000 AXPZ20 KNHC 220930 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sun Nov 22 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: The pressure gradient between a high pressure ridge over the eastern slopes of the Sierra Madre Orientales and the eastern Pacific monsoon trough continues to support gale force northerly winds across the Tehuantepec region tonight. Fresh to strong N to NE winds extend well offshore from Tehuantepec to near 12N96W. Peak seas to 13 ft prevail downwind of the Gulf in the vicinity of 14.5N95W. Associated seas to 8 ft and greater extend well downwind of the outer edge of the offshore waters near 11.5N97W. This long-lived gale event has already peaked in intensity, as the ridge is beginning to slowly weaken across the Gulf of Mexico. However, gale force winds are expected to last through Mon night, while winds diminish slightly each afternoon. Please read the latest NWS High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. ...TROPICAL WAVES... The axis of a tropical wave is repositioned to along 88W N of 03N, moving west at 10 to 15 kt. Overnight scatterometer data showed a weak low pressure center near 09.5N86W that is helping to force active convection across the waters of Costa Rica. Scattered moderate to strong convection is from 06N to 11.5N between 84W and 91W and extends across portions of Central America and into the SW Caribbean Sea. The axis of a tropical wave is near 111W-112W, from 03N to 19N, moving west at 15 kt. Scattered moderate isolated strong convection is noted near the wave axis from 08N to 12N between 105W and 115W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 11N75W to 09N81W to low pres near 09.5N86W 1009 mb to 08N96W to 10N107W to 09N113W. The ITCZ continues from 09N113W to beyond 08N140W. Scattered moderate to strong convection is noted from 06N to 11.5N between 84W and 91W. Scattered moderate isolated strong convection is noted from 08N to 12N between 105W and 115W, and within 120 nm N of the ITCZ between 115W and 133W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A Gale Warning remains in effect for the Gulf of Tehuantepec. Please see the Special Features section above for details. Elsewhwere, a broadening ridge extends southward across the Baja California offshore waters, extending from a 1026 mb high near 38N133W. The pressure gradient between this area of high pressure and a surface trough along the Gulf of California is supporting generally moderate northerly winds across the waters off the coast of Baja California. Gentle to moderate winds prevail elsewhere south of 21N. Wave heights are 5-7 ft in long- period northwest swell across the waters west of Baja California, with 4-6 ft seas prevailing elsewhere. Moderate to locally fresh northerly winds prevail across the central and southern portions of the Gulf of California, where seas are 3-5 ft. These conditions will persist through Sun morning then decrease gradually Sun afternoon through Mon. High pressure will build south-southeastward across the offshore waters and gradually shift westward through the remainder of the weekend. This will produce generally moderate winds across the Baja offshore waters north of 21N through Sun, with seas of 5-6 ft. Strong northerly winds developing off the California coast Sun night and Mon will spread fresh winds into the northern waters of Baja California Norte Mon accompanied by increasing northerly swell that will raise wave heights across the Baja waters to 6-9 ft. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Fresh SW winds prevail across the southeast portions of the low pressure at 09.5N86W, where seas are 7-8 ft. Elsewhere moderate southwest winds prevail south of 09N east of 90W, with gentle winds north of 10N. Wave heights are generally 5-7 ft in mixed south to southwest swell. Large seas generated across the Tehuantepec region will continue to propagate into the offshore waters of Guatemala and El Salvador before gradually subsiding Mon. REMAINDER OF THE AREA... A trough extends along 135W, from 12N to 19N. Fresh to locally strong winds are noted within 120 nm NW of the trough axis, with seas of 8-10 ft. The trough will continue to shift W through the weekend. A 1024 mb low pressure center persists just N of the area near 32N135W. Associated swell generated by this system has subsided to 7-8 ft over NW portions of the discussion area. Fresh NW swell will begin to propagate into the far NW waters Sun night. Strong high pressure will build south-southeastward across the area through the weekend. This will strengthen NE tradewinds generally from 09N to 23N to the west of 125W Sun and Mon. Seas across this tradewind zone are expected to remain generally 7-10 ft in northwest swell through the weekend. $$ Stripling