Eastern Pacific Tropical Weather Discussion
388 AXPZ20 KNHC 202105 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Tue Oct 20 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 2000 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: High pressure settled over Mexico will continue to funnel northerly gap winds of gale-force into the Gulf of Tehuantepec through tonight. Seas in these waters are rough. Winds will diminish to strong Wed, but will increase to gales again Thu night into Fri night. Gale Warning South of Southern Mexico (Invest EP94): A low- pressure system located a few hundred miles south of the Gulf of Tehuantepec is producing a large area of showers and thunderstorms that are gradually becoming better organized, and a tropical depression is forecast to form during the next day or so. This system is expected to move westward to west- northwestward at 5 to 10 kt during the next few days, remaining well offshore of southern Mexico. A large area of fresh to strong winds and rough seas surround this low center, and these winds and seas are expected to increase over the next day or so. A Gale Warning has been issued as a result, for Wed into Thu. There is a high chance of tropical formation of this low within the next 48 hours. Please read the latest High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N86W to 04N106W. The ITCZ stretches from 04N106W to 09N112W and from 06N130W to 03N140W. Scattered moderate to isolated strong convection is noted from 00N to 15N E of 105W and from 01N to 08N and W of 130W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for information on the Gale Warning in the Gulf of Tehuantepec. Elsewhere, weak low pressure centered E of the Revillagigedo Islands is leading to moderate NW winds through the islands. Otherwise, light to gentle winds and moderate seas prevail, except for slight seas in the Gulf of California. For the forecast, high pressure settled over Mexico will continue to funnel northerly gap winds of gale-force into the Gulf of Tehuantepec into tonight. Seas in these waters are rough. Winds will diminish to strong by Wed, but will increase to gales again Thu night through Fri night. A low- pressure system located a few hundred miles south of the Gulf of Tehuantepec is producing a large area of showers and thunderstorms that are gradually becoming better organized, and a tropical depression is forecast to form during the next day or so. This system is expected to move westward to west- northwestward at 5 to 10 kt during the next few days, remaining well offshore of southern Mexico. There is a high chance of tropical formation of this low within the next 48 hours. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Rough seas coming from gale-force gap winds in the Gulf of Tehuantepec continue to impact waters well offshore Guatemala. Otherwise, gentle to moderate winds and moderate seas prevail. For the forecast, rough seas well offshore Guatemala deriving from gap winds in the Gulf of Tehuantepec will decay tonight. Winds will pulse nightly to fresh in the Papagayo region. Moderate or weaker winds and moderate seas will prevail elsewhere. ...REMAINDER OF THE AREA... See Special Features section above for information on a Gale Warning issued in association with a low pressure system that has a potential for tropical development. Elsewhere, fresh NW winds and rough seas are increasing behind a cold front that extends from 30N138W to 38N136W. Moderate or weaker winds and moderate seas dominate the remainder of the basin. For the forecast, as the cold front moves SE tonight, fresh to strong winds and very rough seas will impact waters N of 26N through Wed, with rough seas reaching as far south as 20N Thu. A low- pressure system located a few hundred miles south of the Gulf of Tehuantepec is producing a large area of showers and thunderstorms that are gradually becoming better organized, and a tropical depression is forecast to form during the next day or so. This system is expected to move westward to west- northwestward at 5 to 10 kt during the next few days, remaining well offshore of southern Mexico. A large area of fresh to strong winds and rough seas surround this low center, and these winds and seas are expected to increase over the next day or so. A Gale Warning has been issued as a result, for Wed into Thu. There is a high chance of tropical formation of this low within the next 48 hours.