000 AXPZ20 KNHC 151557 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sat Jan 15 2022 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 1200 UTC surface analysis and satellite imagery through 1530 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Expect light and variable winds across the Gulf of Tehuantepec region today into tonight. By late tonight, winds will give way abruptly to gale-force gap winds that are expected to continue through Sun night. This will occur as another cold front moves across the western Gulf of Mexico with high pressure building over the Gulf of Mexico and eastern Mexico behind it. Seas are expected to reach a peak of about 14 ft with this upcoming event on Sunday evening. Please see the latest NWS High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from the coast of Panama near 07N78W southwestward to 04N84W to 05N96W. The ITCZ extends from 05N96W to 07N115W to beyond 08N140W. No significant convection is noted at this time. OFFSHORE WATERS WITHIN 250 NM OF MEXICO A Gale Warning is in effect for the Gulf of Tehuantepec from tonight through Sunday night. Please see the Special Features section above for details. High pressure northwest of the region is supporting a weak pressure gradient across the Baja California offshore waters. Deep layered upper level low pressure west of 120W continues to support surface troughing between 118W and 128W, which continues to deflect high pressure to the west of the area. Moderate northerly winds continue prevailing across the Baja offshore waters to 18N. Seas are 5-7 ft in W-NW swell. Fresh to locally strong NNW winds prevail over most of the Gulf of California. Seas of 3-4 ft are in the central portion and 4-5 ft in the southern portion. Showers continue to stream across Baja California and the northern Gulf of California. Light to gentle W to NW winds are elsewhere across the open waters off Mexico from Cabo Corrientes to Puerto Angel, where seas are 4-6 ft. A cluster of showers and thunderstorms persist across the offshores of Guerrero and Oaxaca from 13N to 17N between 95W and 102W. This convection will continue through today. Marine conditions continue to be tranquil across the Gulf of Tehuantepec region with light to gentle winds. Seas are to 3-4 ft in a west to northwest swell. An area of 6-7 ft seas due to mixed northeast and northwest swell is located well to the southwest- west of the offshore waters and extends to 108W. This area of mixed swell will decay late today. Isolated thunderstorms are noted across the Gulf. Gale-force winds will develop across the Gulf of Tehuantepec late tonight through Sunday night with seas peaking over 12 ft by Sunday evening. Strong winds will pulse again by Mon night. Fresh winds across the Gulf of California will become strong later this evening and continue through Sun morning. Peak seas will reach 5-7 ft late tonight through Sun morning. Fresh winds will prevail through Sun night. W-NW swell will continue to move through the waters offshore of Baja California through Mon. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR High pressure across the Gulf of Mexico is supporting fresh NE to E gap winds across the Gulf of Papagayo and the Gulf of Panama. Seas in both Gulfs are reaching 4-6 ft. Light to gentle winds are noted elsewhere north of 05N. Seas are 3-5 ft outside of the Gulf of Papagayo and Gulf of Panama, mainly due to S to SW swell. Fresh northeast to east gap winds will continue across the Gulf of Papagayo through this morning, then strengthen fresh to strong late early Mon morning through the middle part of next week. Seas in the Gulf of Papagayo region will increase 6-9 ft early Tue into the middle part of next week. The Gulf of Panama will continue to pulse to fresh through the week, with seas reaching 6-7 ft with peak winds. Gentle to moderate winds will continue north of the trough with light to gentle winds south of the trough extending across the Central American offshores. REMAINDER OF THE AREA Moderate west to northwest swell is propagating through the north and west parts of the area west of a line from Baja California to 03N140W, where seas are 7-9 ft. Seas elsewhere are 7-8 ft west of 115W. An elongated and deep-layer upper-level low pressure system is presently stationary between 120W-130W from 15N to 32N, where a broad inverted surface trough is noted 122W- 128W to the north of 17N. Satellite imagery shows thunderstorms near the trough from 16N-20N between 126W-130W. Tropical moisture continues to be advected northward on the eastern side of the deep-layer low, roughly between 118W- 124W and reaches as far north as 32N. The pressure gradient between the surface trough and high pressure located to the northwest continues to promote moderate to locally fresh NE winds to the west of the trough. The upper level low is forecast to lift northward this weekend, allowing for mainly gentle north to northeast winds to persist west of the surface trough. Gentle to moderate easterly winds prevail elsewhere north of the ITCZ to 17N, and west of about 110W, except for mainly northeast winds west of 128W. The W-NW swell will gradually decay by Sun. The trough is forecast to drift W through Sun, while weak low pressure develops near 31N128W. This will maintain a weak pressure gradient across the regional waters and fairly tranquil marine conditions. Looking ahead, a new trough is expected to develop north of the ITCZ along 128W by Tue, and meander northward through mid week. Increasing winds and seas will be seen near the trough and north of 20N during this time, as the pressure gradient increases. $$ AReinhart