Tropical Weather Discussion

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Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Thu May 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. ...TROPICAL WAVES... A tropical wave is near 97.5W from offshore Oaxaca southward is moving W at 5 to 10 kt. Scattered moderate convection is noted from 02N to 15N between 93W and 100W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N74.5W to 10N84W to 08.5N114W to 05.5N123W to 06N126W. The ITCZ extends from 06N126W to 08N133W to beyond 06N140W. Scattered moderate to strong convection is present from 03N to 09N E of 92W, including the offshore waters of Panama and Colombia. Scattered moderate to strong convection is noted from 02N to 10N E of 97W and from 02.5N to 14N between 97W and 115W. Scattered moderate convection is noted from 04N to 11N W of 115W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weak pressure gradient prevails over the region, leading to mainly light to gentle winds. Moderate to locally fresh NW winds are impacting waters near and offshore of Cabo San Lucas as modest ridging builds in from the N Pacific. Seas are moderate, 4 to 6 ft in NW swell across the offshore waters, except to 7 ft NW of Isla Guadalupe, and slight in the Gulf of California. Scattered showers and isolated thunderstorms are moving westward across the outer waters of the Gulf of Tehuantepec, behind a tropical wave. For the forecast, a weak pressure gradient will dominate through late week, leading to moderate seas and moderate or weaker winds. By late weekend and early next week, ridging building SW toward the region will lead to moderate to locally fresh winds offshore Baja California, along with a slight increase in seas. ....OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong NE to E gap winds and 6 to 8 ft seas continue across the Papagayo region, with moderate N gap winds in the Gulf of Panama extending southward to near 06N. Elsewhere, active convection continues across the waters E of 90W, that is described in the ITCZ/Monsoon Trough section above, N of the Monsoon Trough, light to gentle winds and 3 to 5 ft seas dominate, with gentle to moderate mainly southerly winds and 4 to 6 ft seas to the south. For the forecast, fresh gap winds will pulse nightly in the Papagayo region. Otherwise, gentle to moderate winds and moderate seas in southerly swell will prevail into the weekend. ...REMAINDER OF THE AREA... A surface trough that had been W of Baja California has dissipated, and associated shower activity has also dissipated. Farther south, a 1008 mb low pressure is near the monsoon trough around 10N115.5W. Convection near this low is described in the ITCZ/Monsoon Trough section above. A broad surface ridge extends southeastward from a 1033 mb high near 37N146W across 30N140W then southward to the ITCZ. This feature is maintaining moderate to fresh NE winds and seas of 7 to 10 ft north of the ITCZ and west of 125W. Gentle to moderate N to NE to E winds with 5 to 7 ft in mixed NW and S swell continue north of the ITCZ east of 125W. South of the ITCZ, gentle to moderate S to SE winds and seas at 5 to 8 ft in moderate southerly swell prevail. For the forecast, the aforementioned ridge will gradually weaken while shifting southwestward through the end of the week. This will allow winds and seas north of the ITCZ to subside to between gentle to moderate, and 5 to 6 ft, respectively, by this weekend. Little change is expected S of the ITCZ into the weekend. Active convection is expected to continue near the monsoon trough and ITCZ between 100W and 120W through Sat.