000 AXPZ20 KNHC 121526 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1306 UTC Tue Nov 12 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURE... Gulf of Tehuantepec Gale Warning: A cold front will reach the SW Gulf of Mexico later today. Unseasonably strong high pressure will build in the wake of the cold front, and induce gale force gap winds in the Gulf of Tehuantepec this afternoon. Winds will funnel through the Chivela Pass, and are expected to peak near 45 kt in the Gulf of Tehuantepec tonight, with seas building to near 20 ft during this time. The pressure gradient will relax on Wed as the area of high pressure shifts eastward, with winds diminishing below gale force on Wed night. Another gale force gap wind event is possible across the region Fri and Sat. See the latest High Seas Forecast under AWIPS/WMO headers HSFEP2/FZPN03 KNHC or the website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. ...TROPICAL WAVES... The axis of a tropical wave is near 101W from 03N to 13N, moving W at around 15 kt. Isolated to scattered moderate convection is noted where the wave meets the monsoon trough. The axis of a tropical wave is near 125W from 03N to 15N, moving W at around 10 kt. Scattered moderate isolated strong convection is observed from 07N to 10N between 124W and 130W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N83W to 08N100W to 14N118W to a 1009 mb low pressure near 13N125W to 09N131W to 10N136W to 09N140W. Scattered moderate isolated strong convection is from 04N to 07N E of 81W and the coast of Colombia, and within about 120 nm south of the monsoon trough between 82W and 110W. Similar convection is also seen from 08N to 12N between 110W and 114W and from 06N to 10N W of 133W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... The next Gulf of Tehuantepec gale force gap wind event is expected to begin this afternoon. Please see the Special Feature section above for more details. Elsewhere, a ridge dominates the offshore forecast waters west of Baja California, supporting gentle to moderate northerly winds, and seas generally 4 to 6 ft. Little change is expected through Thu. Strong high pressure building across north and central Mexico is supporting fresh to locally strong NW to N winds and 7 to 8 ft seas near the entrance of the Gulf of California and farther south between Cabo Corrientes and Los Cabos. Winds and seas are expected to diminish by tonight as the high pressure shifts eastward. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate SW monsoonal flow will continue across the offshore waters of Costa Rica, Panama, Colombia, and Ecuador the next several days. Seas will remain in the 4-7 ft range. Large seas generated by a strong gale force gap wind event in the Gulf of Tehuantepec will reach the offshore waters of Guatemala and El Salvador tonight into Wed, with seas building to 10 to 14 ft in northerly swell. REMAINDER OF THE AREA... A cold front currently near 30N140W will extend from 30N138W to 26N140W tonight. Seas of 8 to 9 ft in NW swell are expected W of the front. Large long period NW swell associated with an intense low pressure system in central northern Pacific will reach the NW waters on Thu. Seas associated to this swell event will peak near 13 or 14 ft over the far NW waters by Thu night. Looking ahead, an area of low pressure is expected to form in a couple of days several hundred miles south of the southern tip of the Baja California peninsula. Some gradual development of this disturbance is possible late this week before upper-level winds increase over the weekend. This system is expected to move slowly northward or northwestward during the next several days. The latest Tropical Weather Outlook gives this system a low chance of tropical cyclone formation through 5 days. $$ GR