Eastern Pacific Tropical Weather Discussion
460 AXPZ20 KNHC 122124 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Mon Oct 12 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Hurricane Simon is centered near 20.2N 106.8W at 2100 UTC, moving west-northwest at 3 kt. Estimated minimum central pressure is 969 mb. Maximum sustained wind speed is 85 kt with gusts to 105 kt. Peak seas are near 20 ft. Numerous moderate to strong convection is within 60 nm of the center. Scattered to numerous moderate and isolated strong convection is elsewhere from 18N to 22N between 105W and 109W. Simon is moving slowly to the west-northwest and is forecast to continue moving slowly toward the northwest and affect Las Tres marias through late Tue before beginning to veer toward the north-northeast, and move inland across Sinaloa on Thu night. Gradual weakening is expected during the next 24 hour due to vertical wind shear, but conditions could become favorable for restrengthening late Tue through Thu. Simon is expected to produce rainfall totals of 5 to 10 inches across coastal west-central Mexico with isolated maximum amounts of 15 inches over the state of Sinaloa by Thursday. This rainfall will produce life- threatening flooding and mudslides or worsen any on- going flooding, 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, as well as the southern Gulf of California. These swells are likely to cause large and powerful surf and life- threatening 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. Invest EP93: The axis of a tropical wave is near 94W, north of 02N, moving westward at 5-10 kt. A 1008 mb low pressure is analyzed near 08N94W in association with the wave. This system is producing a large area of showers and thunderstorms, with scattered to numerous moderate to strong convection noted from 04N to 14N between 90W and 98W. This system is gradually becoming better defined, and environmental conditions are forecast to be conducive for further development. A tropical depression is expected to form well south of southern Mexico in the next two days while the system moves generally west-northwestward at around 10 kt. There is a high chance for tropical cyclone development through next 7 days. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10.5N76W to 10.5N84W to 1008 mb low pres near 08N94W to 12.5N102W, then resumes near 17N114W to 09N127W to beyond 08N140W. Scattered to numerous moderate to strong convection is noted from 01S to 09.5N E of 88W. Scattered moderate convection is noted from 01N to 07.5N between 98W and 115W, and within 75 nm of the monsoon trough between 114W and 140W. Scattered moderate isolated strong convection is noted S of 03N between 127W and 138W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for information on Hurricane Simon. A cold front has stalled from the far northern Gulf of California along 31.5N southwestward across Baja Norte to beyond 24.5N120W. Fresh SW winds and moderate seas to 5 ft are impacting the northern Gulf of California ahead of the front. Gentle to locally moderate winds, and slight to moderate seas, are elsewhere over the Gulf, except for seas to 5 ft in S swell from Simon across the entrance. Mostly moderate to locally fresh NW to N prevail across the Baja Norte waters behind the front, while light to gentle SW to W winds are south of the front across the remaining Baja waters, becoming moderate NW south of Cabo San Lucas and into Simon. Seas are 6 to 9 ft in NW swell across the Baja offshore waters this afternoon, while seas generated from Simon are producing seas of 8 ft and greater south of Baja between 110W and the SW Mexican coast. Fresh northerly gap winds are in the Gulf of Tehuantepec. Elsewhere, moderate or weaker winds and moderate to rough seas in SW swell prevail. For the forecast, Hurricane Simon is expected to move slowly west-northwestward and impact Las Tres Marias through Tue, reaching near 20.5N 107.0W tonight, near 20.9N 107.5W Tue afternoon, near 21.2N 107.7W Tue night, near 21.5N 107.7W Wed afternoon, near 22.2N 107.4W Wed night, and inland near 24.2N 106.6W by Fri afternoon. A cold front moving across the northern waters will drift southeastward and gradually dissipate through Wed. Rough seas in NW swell west of Baja California will gradually diminish tonight through early Wed. Elsewhere, a broad area of low pressure has formed several hundred miles south southwest of the coast of Guatemala, accompanied by numerous shower and thunderstorm activity. This system is gradually becoming better defined, and environmental conditions are forecast to be conducive for further development. A tropical depression is expected to form well south of southern Mexico in the next two days while the system moves generally west- northwestward at around 10 kt. There is a high chance for tropical cyclone development through next 7 days. Regardless of development, expect an increase in winds and seas across the waters off southern Mexico by midweek. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh easterly winds extend offshore from the Papagayo region to beyond 90W, where seas are 6 to 7 ft. A broad cyclonic circulation has developed associated with the tropical wave along 94W, Invest EP93 described above, and is producing scattered to numerous convection that extends into the offshore waters of Guatemala and Nicaragua. Moderate to fresh SW to S winds are just W of the offshore waters S of 09N and near 90W. Gentle to moderate SW to S winds and moderate seas to 7 ft in SW swell are elsewhere S of 08N. These monsoonal winds are forcing widespread moderate to strong convection across the waters N of 03.5N and E of 85W to Colombia, and are impacting most of the near and offshore waters there. For the forecast, a weak pressure gradient will support moderate or lighter winds, and moderate seas dominated by SW swell across much of the forecast waters through the end of the week. Numerous showers and thunderstorms are expected to remain active across the waters E of 85W through Tue then diminish significantly by early Wed. Moderate to fresh NE to E winds across the Papagayo region today will gradually weaken through mid week as the tropical wave along 94W shifts westward away from the area. ...REMAINDER OF THE AREA... A cold front is moving across the NE waters from Baja California Norte to 21N128W is followed by moderate to fresh northerly winds and rough seas of 7 to 10 ft in NW swell N of 20N. Light to gentle winds and seas of 6 to 8 ft in merging NW and SW swell generally prevail elsewhere S of 20N W of 120W, except for moderate SE to S winds near the equator. For the forecast, the cold front will drift southeastward across the waters E of 130W through late Tue while gradually dissipating. Large SW swell will affect the waters S of the Equator and west of 105W over the next couple of days, followed by another pulse of large S-SW swell arriving into the waters W of 100W Wed night.