000 AXPZ20 KNHC 010305 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sat Feb 1 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 0200 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Northerly gap winds have just begin to spill across the nearshore waters of the Gulf of Tehuantepec during the past couple of hours, as a strong cold front is moving across the southern Gulf of Mexico. High pressure building behind the front will provide a very tight pressure gradient over the Tehuantepec region during the next 24-36 hours, and bring about a rapid increase in winds funneling across the Gulf of Tehuantepec. Winds will rapidly increase to gale force around sunrise Sat, and reach near storm force Sat night into Sun. Seas are expected to peak near 22 ft by Sun morning. Winds of 20 to 30 kt and seas of 8 ft or greater will extend downstream of the Tehuantepec region to beyond 100W by Sun morning. Winds will diminish rapidly late Sun night and Mon as the high shifts eastward and weakens. Please read the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 or at website https://www.nhc.noaa,gov/text/MIAHSFEP2.shtml for further details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough axis extends from 09.5N74.5W TO 04.5N78W TO 04N94W. The ITCZ continues from 04N94W TO 08N109W, then resumes from 06N122W TO beyond 04.5N140W. Scattered moderate isolated strong convection is noted within 90 nm either side of a surface trough from 16N105W TO 09N121W. Scattered moderate convection is noted within 120 NM N of the ITCZ between 124W AND 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Northwest swell will continue to dominate the forecast waters west of Baja California through Sat, with seas in the 7 to 10 ft range. Seas are forecast to subside to 5 to 7 ft by Sat night. A ridge dominates the offshore forecast waters W of Baja California producing mainly gentle to moderate NW to N winds W of Baja California, and fresh northerly winds across the Gulf of California. Fresh to locally strong winds are expected across the Gulf of California tonight through midday Sat as high pressure across the Great Plains builds southward into northern Mexico. Seas are expected to peak around 7 ft through central portions of the Gulf during this time. A deep layered upper trough well offshore of Mexico is pulling abundant middle and upper level moisture from the tropics between 110W and 120W, northeastward across central Mexico this evening. Multi-layered clouds and a few embedded showers and thunderstorms will stream northeastward across western Mexico tonight, between Acapulco and central portions of Sinaloa, as well as Baja California Norte. A cold front will sweep southeastward across the northern half of the Baja California Peninsula Sun and Mon, to significantly increase the winds and seas west of Baja California Norte. A 1042 mb high pressure will follow the front, bringing a very tight pressure gradient just off the coast of southern California. Fresh to strong NW winds and seas in the 12 to 18 ft range are expected just off Baja California Norte Sun night into Mon. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A weak pressure pattern will prevail through Sat, with tranquil winds across offshore waters, except for moderate to fresh gap winds over the Papagayo and Gulf of Panama regions. A tightening pressure gradient over Central America will induce strong winds in the Gulf of Papagayo region and fresh northerly winds across the Gulf of Panama during the late night and early morning hours Sat night through Mon night. Large NW swell will affect the waters off Guatemala and El Salvador on Sun and Mon, generated from gale force winds in the Gulf of Tehuantepec. REMAINDER OF THE AREA... A ridge extends from a 1030 mb high near 32N133W to near the Revillagigedo Islands. The pressure gradient south of the ridge is supporting fresh to strong NE trades from 06N to 23N W of 125W, with seas of 9 to 12 ft in mixed NE and NW swell. The ridge will weaken tonight through Sun, and the trades will diminish. A dying cold front will reach the far northwest part of the area near 30N140W Sat, then stall and dissipate through Mon. A surface trough is analyzed on the 0000 UTC surface map and extends from 16N105W TO 09N121W. Fresh to strong northerly winds and seas to 9 ft are noted within about 120 nm W of the trough axis. The trough has drifted NW in the past several hours but is forecast to move eastward extending from 14N110W to 07N114W by Sat morning, with fresh to strong winds and seas 8 to 10 ft within about 210 nm W of the trough axis. Winds will diminish to 20 kt or less in association with this trough by Sun morning, but seas to 8 ft will persist on the E side of the trough roughly from 13N to 16N between 110W and 113W. On Sun morning, also expect fresh to strong northerly winds and seas to 8 ft near Cabo Corrientes. Long period NW swell dominates the rest of the forecast waters, with seas 8 ft or greater covering much of the area north of 05N and west of 115W. Swell will gradually diminish the next few days, with the areal coverage of 8 ft or greater seas shrinking this weekend. Significant long period NW swell will sweep into the waters north of 20N Mon and Tue. $$ Stripling