000 AXPZ20 KNHC 012218 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Gale force northerly gap winds continue to spill across the Gulf of Tehuantepec this afternoon as a strong cold front has moved across the south-central Gulf of Mexico and across most of the Yucatan Peninsula. High pressure building behind the front will produce a very tight pressure gradient over the Tehuantepec region during the next 36 hours, supporting gale force winds across and downstream of Tehuantepec. Winds across the area are expected to reach near storm force tonight into Sun, with seas expected to peak around 20 ft by Sun morning. Winds of 20 to 30 kt and seas of 8-12 ft 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 10N75.5W TO 04N78W TO 07.5N87W TO 07N94W. ITCZ extends from 07N94W TO 07.5N109W, then resumes from 05N116W to beyond 05.5N140W. Scattered moderate convection is noted from 10N TO 16.5N between 105W AND 118W. Scattered moderate isolated strong convection noted within 120 NM N AND 60 NM S OF ITCZ between 129W AND 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A broad surface ridge dominates the offshore forecast waters W of Baja California producing mainly gentle to moderate NW to N winds W of Baja California, and moderate to fresh northerly winds across the Gulf of California. Winds are expected to diminish modestly this evening through tonight through Sun as high pressure weakens across the area ahead of an approaching cold front. Winds will shift to southerly across the Gulf of California and along the Pacific coast of Baja California, and increase significantly Sun afternoon through evening. The cold front is expected to move from the Pacific waters into Baja California Norte Sun night through Mon morning. SW winds ahead of the front will increase to 30 kt in the northern Gulf of California, while NW winds reach 20-30 kt across the far northern waters behind the cold front. The front is expected to reach central portions of Baja California Mon night and move into southern portions by Tue night. Expect large NW swell producing seas to 18 ft across the offshore waters behind the front on Mon. A deep layer upper trough well offshore of southern Mexico is pulling abundant mid-level moisture from the tropics between 110W and 120W northeastward across central Mexico. Multi- layered clouds, embedded showers and a few thunderstorms will continue to stream northeastward across western Mexico today between Acapulco and central portions of Sinaloa, as well as Baja California Sur. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A weak pressure pattern persists today 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 across the Gulf of Papagayo region and fresh northerly winds across the Gulf of Panama tonight 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 surface ridge extends from a weakening 1031 mb high near 34N129W to just NW of the Revillagigedo Islands. The pressure gradient south of the ridge is supporting fresh NE trades from 06N to 21N W of 125W, with seas of 9 to 12 ft in mixed swell. The ridge will weaken through Sun, and the trades will diminish. A dying cold front will reach the far northwest part of the area near 30N140W this evening, then stall and dissipate through Mon. Strong northerly winds with gusts potentially around 35 kt are suggested by satellite imagery this afternoon to the NW of a surface trough located from 12N110W to 07N115W, where are estimated to be 9-11 ft. Winds associated with the feature will diminish to 20 kt or less by mid morning Sun. 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 couple days, with the areal coverage of 8 ft or greater seas shrinking. Significant long period NW swell will sweep into the waters north of 20N Mon and Tue. $$ Stripling