000 AXPZ20 KNHC 210337 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sat Nov 21 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 Tehuantepec Gale Warning: The pressure gradient between a high pressure ridge over the southeast United States and the eastern Pacific monsoon trough continues to support gale force northerly winds across the Tehuantepec region. Fresh to strong N to NE winds extend well offshore from Tehuantepec to near 12N101W. Peak seas to 12 ft prevail downwind of the Gulf. This long-lived gale event is expected to last through Mon morning. The leading edge of seas 8 ft or greater currently extend SW from the Gulf to near 106W and are forecast to reach as far west as 110W by Sat morning. 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 near 86W N of 03N, moving west at 10 to 15 kt. Scattered moderate convection is E of the wave axis N of 04N and extends across Costa Rica and Nicaragua. The axis of a tropical wave is near 104W, from 03N to 18N, moving west at 10 to 15 kt. Scattered moderate isolated strong convection is noted W of the wave axis to 114W between 07N and 13N, and within 180 nm E of the wave axis from 07N to 15N. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N75W to 08N83W to 07N107W. The ITCZ continues from 07N107W to 11N123W to beyond 10N140W. Scattered moderate convection is noted N of 04N E of 85W. Scattered moderate isolated strong convection is noted from 07N to 14N between 101W and 114W. 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 ridge extends southward across the Baja California offshore waters, extending from a 1030 mb high near 42N132W. The pressure gradient between this area of high pressure and a surface trough along the Gulf of California is supporting gentle to moderate northerly winds across the waters off the coast of Baja California. Gentle to moderate winds prevail elsewhere. Wave heights are 6-7 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 portions of the Gulf of California, where seas are 3-5 ft. These conditions will prevail through Sat and then improve modestly through Sun. High pressure will build south-southeastward over the offshore waters and gradually shift westward through the weekend. This will produce generally moderate winds across the Baja offshore waters north of 20N through Sun. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Moderate southwest winds are south of 10N east of 100W, with gentle winds north of 10N. Wave heights are generally 5-7 ft. Large seas generated across the Tehuantepec region will propagate into the offshore waters of Guatemala and El Salvador before gradually subsiding through the weekend. REMAINDER OF THE AREA... The remnant low of Post-Tropical Cyclone Polo is centered near 16.5N125W. Winds remain in the 20 to 25 kt range in association to this low. Seas of 8 to 10 ft are found to the N of the low. This remnant low of Polo is expected to dissipate tonight as it continues shifting WSW. A 1015 mb low pressure center currently just N of the area near 33N137W has an attendant cold front that extends across the NW waters from 30N134W to beyond 26N140W. The low will weaken, and the front will weaken to a trough later tonight. This low pressure system and front has generated northwest swell across the northwest part of the area, with seas peaking near 10 ft. Strong high pressure will build south-southeastward across the area through the weekend. This will strengthen NE tradewinds west of 120W. Seas across this tradewind zone are expected to remain generally 7-10 ft in northwest swell through the weekend. $$ Stripling