000 AXPZ20 KNHC 291557 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Tue Dec 29 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 1200 UTC surface analysis and satellite imagery through 1530 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from the coast of Panama near 08N78W to 08N86W to 05N99W. The ITCZ continues from 05N99W to 08N117W to 05N140W. Scattered moderate convection is noted along the monsoon trough from 04N to 09N between 81W and 95W. Scattered moderate convection is noted along the ITCZ from 05N to 10N between 119W to 139W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A scatterometer satellite pass from 0330 UTC indicated 20 to 30 kt northerly gap winds in the Gulf of Tehuantepec. These winds will diminish today as high pressure north of the area weakens. Seas are peaking at 8 to 11 ft. The next gap wind event should return by late Sat as a cold front moves through the Gulf of Mexico. This likely will be a gale- force event on late Sat and Sun. Farther north, a weakening cold front extends from south-central New Mexico to the north-central Gulf of California. Moderate to fresh winds will continue across the Gulf of California into this evening. By tonight, strong NW winds will develop over the Gulf of California and continue through Wed night/Thu morning as high pressure builds in the wake of the cold front. Peak seas are likely to reach 5-7 ft in the northern Gulf of California and 6-8 ft in the central and southern Gulf of California. An altimeter pass at indicated seas nearing 11 ft to the east of Guadalupe Island with seas to 14 ft west of Guadalupe Island. This very large swell is expected to gradually subside by tonight. The next round of large swell will arrive once again by Thu night into Fri and continue into the weekend west of Baja California Norte. Meanwhile, swell in excess of 8 ft will spread southward to the Revillagigedo Islands by early Wed and near Cabo Corrientes by early Thu. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Fresh to strong NE gap winds will pulse across the Gulf of Papagayo region through the early part of today as high pressure remains in place over the W Caribbean, then diminish as the high pressure weakens and shifts east. Peak seas are reaching 8 ft through this morning and are also expected to subside later today. Elsewhere, winds and seas will be quiescent through at least Sat night over the Central American and equatorial waters. Another round of fresh to strong gap winds is possible by late Sat/early Sun in the Papagayo region. REMAINDER OF THE AREA... Ridging extends from a 1029 mb high at 30N140W southeastward toward Baja California Sur. The pressure gradient between the ridge and the ITCZ to the south are producing NE to E fresh to strong trades with the strongest winds from 18N to 22N west of 130W. The trades will increase and become more extensive through Wed night as the ridge strengthens. Seas will peak at 10-12 ft due to NW swell and NE wind waves. Meanwhile NW swell in excess of 8 ft persists across the region north of 05N and west of 110W. The ridge will weaken Thu and shift east ahead of an approaching cold front, allowing the NE trades to diminish back to moderate to fresh conditions. Maximum wave heights will subside to less than 12 ft, but the extent of the NW swell of 8 ft or greater will persist through Fri. While the front will stall near 30N140W by Thu night into early Fri, reinforcing NW swell will accompany the front, with wave heights 12 ft or greater covering the waters northwest of a line from Baja California Norte to 13N140W by Sat night/early Sun. $$ AReinhart