Eastern Pacific Tropical Weather Discussion
663 AXPZ20 KNHC 110913 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sun Oct 11 2026 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 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 Simon is centered near 18.7N 105.2W at 11/0900 UTC, moving north-northwest at 5 kt. Estimated minimum central pressure is 930 mb. Maximum sustained wind speed is 135 kt with gusts to 165 kt. Peak seas are near 30 ft. Numerous moderate to scattered strong convection is within 60 nm of center. Scattered moderate to isolated strong convection is elsewhere from 15N to 21N between 101W and 111W. The hurricane has turned north- northwest at about 5 kt. This motion is expected to continue today, bringing the core of the hurricane along the coast of southwestern Mexico. Some weakening should start soon due to the hurricane's close proximity to land. However, Simon is still expected to be an extremely dangerous hurricane as it passes near southwestern Mexico today. Catastrophic wind and life-threatening storm surge impacts are likely along a portion of the west- central coast of Mexico. Simon is expected to produce rainfall totals of 10 to 20 inches over portions of southwestern Mexico. This rainfall will produce life- threatening flooding and mudslides, especially in areas of steep terrain. Swells generated by Simon will affect portions of the coast of southwestern and west- central Mexico during the next few days. These swells are likely to cause life- threatening surf and rip current conditions. Please consult products from your local weather office. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest Simon NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... The axis of a tropical wave is near 88W, north of 02N. The wave is producing disorganized showers and thunderstorms. Environmental conditions are expected to be conducive for gradual development, and a tropical depression is likely to form well south of southern Mexico by the middle or latter half of next week as the system moves generally west- northwestward at around 10 mph. There is a low chance for tropical cyclone development in the next 48 hours, and a high chance for development in the next 7 days. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N85W to 08N92W to 12N101W, then resumes near 16N120W to beyond 09N140W. Scattered moderate and isolated strong convection is noted from 00N to 12N between 80W and 100W. Scattered moderate convection is noted from 00N to 05N between 110W and 130W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for information on Major Hurricane Simon. Post- Tropical Cyclone Rachel has moved north of the area. Fresh to near- gale force winds on the southern side of the system are impacting the northern Gulf of California. Wind flow around the system is also forcing fresh to strong gap winds over portions of the central Gulf of California as well as fresh to strong winds over the waters west of Baja California Norte. Rough to very rough seas generated by Rachel continue to impact the waters west of the Baja California peninsula. Elsewhere, moderate or weaker winds and slight to moderate seas prevail. For the forecast, Hurricane Simon is near 18.7N 105.2W at 2 AM PDT, and is moving north-northwest at 5 kt. Maximum sustained winds are 135 kt with gusts to 165 kt, and the minimum central pressure is 930 mb. Simon will move to 19.5N 105.4W this afternoon, 20.5N 105.7W Mon morning, 21.2N 106.0W Mon afternoon, weaken to a tropical storm near 22.0N 106.3W Tue morning, inland to 23.2N 106.2W Tue afternoon, and dissipate Wed morning. Post- Tropical Cyclone Rachel has moved north of the area. Fresh to strong winds will linger over the northern Gulf of California through early Mon. Winds and seas lingering west of the Baja California peninsula will gradually diminish through early this week. Elsewhere, disorganized showers and thunderstorms over the far eastern East Pacific are associated with a tropical wave. Environmental conditions are expected to be conducive for gradual development, and a tropical depression is likely to form well south of southern Mexico by the middle or latter half of next week as the system moves generally west-northwestward at around 10 mph. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh winds and moderate seas prevail over the Papagayo region. Light to gentle winds and moderate seas are elsewhere N of 04N. Gentle to moderate southerly winds and moderate seas in SW swell prevail S of 04N. For the forecast, a weak pressure gradient will support moderate or lighter winds and moderate seas across much of the forecast waters through the middle of next week. Moderate to fresh NE to E winds are expected in the Papagayo region tonight and Mon. ...REMAINDER OF THE AREA... Please see the Special Features section above for information on Major Hurricane Simon. Moderate to fresh winds and rough seas are noted N of 20N W of 115W. Elsewhere, moderate or lighter winds and moderate seas prevail. For the forecast, as Rachel moves over the southwest United States, a cold front is forecast to extend across the northern forecast waters today. Fresh N to NE winds and rough seas, in long period northerly swell, will follow the front forecast to reach from the northern Baja California to near 22N125W on Mon while gradually dissipating. Large SW swell will continue to affect the waters S of the Equator and west of 105W over the next couple of days.