000 AXPZ20 KNHC 010915 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Northerly gap winds spilling across the Gulf of Tehuantepec as a strong cold front is moving across the SW Gulf of Mexico. High pressure building behind the front will provide a very tight gradient over the Tehuantepec region during the next 24-36 hours. Winds will rapidly increase to gale force around sunrise this morning, and reach near storm force tonight 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 06N77W to 05N93W. The ITCZ continues from 05N93W to 07N106W to beyond 04.5N140W. Scattered moderate isolated strong convection is noted north of the ITCZ within an area bounded by 18N103W to 08N117W to 17N118W to 26N114W to 18N103W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Northwest swell will affect the waters west of Baja California today, with seas in the 7 to 8 ft range. Seas are forecast to subside to 5-7 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 today 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 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 stream northeastward across western Mexico today between Acapulco and central portions of Sinaloa, as well as Baja California Sur. 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 W of Baja California Norte. Strong 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 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 in the Gulf of Papagayo region and fresh northerly winds across the Gulf of Panama during the late night and early morning hours 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 ridge extends from a high near 33N131W to 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 through Sun, and the trades will diminish. A dying cold front will reach the far northwest part of the area near 30N140W later today, then stall and dissipate through Mon. Strong to near gale force sustained northerly winds with gusts greater than 35 kt were indicated from 08N to 11N between 114W and 118W on a scatterometer pass at 0400 UTC. Satellite imagery showed a well-defined gust front moving southward from active convection. Seas are estimated to be 10-12 ft. Winds associated with the feature will diminish to 20 kt or less by Sun morning, but seas to 8 ft will persist, 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 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. $$ Mundell