Tropical Weather Discussion

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Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURE... Central East Pacific (EP91): A trough 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 before it interacts, or possibly merges with, the disturbance to its east. 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 91W, N of 03N, moving westward at 15 to 20 kt. Scattered moderate convection is along the wave axis from 05N to 12N between 90W and 95W. A broad area of low pressure is along a tropical wave with axis near 105W. 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, the disturbance to its west (EP91). Scattered moderate to isolated strong convection is noted from 05N to 17N between 95W and 112W. 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 10N105W to 06N135W. The ITCZ continues from 06N135W to 08N140W. 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 112W. ...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, with the exception of moderate to locally fresh winds in the vicinity of Cabo San Lucas. Light to gentle winds and slight seas prevail across the Gulf of California. High pressure over east-central Mexico, combined with a surface trough moving across the Bay of Campeche, supports fresh to strong N gap winds across the Gulf of Tehuantepec 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 noted just off the offshore waters from 10N to 13N between 100W and 105W behind a tropical wave located along 105W. 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 8 ft. 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 over the north and central parts of the Gulf on 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 and just outside of the offshore waters. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Recent satellite scatterometer data show fresh to strong NE to E gap winds across the Papagayo region and downwind to near 89W, 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, gentle to locally moderate winds will persist this weekend into early next week. 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. High pressure across the NE Pacific extends a ridge southeastward into the regional waters to offshore of Baja California. A surface trough is analyzed over the NW corner of the forecast region and runs from 28N139W to beyond 26N140W. Moderate to fresh NE to E winds are noted near the northern end of the trough axis due to the pressure gradient between the trough and high pressure to the N. Fresh easterly winds and seas to 7 ft in the periphery of Tropical Depression Two-C in the Central Pacific basin are impacting the waters between 15N to 19N and W of 138W based on scatterometer data. Elsewhere, moderate to locally fresh winds are found south of about 07N between 100W and 120W with moderate to locally rough seas. Moderate or weaker winds and moderate seas in mixed swell prevail elsewhere. For the forecast, regardless of tropical cyclone development, the features described above are forecast to bring increasing winds and seas roughly across the waters S of 20N between 100W and 120W this weekend. Little change is expected in the marine conditions elsewhere. Looking ahead, another area of low pressure is expected to develop well south of the southern tip of the Baja California Peninsula during the middle portion of next week. Some slow development is expected thereafter while the system moves generally west- northwestward. This system has a low chance for tropical cyclone formation through 7 days.