Tropical Weather Discussion
Issued by NWS
Issued by NWS
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517 AXPZ20 KNHC 120905 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Wed Nov 12 2025 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 0600 UTC surface analysis and satellite imagery through 0855 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A 1028 mb high pressure system over the NE Gulf of America continues to support gales with wind speeds to 40 kt across the Gulf of Tehuantepec. Strong to gale- force winds extend downstream the Gulf of Tehuantepec to 09N and west to 103W. This was confirmed by a recent scatterometer satellite pass. Seas are currently peaking around 16 ft (5 M) and rough seas extend south to 05N and west to 107W. Winds and seas will diminish as the high pressure weakens and shift eastward in the next few days, but pulses to gale-force will continue through across the Gulf of Tehuantepec Thu night. Seas will gradually subside, decreasing below 8 ft Fri night. Large NW swell following frontal boundary: A cold front is approaching the far NW corner, and is expected to enter our waters today. The front will then move eastward across the waters north of 20N into Sat. Large NW swell in excess of 12 ft and wind speeds to near gale-force will follow the front over the waters north of 25N from late today into Sat. Seas are forecast to peak around 17 ft Thu. Rough seas will reach south to 10N and the offshore waters of Baja California late Fri into Sat. Winds and seas will diminish Sun. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N84W to 08N98W. The ITCZ stretches from 08N98W to 09N120W to beyond 10N140W. Scattered moderate to isolated strong convection is observed from 06N to 15N and east of 117W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please refer to the Special Features section for additional information on the Gale Warning in the Gulf of Tehuantepec. A 1020 mb high pressure system remains positioned a few hundred miles west of Baja California. The weak pressure gradient supports gentle to locally moderate NW winds and moderate seas across the Baja California offshore waters. Elsewhere outside of the Gulf of Tehuantepec and downstream waters, moderate or weaker winds and slight to moderate seas are prevalent. For the forecast, the gale-force N winds in the Gulf of Tehuantepec will continue to pulse into Thu night. Rough to very rough seas accompany these gales downstream. Winds and seas will gradually diminish through late Fri as the high pressure north of the area weakens and shifts eastward. Farther north, a cold front will move across Baja California and the Gulf of California late Thu through Sat. Expect fresh to strong SW gap winds across the northern Gulf of California ahead of the front late Sat into early Sun. Fresh to strong NW winds and rough seas to 12 ft will follow the front off Baja California late Thu into Sat, before subsiding Sun. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... High pressure north of the region continues to dominate the basin. The tight pressure gradient between the aforementioned ridge and lower pressures in the deep tropics result in fresh to strong N-NE winds in the Guatemala and El Salvador offshore waters, captured by a recent scatterometer satellite pass. Farther west, a strong gap wind event in the Gulf of Tehuantepec is producing seas to 13 ft and fresh to locally strong N winds in the waters off Guatemala beyond 60 nm. The same high pressure system is forcing fresh to strong easterly trade winds and rough seas in the Gulf of Papagayo area. Meanwhile, gentle to moderate southerly breezes and moderate seas in S swell are prevalent elsewhere. A few showers and isolated thunderstorms are affecting the nearshore and offshore waters of Costa Rica, Panama and Colombia. For the forecast, fresh to strong gap winds will pulse each night and morning over the next few days across the Papagayo region as a strong high pressure builds into the NW Caribbean. Offshore of Guatemala, expect rough seas through Fri as gale-force gap wind event continues in the nearby Gulf of Tehuantepec. Elsewhere, moderate or lighter winds and moderate seas will persist into the weekend. ...REMAINDER OF THE AREA... Please see the Special Features section regarding large NW swell and strong to near gale-force winds following a cold front forecast to enter the region today. In the eastern waters, a recent scatterometer satellite pass show that a strong gap wind event in the Gulf of Tehuantepec is supporting fresh to strong NE-E winds north of 05N and east of 107W. Seas in these waters are 8-14 ft. Satellite imagery depict a weak area of low pressure and stationary frontal boundary over the far western waters continue producing a few showers in the region. Moderate to locally fresh southerly winds and rough seas are found north of 23N and west of 130W. Meanwhile, a surface trough along 124W in the trade waters sustains moderate to locally fresh easterly winds and rough seas south of 20N and between 115W and 135W. South of the monsoon trough and ITCZ, moderate to locally fresh southerly winds and moderate to rough seas are present. Elsewhere, weak high pressure dominates and sustains moderate or lighter winds and moderate seas. For the forecast, outside of the area in the Special Features section, the winds and seas associated with the gap wind event will gradually dimish over the next couple of days. The large southerly swell will subside with seas decreasing below 8 ft Fri. Moderate southerly winds and moderate seas will then prevail south of the monsoon trough and ITCZ into the weekend. $$ Delgado