000 AXPZ20 KNHC 011603 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Thu Dec 1 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 1500 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: High pressure building across the eastern slopes of the Sierra Madre mountains in Mexico currently supports a gale-force gap wind event across the Tehuantepec region. Seas will build to 11-12 ft by tonight. The gale force winds will persist trough early Fri morning. Then, strong to just below gale force winds are then expected to continue through Fri night, extending offshore to about 12N, before winds increase again to gale force Sat through Sun night as the high pressure strengthens again across the western Gulf of Mexico. Winds are then expected to gradually diminish Mon and Mon night. Please see the latest High Seas Forecast at http://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. Of note, the 20-year climatology of the Tehuantepec gap wind events indicates that on average 16 gale-force events and 5 storm-events occur in the Gulf of Tehuantepec per cold season. Most gale-force events occurred during November and December, while most storm-force winds occurred in January. Pacific Gale Warning: A strong cold front across the open NE Pacific is sinking southward and will reach the NW corner of the forecast area this afternoon. Strong to minimal gale-force winds and large seas follow the front forecast to reach from 30N131W to 27N140W this evening. Seas will build to 15-18 ft behind the front in mixed NE wind sea and strong NW swell. Gale conditions are expected to end by late tonight as the front moves slowly southward and the pressure gradient relaxes. Please see the latest High Seas Forecast at http://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gentle to moderate NW winds prevail across the offshore waters of Baja California to Cabo Corrientes early this morning. Seas are generally 4 to 6 ft in NW swell. Light winds and seas 3 ft or less prevail inside the Gulf of California. Elsewhere across the remaining Mexican offshore waters, mainly light to gentle winds and seas of 4 to 5 ft are noted. Strong NW to N winds continue to gradually expand in areal coverage across the western half of the Gulf of Tehuantepec, where peak winds are 30 kt and seas to 8 ft. For the forecast, gale-force winds are blowing across the Tehuantepec region. Please, see the Special Features section for more details. Gale force winds are expected to return to the Tehuantepec area Sat through Sun night as the high pressure strengthens again across the western Gulf of Mexico. Winds are then expected to gradually diminish Mon and Mon night. A cold front is expected to reach the Baja California Norte waters Sat, then stall and weaken quickly. Accompanying large NW swell will reach the Baja Norte waters Fri evening, with seas building to 8-10 ft N of Punta Eugenia Fri night, before beginning to slowly fade late Sat. High pressure will build across the Baja region Sun night through Mon and freshen the winds across the Baja waters. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh NE winds across the Papagayo region have increased to strong in recent hours, and extend downwind to near 91W. Peak seas are estimated at 8 ft. Light to gentle variable winds prevail elsewhere N of the monsoon trough along 07N, with seas of 4 to 5 ft while moderate S to SW winds and 5 to 6 ft seas are seen to the S of the trough. Gentle to moderate S to SW winds prevail off the Ecuador offshore waters to the Galapagos Islands with seas 4 to 5 ft. For the forecast, fresh gap winds over the Papagayo region will persist into the upcoming weekend, pulsing to strong each night through Sat night. These winds will extend beyond 90W tonight through Fri, then retract to E of 90W Sat afternoon through Sun. Elsewhere, little change in the marine conditions is expected. Mainly gentle to moderate winds will prevail across the offshore waters of Central America, Colombia, and Ecuador. Seas will subside modestly during the upcoming weekend except in the Papagayo region. NW swell generated from a significant Tehuantepec gap wind event will move across the offshore waters of Guatemala and El Salvador early Fri through Mon. REMAINDER OF THE AREA... A 1018 mb high pressure is centered across the northern forecast waters near 28N120W, and extends a ridge south and southeastward that covers roughly the waters N of 15N between 110W and 140W. Gentle to moderate NE to E winds and seas of 6 to 7 ft are dominating the area N of the monsoon trough/ITCZ to 20N and W of 120W. Moderate to locally fresh SE to S winds winds and seas of 6 to 8 ft are noted S of the monsoon to the equator and W of 120W. A low pressure is forecast to persist along the monsoon trough between 114W and 118W over the next 48 hours and help to focus active weather there. The low will move westward between 120W and 125W by Sat. An area of 6-8 ft seas will move in tandem with the low center. A cold front is approaching the far NW waters this morning. A pre frontal trough has entered those waters, and extends from 30N135W to 25N140W. Fresh to locally strong S to SW winds are occurring E of the trough N of 28N and W of 130W. Seas have built 7 to 8 ft there in fresh NW swell. Scattered moderate convection is within 120 nm SE of the trough. The cold front will sink southward into these far NW waters this morning, with NE gale force winds and large Nw swell behind it. See the Special Features section above for more details. For the forecast, the pre-frontal trough will move slowly SE across the NW waters into Thu, preceded by fresh to locally strong SW winds shifting ahead of it. A strong cold front will follow the trough, and will reach the NW waters after sunrise, and slowly sink SSE across the area waters. Gale force NE winds are expected behind the front W of 135W through late afternoon before gradually diminishing to around 30 kt. Strong to near gale force NE winds and large seas of 12-18 ft are expected behind the front through early Fri morning. Teh front is expected to reach from near 30N128W to 26N140W Fri morning, then begin to stall and weaken quickly. Large N swell generated behind the front will outrun the front Fri, and cross 20N Sat morning. A reinforcing cold front will weaken along 30N Sun. High pressure behind that front will strengthen winds to fresh to locally strong across much of the area N of the ITCZ and W of 115W on Mon. $$ GR