000 AXPZ20 KNHC 170300 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Thu Dec 17 2020 Tropical Weather Discussion for the eastern Pacific Ocean from the Equator to 32N, east of 140W. The following information is based on satellite imagery, weather observations, radar, and meteorological analysis. Based on 0000 UTC surface analysis and satellite imagery through 0300 UTC. ...SPECIAL FEATURES... Gulf of Tehunatepec Gale Warning: Gale-force winds in the Tehuantepec area will continue through Friday morning. Strong northerly winds associated with a cold front in the western Gulf of Mexico will funnel into the Gulf of Tehuantepec, with seas building to 12-14 ft. Winds are expected to diminish below gale force on Fri. Please read the latest NWS High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N78W across Panama to 06N92W to 07N99W. The ITCZ continues from 07N99W to 09N122W to beyond 08N140W. Scattered moderate convection is noted from 10N to 15N between 116W and 125W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge dominates the offshore forecast waters of Baja California. The pressure gradient between the ridge and lower pressures over mainland Mexico is resulting in moderate to fresh northerly winds west of the Baja California peninsula. Large long period NW swell propagating across this area is supporting seas to 8-10 ft, which will slowly subside by Fri. A weakening cold front will push into northern Baja California Thu evening and reach Punta Eugenia Fri morning. Moderate to fresh northerly winds will develop Thurs night and Fri morning in the wake of the front. Gulf of California: Fresh NW to N winds will prevail in the Gulf of California through Thu. A weakening cold front will enter the Gulf Thu night and Fri, with winds expected to increase slightly in association with the front. Even after the gale-force winds cease in the Gulf of Tehuantepec, strong northerly winds are expected to continue through the weekend, and could become gale-force once again early next week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Fresh to occasionally strong NE to E winds will pulse at night in the Papagayo region Thu through Mon as high pressure builds over the western Caribbean. Offshore seas for Guatemala and El Salvador will increase Thu through Fri night from swell generated by gale-force winds in Tehuantepec. Elsewhere, gentle to moderate S-SW winds will prevail south of the monsoon trough with mainly gentle to moderate N-NE winds north of the trough axis. REMAINDER OF THE AREA... A cold front is approaching the NW part of the forecast area, which is causing high pressure located near 30N131W to weaken. A ridge extends southeastward from the high across the northern forecast waters to near the Revillagigedo Islands. The pressure gradient between the ridge and lower pressures in the vicinity of the ITCZ will continue to support a large area of fresh trade winds, with the strongest trades expected south of the high, between 125W and 140W. Seas are currently 9 to 11 ft in long- period NW swell. Winds and seas will gradually diminish across the entire area through Thu as the approaching cold front pushes south of 30N. The front will move southward and weaken around 27N through Fri. Winds will increase to fresh behind the dying front on Fri between 120W and 140W. $$ Mundell