752 AXPZ20 KNHC 080912 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sun Dec 8 2019 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: High pressure built southward across eastern Mexico and into the Tehuantepec region during the past 24 hours. The enhanced N to S pressure gradient is supporting minimal gale force N to NE gap winds over the Gulf of Tehuantepec, which will continue until just before sunrise on Sun. Peak seas currently to 13 ft will subside Sun as the pressure gradient weakens and winds diminish to fresh to strong speeds. Looking ahead, another gale force gap wind event is expected to affect the Gulf of Tehuantepec Wed evening as a stronger cold front crosses the Gulf of Mexico. Winds across Tehuantepec may reach 45 kt this with next event. See latest NWS High Seas Forecast issued by National Hurricane Center under AWIPS/WMO headers HSFEP2/FZPN03 KNHC or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N74W to 07.5N85W to 06.5N100W. The ITCZ continues from 07N100W to 06N109W to 07.5N125W to beyond 05.5N140W. Scattered moderate isolated strong convection is present from 04N to 10N between 80W and 104W, and within 150 nm N and 120 nm S of the ITCZ between 123W and 132W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gentle winds prevail across most of the offshore waters, as weak high pressure resides over the waters W of Baja to around 121W. Recent scatterometer winds showed variable mainly N to NW winds at less than 10 kt across most of the offshore waters N of 20N. Seas are building in NW swell to 5-8 ft and are expected to reach 6-9 ft this afternoon before subsiding very slowly through Tue. Inside the Gulf of California, recent scatterometer data showed NW winds 10-15 kt south of the Tiburon Basin, with seas 2-5 ft. Winds and seas are expected to diminish modestly through Mon afternoon or evening before high pressure begins to build into the region, and freshen winds across both the Gulf of California and the offshore waters of Baja. Elsewhere across the Mexican offshore waters, variable and gentle winds prevail from Cabo Corrientes to Puerto Angel. Strong to gale force northerly gap winds prevail over the Gulf of Tehuantepec, but will diminish below gale force by sunrise, and then continue to gradually diminish to less than 20 kt by Mon morning. Please see the Special Features section above for more details on the Gulf of Tehuantepec Gale Warning. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The latest GOES-16 satellite imagery shows scattered moderate isolated strong convection along the monsoon trough from 04N to 10N between 80W and 104W. A weak low level perturbation along 96W will continue to move westward and maintain active convection along and ahead of it. NE to E winds less than 15 kt generally prevail across the offshore waters N of 10N and W of the papagayo region. Strong NE to E winds will near 20 kt will pulse to around 25 kt each night across and downstream of the Gulf of Papagayo through Tue, with seas peaking between 8 and 9 ft downstream of the Gulf each morning. Elsewhere, gentle to moderate S to SW monsoon flow will persist across the offshore waters of Costa Rica, Panama, Colombia, and Ecuador during the next several days. REMAINDER OF THE AREA... The remnants of an old cold front have merged with a lingering trough farther south and extend from 30N121W to 14N130W. High pressure prevail to the NW of this weak boundary where NE to E winds of 15 kt or less prevail N of 20N and 15-20 kt S of 20N to the ITCZ and W of 110W. Large NW swell continues to propagate SE across the region, with seas of 9-13 ft dominate the waters NW of the trough. This NW swell will continue propagating SE through Mon and gradually decay to around 8 ft to the S of 16N by Mon night. Looking ahead, another cold front will approach the NW portion of the discussion area Mon and introduce new NW swell into the NW waters through the middle of next week. $$ Stripling