Eastern Pacific Tropical Weather Discussion
121 AXPZ20 KNHC 081601 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Thu Oct 8 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... Tropical Storm Simon is centered near 15.4N 103.3W at 08/1500 UTC, moving west at 4 kt. Estimated minimum central pressure is 995 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Peak seas are near 15 ft. Numerous moderate to scattered strong convection is observed from 14N to 18N between 99W and 105W. A slow west to west-northwest motion is expected through tonight, followed by a turn toward the north-northwest or north on Friday and Saturday. On the forecast track, Simon is expected to approach the coast of southwestern and west-central Mexico late Saturday. Rapid strengthening is forecast, and Simon is expected to become a hurricane later today and a very dangerous category 4 hurricane before it reaches the coast of Mexico. Simon is expected to produce rainfall totals of 8 to 15 inches over portions of southwestern Mexico, with isolated maximum totals between 15 and 25 inches possible across portions of Michoacan, Colima and Jalisco through Sunday. This rainfall may 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 Storm Rachel is centered near 22.1N 124.2W at 08/1500 UTC, moving west-northwest at 6 kt. Estimated minimum central pressure is 985 mb. Maximum sustained wind speed is 60 kt with gusts to 75 kt. Peak seas are near 24 ft. Scattered moderate convection is within 120 nm of center. Rachel is moving toward the west-northwest. This general motion is expected to continue over the next day, before a sharp turn to the northeast, along with an increase in forward speed, occurs on Saturday. On the forecast track the center of Rachel is expected to approach the northern portion of Baja California on late Saturday. Gradual weakening is expected over the next few days, but Rachel is still expected to be at tropical storm strength when it approaches northern Baja California. Swells partly generated by Rachel will build along the coast of Southern California and northern Baja California through the weekend. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. Interests in extreme northern Baja California, northern Gulf of California, and southern California should monitor the progress of Rachel. Tropical Storm Watches could be required for a portion of this area by tonight. 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 Rachel NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N86W to 14N97W, then resumes S of T.S. Rachel near 13N120W to beyond 11N140W. In addition to the convection associated with Rachel and Simon, scattered moderate to isolated strong convection can be found from 00N to 10N E of 110W, and from 00N to 11N W of 110W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for information on Tropical Storm Simon offshore of southern Mexico. Away from Tropical Storm Simon, a weak pressure gradient dominates the remainder of the Mexican offshore waters, supporting moderate or weaker winds and slight to moderate seas. For the forecast, Tropical Storm Simon will strengthen to a hurricane near 15.5N 104.1W this evening, move to 16.1N 104.9W Fri morning, 16.9N 105.1W Fri evening, 17.6N 105.1W Sat morning, 18.7N 105.1W Sat evening, and inland to 19.7N 105.1W Sun morning. Simon will move inland near 22.2N 105.6W early Mon. Meanwhile, Rachel will move to 22.1N 124.3W this afternoon, 22.5N 125.0W Fri morning, 22.9N 124.7W Fri afternoon, 24.0N 122.8W Sat morning. Rachel should reach the offshore zones off of Baja California Norte on Sat as it accelerates to the NE. Finally, the system is forecast to move across Baja California Norte early Sun just south of the California-Mexico border and inland over early Mon. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate southerly winds and seas of 5 to 7 ft are found between Ecuador and the Galapagos Islands. Elsewhere, a weak pressure gradient persists across the offshore waters of Central America and Colombia, supporting light to gentle winds and moderate seas. For the forecast, long-period southerly swell will produce moderate to locally rough seas between Ecuador and the Galapagos Islands through tonight. Elsewhere, a weak high pressure north of the Caribbean will support moderate or lighter winds and moderate seas across much of the forecast waters through at the middle of next week. Looking ahead, an area of low pressure is forecast to form south of the coast of Guatemala early next week. Environmental conditions appear conducive for some gradual development of this system thereafter, and a tropical depression could form as it moves generally west-northwestward at around 10 kt. This system has a medium chance of tropical cyclone formation in the next 7 days. ...REMAINDER OF THE AREA... Please see the Special Features section above for information on Tropical Storm Rachel located over the NE waters. Outside of the influence of Tropical Storm Rachel, high pressure located well N of area extends a ridge over the NW waters supporting moderate or weaker winds and moderate seas. Rough seas generated by Rachel currently dominate the area from 17N to 28N between 118W and 130W. For the forecast, Tropical Storm Rachel will move to 22.4N 124.9W this evening, 22.7N 125.1W Fri morning, 23.4N 123.9W Fri evening, 25.1N 121.4W Sat morning, 28.4N 118.3W Sat evening, and inland to 32.8N 115.3W Sun morning. Rachel will weaken to a tropical depression while moving inland near 42.4N 110.2W early Mon. Additionally, the large SW swell will continue to affect roughly the waters S of the Equator and west of 105W. Meanwhile, fresh to strong northerly winds and rough seas behind a frontal system will affect the northern waters starting Fri and continue into Sun.