000 AXPZ20 KNHC 280941 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sun Nov 28 2021 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 140W. The following information is based on satellite imagery, weather observations, radar, and meteorological analysis. Based on 0600 UTC surface analysis and satellite imagery through 0915 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: The pressure gradient between high pressure over eastern Mexico and lower pressure south of the Gulf of Tehuantepec within and near the monsoon trough will induce north to northeast gale-force winds across the Gulf of Tehuantepec starting tonight. These conditions winds will continue through Mon night. Seas will peak to near 11 ft with the strongest winds. Please see the latest NWS High Seas Forecast issued by the National Hurricane Center at website://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more information. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northwestern Colombia to 09N84W to 08N96W to 09N110W to 10N123W, where over overnight scatterometer data indicates that it transitions to the ITCZ to 09N130W and to beyond the area at 10N140W. Scattered moderate convection is within 30 nm of the monsoon trough between 111W- 114W and within also between 133W-137W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO Please see the Special Features section above for details on the next gale-force northerly gap wind event expected in the Gulf of Tehuantepec beginning tonight. Elsewhere, light and variable winds prevail over the Gulf of California. An area of fresh northwest to north winds are over the waters between Cabo Corrientes and Mazatlan. Seas are 4-5 ft offshore of the Baja California Peninsula mainly due to a northwest swell, and 4-6 ft elsewhere west of the Gulf of Tehuantepec area. For the forecast, gale-force north to northeast winds will begin in the Gulf of Tehuantepec tonight and continue through late Mon night. Moderate to fresh northwest to north winds will develop near Cabo Corrientes tonight through late Mon night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR Moderate to fresh northeast winds prevail over and downstream the Gulf of Papagayo. Light to gentle winds are elsewhere north of the monsoon trough. Gentle to moderate winds continue south of the monsoon trough. Seas across the area are in the 3-5 ft range due to a south to southwest swell across the offshore waters. For the forecast, fresh to strong northeast winds in the Papagayo region will continue through the period. Gentle to moderate winds will prevail elsewhere through the next few days. REMAINDER OF THE AREA... High pressure prevails over the northern waters. The pressure gradient between this high pressure and lower pressures in the vicinity of the ITCZ is supporting moderate to fresh northeast to east trades north of the ITCZ to near 22N and west of about 116W. Seas are 6-8 ft across this area. Water vapor imagery depicts a mid to upper-level trough that extends from northern Baja California to 20N119W and to near 10N121W. A weak mid-level low is noted near 20N118W. At the surface, a trough extends from 18N114W to 12N115W. Upper divergence present east of these features is helping to sustain an area of scattered showers and thunderstorms from 16N to 20N between 109W-116W. Gentle to moderate northeast to east trades are elsewhere over the discussion waters as noted in latest ASCAT data passes. Seas of mainly 4-6 ft are elsewhere. For the forecast, the pressure gradient will weaken some through late this afternoon as a front approaches the far northwest corner of the area. This will allow for the aforementioned fresh winds to diminish in coverage. The 6-8 ft seas will subside slightly to 5-7 ft. Mainly gentle to moderate east trades will continue elsewhere through early next week, except for pockets of fresh trades west of about 130W. After today, the seas of 5-7 ft will continue through early next week over the majority of the area, with the exception of the far western waters north of 15N and west of about 135W, where a set of northwest swell will bring seas of 8-9 ft to those waters. $$ Aguirre