000 AXPZ20 KNHC 032121 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2120 UTC Tue Dec 3 2019 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. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N76W to 1011 mb low pressure near 08N95W to 1012 mb low pressure near 08N108W to 1011 mb low pressure near 11N126W to 1010 mb low pressure near 09.5N129W to 09N140W. Scattered moderate isolated strong convection is noted from 07N to 13N between 121W and 130W. Scattered moderate convection is occurring from 06N to 10N between 91W and 100W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Scatterometer data from around 1530 UTC indicates that earlier gale force winds over the Gulf of Tehuantepec have diminished to fresh to strong speeds. Elsewhere, moderate to locally fresh NW winds continue over the Gulf of California. Weak high pressure just south of Guadalupe Island is supporting gentle winds over the Baja California offshore waters. Seas remain 8-9 ft offshore of Baja in NW swell, while 8-10 ft seas extend well downstream of the Gulf of Tehuantepec in mixed NE and SW swell. The NW swell across the Baja California waters will begin decaying tonight, with seas subsiding below 8 ft on Wed. A pre-frontal trough just west of the Baja offshore waters will dissipate late tonight, and a weak cold front will pass over the northern waters Wed and Wed night. Fresh NW to N flow will resume over the central and southern Gulf of California Thu night through Fri night. A gale force Tehuantepec gap wind event is possible Fri night through Sat night as a cold front crosses the Gulf of Mexico. The next set of large NW swell will move across the waters off Baja California Sat through Sun. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong NE to E winds will pulse across and downstream from the Gulf of Papagayo through Sun. Moderate to locally fresh northerly winds will pulse across the Gulf of Panama through Thu, then diminish on Fri. Elsewhere, gentle to moderate S to SW monsoon flow will persist across the offshore waters of Costa Rica, Panama, Colombia, and Ecuador during the next several days, along with weak S to SW swell. REMAINDER OF THE AREA... Wave heights remain 8-12 ft in NW swell over much of the region roughly north of a line from 13N115W to 03N140W. A 15 UTC altimeter pass showed seas peaking around 12-13 ft near 10N140W. This swell will continue propagating SE while gradually decaying through Wed night. A low pressure trough extends from 30N124W to 25N126W, ahead of a cold front that is analyzed from 30N125W to 26N127W to 23N131W. Recent scatterometer data shows a large area of fresh to strong E to SE winds between the trough and surface high pressure over the Baja offshore waters. Another trough is analyzed farther south near 22N124W to 14N128W, with scattered moderate convection noted within 180 nm east of the trough axis. Elsewhere, smaller areas of fresh to strong winds and locally higher seas are associated with low pressure systems near 08N95W and 11N126W embedded along the monsoon trough. The cold front over the northern waters will move eastward and weaken tonight through Wed night. Another large set of NW swell will move into the NW waters Thu night and propagate SE through the weekend, building seas greater than 12 ft over the NW portion Fri through Sat. $$ Reinhart