N AND TROPICAL STORM OLAF TO THE S IS DRIVING MAINLY MODERATE TRADE WINDS OVER MUCH OF THE WESTERN HALF OF THE FORECAST AREA OUTSIDE THE CIRCULATION OF OLAF. THE COLD FRONT WILL CONTINUE TO WEAKEN AS MOVES E THROUGH THIS EVENING...AND IS EXPECTED TO DISSIPATE BY EARLY SUN MORNING. SEAS TO 9 FT IN NW SWELL CURRENTLY PREVAIL OVER THE WATERS NW OF A LINE FROM 30N132W TO 23N140W. THIS SWELL WILL PROPAGATE SLOWLY SE WHILE SUBSIDING THE NEXT COUPLE OF DAYS. BY MON AFTERNOON...COMBINED SEAS ASSOCIATED TO THIS SWELL WILL SUBSIDE BELOW 8 FT. HIGH PRESSURE WILL BUILD IN THE WAKE OF THE FRONT OVER THE NORTHERN WATERS. 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 REACH THE PACIFIC COAST S OF MAZATLAN MEXICO OVERNIGHT...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. A CENTRAL AMERICAN GYRE WILL HELP MAINTAIN WINDS OF NEAR GALE TO MINIMUM GALE FORCE FOR THE FORECAST PERIOD OVER THE GULF OF TEHUANTEPEC. THE TROPICAL WAVE THAT HAS PROPAGATED INTO THE REGION HAS BEEN ABSORBED INTO THIS LARGER SCALE GYRE. AS TYPICAL WITH CENTRAL AMERICAN GYRES...THE MONSOON TROUGH HAS BEEN LIFTED FURTHER NORTHWARD AND SW MONSOONAL FLOW HAS INCREASED. THIS ENHANCED MONSOON FLOW CONTINUES TO ADVECT ABUNDANT TROPICAL MOISTURE INTO THE EASTERN WATERS AND PORTIONS OF CENTRAL AMERICA AND SOUTHERN MEXICO WHICH WILL MAINTAIN THE POTENTIAL FOR ACTIVE WEATHER OVER THIS AREA FOR THE NEXT FEW DAYS. GLOBAL MODELS CONTINUE TO SUGGEST THAT THE INTERACTION OF THE GALE FORCE WINDS WITH THE MONSOON TROUGH WILL HELP TO GENERATE A LOW PRESSURE CENTER...WITHIN THIS LARGER SCALE GYRE...S OF THE GULF OF TEHUANTEPEC WHICH WILL HAVE THE POTENTIAL TO DEVELOP INTO A TROPICAL CYCLONE NEXT WEEK. REGARDLESS OF TROPICAL CYCLONE FORMATION...THIS SYNOPTIC SETUP WILL BRING THE POTENTIAL FOR HEAVY RAINFALL WHICH MAY LEAD TO FLASH FLOODING AND DANGEROUS MUDSLIDES OVER PORTIONS OF CENTRAL AMERICA AND SOUTHERN MEXICO THROUGH EARLY NEXT WEEK. $$ AL