Eastern Pacific Tropical Weather Discussion
843 AXPZ20 KNHC 211559 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Fri Aug 21 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 FEATURE... Central East Pacific (EP91): An area of low pressure located several hundred miles south of the southern tip of the Baja California Peninsula is producing disorganized showers and thunderstorms. Environmental conditions appear favorable for gradual development, and a tropical depression is likely to form this weekend or early next week while the system moves west- northwestward or northwestward at 5 to 10 mph. This system has a medium chance for tropical cyclone formation through 48 hrs, and a high chance through 7 days. Please refer to the latest NHC Tropical Weather Outlook at website: https://www.nhc.noaa.gov/text/MIATWOEP.shtml for more details on these systems. ...TROPICAL WAVES... A tropical wave is moving over eastern portions of the Tropical Pacific basin with axis along 90W, N of 03N, moving westward at 15 to 20 kt. Scattered moderate convection is along the wave axis from 05N to 11N between 96W and 110W. The axis of a tropical wave is near 104W, N of 05N, moving westward at 10 to 15 kt. Scattered moderate to isolated strong convection is noted from 04N to 17N between 96W and 110W. This system is moving west-northwestward and could become a tropical depression over the weekend or early next week before it interacts, or possibly merges with, a disturbance to its west (EP91). This system has a low chance for tropical cyclone formation through 48 hrs, and a medium chance through 7 days. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N84W to 10N104W to 06N125W to 08N136W. Aside from the convection related to the tropical waves described above, scattered moderate to isolated strong convection is observed from 05N to 07N between 78W and 81W, and from 04N to 12N W of 128W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge dominates the offshore forecast waters of Baja California producing gentle to moderate NW to N winds with moderate seas. Light to gentle winds and slight seas prevail across the Gulf of California. High pressure over east-central Mexico and a surface trough moving across the Bay of Campeche support fresh to strong N gap winds across the Gulf of Tehunatepec and downwind to about 14N. Seas are up to 8 ft with these winds. Light to gentle winds and moderate seas are noted across the remainder of the Mexican offshore waters. Fresh to strong E to SE are just off the offshore waters 10N to 13N between 97W and 103W behind a tropical wave located along 104W. For the forecast, fresh northerly gap winds will continue to pulse to strong speeds over the Gulf of Tehuantepec during the overnight into the early morning hours through Sun night, with seas occasionally building to rough. A ridge will continue to dominate the offshore forecast waters of Baja California this weekend supporting mainly gentle to moderate winds. Southerly wind flow will return to the Gulf of California Sat night and become fresh to locally strong Sun. Winds and seas are expected to build across the outer offshore waters of southwestern Mexico into early next week in association with a developing area of low pressure moving west-northwestward or northwestward and just outside of the offshore waters. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Latest satellite scatterometer data shows fresh to strong NE to E gap winds across the Papagayo region and downwind to near 90W, where seas are 6 to 8 ft. Moderate or weaker winds are found elsewhere, with moderate seas in S swell. For the forecast, high pressure will persist over the eastern Gulf of America and northwestern Caribbean into early next week, leading to fresh NE to E gap winds pulsing to strong speeds over the Papagayo region each evening and night. Moderate to fresh winds extending well downwind of Papagayo will impact the outer waters offshore of El Salvador and Guatemala through at least early next week. South of the monsoon trough, winds will gradually diminish and remain light to gentle through the weekend. Mainly moderate seas will prevail away from the Gulf of Papagayo through the next several days. ...REMAINDER OF THE AREA... Please see the Special Features section and the Tropical Waves section above for information on systems that have the potential for tropical cyclone formation, and any associated convection currently present leading to higher winds and seas. High pressure across the NE Pacific extends a ridge southeastward into the regional waters to offshore of Baja California. Fresh easterly winds and seas to 7 ft are noted in the periphery of Tropical Depression Two-C in the Central Pacific basin are impacting the waters between 15N to 20N and W of 138W. Elsewhere, moderate to locally fresh winds are found N of 15N and W of 125W, where seas are 5 to 7 ft. Moderate or weaker winds and moderate seas in mixed swell prevail elsewhere. For the forecast, regardless of tropical cyclone development, the features described above will bring increasing winds and seas to the waters south of 25N, as they move south of the current ridge in place. Away from these features, little change is expected in marine weather through the next several days, except for the rough seas over the southern waters, which are forecast to fully subside by the start of the weekend.