000 AXPZ20 KNHC 190333 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Mon Oct 19 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 0230 UTC. ...TROPICAL WAVES... A tropical wave axis extends along 116W from 05N to 17N, moving W at 10 to 15 kt. Associated convection is described below. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from near 10.5N77W to 09N84W to 12N94W to 10.5N113W to 12N137W to beyond 10.5N140W. Scattered moderate to strong convection is noted from 04.5N to 10.5N between80W and 91W, from 08N to 16.5N between 99W and 122W, and from 08N to 12.5N between 122W and 130W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of Tehuantepec: Strong high pressure dominating the Gulf of Mexico for the past few days continues to shift slowly NE with associated ridging weakening across the SW Gulf. This has significantly weakened the forcing of northerly gap winds through the Isthmus of Tehuantepec and across the Gulf of Tehuantepec during the past 24 hours. Winds across Tehuantepec are expected to remain northerly for the next few days and return to the nocturnal pulses of 25-30 kt each late night and early morning, and extend only 90-120 nm downwind in a relatively narrow plume. Presently strong northerly winds extend only about 60 nm offshore with seas 6-7 ft, but will strengthen overnight, with this pattern expected to persist through Thu. A 1020 mb high pressure is centered west of Baja California near 29N126W. The pressure gradient between the high pressure and lower pressure over the Sonoran desert is supporting moderate to fresh NW winds across the offshore waters of northern and central Baja California from Punta Eugenia northward. Farther south, with exception of a small area of strong winds across the Gulf of Tehuantepec, gentle to moderate breezes persist. Seas are generally in the 4 to 7 ft range in mixed N and SW swell. The winds across the offshore waters of Baja California will continue through early week, with locally strong winds Mon. Mostly gentle to moderate breezes and slight seas will persist elsewhere. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Moderate to fresh SW winds prevail south of the monsoon trough along about 09N-10N and east of 95W. Seas are 5 to 7 ft primarily in SW swell. Building high pressure north of the region will support pulses of moderate to fresh gap winds through the Gulf of Papagayo and southern Nicaragua this evening. Expect moderate to fresh SW winds and seas building 7 to 9 ft in SW swell south of Costa Rica and Panama Mon through Tue. REMAINDER OF THE AREA... A deep layer trough along 136W-137W S of 25N extends south to a surface low of 1011 mb near 17N138W. Scattered moderate convection is presently occurring north of the low and along and east of the trough from 17.5N to 22.5N between 131W and 139W. This low and associated trough will weaken as it moves NW tonight, then will move W of the region Mon. High pressure will then build north of 20N, supporting fresh trade winds early this week from roughly 15N to 25N mainly west of 125W. Farther east, seas will will remain near 8 ft tonight near the monsoon trough between 110W and 120W, due in part to fresh northerly swell emerging out of the Gulf of Tehuantepec and new longer period SW swell moving into the area. $$ Stripling