000 AXPZ20 KNHC 290311 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 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 0000 UTC surface analysis and satellite imagery through 0300 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 08N78W to 08N85W to 09N83W to 05N110W. The ITCZ continues from 05N100W to 08N120W to 06N130W beyond 07N140W. Scattered moderate convection is noted from 06N to 08N between 121W to 127W and from 06N to 08N between 132N to 138W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Recent observations from Salina Cruz on the southern end of the Tehuantepec isthmus indicates fresh northerly gap winds, hinting of strong gap winds persist over the adjacent Gulf of Tehuantepec waters. These winds will diminish through Tue as high pressure north of the area weakens. Seas are peaking at 8 to 10 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 cold front extends from just west of Nogales, Arizona, across the N Gulf of California, to 27N120W. An earlier scatterometer pass confirmed strong SW winds ahead of the cold front in the northern Gulf of California. These winds are likely diminishing through the overnight hours. Expect strong NW winds over the Gulf of California from Tue night through Wed night as high pressure builds in the wake of the cold front as it sweeps southward across the area. Peak seas are likely to reach 5-7 ft in the N Gulf of California and 6-8 ft in the central and S Gulf of California. Very large NW swell continuing to move into the waters west of Baja California today, will peak near 15 ft Tue and early Wed, and then gradually diminish through Thu. An altimeter pass from 00 ITCZ indicated seas to 14 ft just west of Guadalupe Island. On Fri and Sat another large NW swell event of around 12 ft seas should again impact the waters west of Baja California. 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 Tue 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 Tue. 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 in the Papagayo region. REMAINDER OF THE AREA... Ridging extends from a 1028 mb high at 31N139W east- 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. On Thu through Sat the NE trades will relax back to moderate to fresh conditions. The next cold front should reach the N border Thu night, but winds associated with it should reach only strong breeze or weaker. Very large NW swell up to 15 ft are continuing across the 30N border east of 132W today and Tuesday before diminishing through Thu. An altimeter pass along the 140W border indicated seas of 10-12 ft from 15N to 30N. Another very large NW swell event peaking around 18 ft may reach the NW corner of our waters beginning on Fri. $$ Christensen