000 AXPZ20 KNHC 182104 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Fri Sep 18 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...TROPICAL WAVES... A tropical wave axis is along 119W from 05N to 16N, moving west at 10 to 15 kt. It shows up well in the lower half of the atmosphere, southwest of a upper level ridge. No significant convection is observed near the wave axis. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A segment of the monsoon trough extends from 12N86W to 17N102W . Another segment extends from 19N108W to 10N120W to 13N127W to a 1009 m low near 13N140W. Scattered moderate convection is noted from 11N to 17N between 100W and 105W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Weak deep layer ridging is observed between Baja California and about 125W, building east of the remnant low pressure over Karina which is slowing dissipating well west of the area. This ridge will build slightly through Sat as a trough north of the area moves into southern California. This pattern is supporting moderate to fresh winds off Baja California Norte along with combined seas to 7 ft. Winds and seas will diminish by Sun into early next week as the ridge weakens. The monsoon trough extends northward to off Zihuatanejo. Broad low pressure may be starting to form southwest of Cabo Corrientes between the segments of the monsoon trough. This may support fresh winds off the coast of Jalisco by Sun. Farther south, fresh to strong winds may pulse in the Gulf of Tehuantepec region by Sat night. Elsewhere, a weak pressure pattern across the region will result in mainly gentle to moderate winds and slight seas. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Gentle to moderate S to SW winds persist south of the monsoon trough. Elsewhere, gentle winds prevail north of the monsoon trough. Combined seas are currently in the 5 to 6 ft range in a mix of wind waves and southerly swell. REMAINDER OF THE AREA... The remnant low of Karina is located near 23N128W with a central pressure of 1012 mb, and will continue to move westward and gradually weaken to a surface trough later overnight. Moderate NE winds and seas of 5 to 7 ft in mainly NE swell persist between the low and subtropical ridge which is displaced well to the northwest. Because the remains displaced to the northwest, mostly gentle to moderate trade winds are noted farther south into the deep tropics. The ridge will gradually build eastward north of 20N through early next week, resulting trade winds increasing slightly between the ridge and the monsoon trough farther south. Farther east, seas are 7 to 8 ft in an area along the monsoon trough from 06N to 10N between 105W and 115W, a combination of moderate to fresh SW winds along with longer period SW swell. These seas will subside to below 8 ft through Sat, but reinforcing SW swell will arrive thereafter allowing seas to build to 8 ft again in this vicinity. $$ Christensen