000 AXPZ20 KNHC 171527 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Wed Nov 17 2021 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 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 FEATURES... Gulf of Tehuantepec Gale Warning: A cold front is forecast to move through the Gulf of Mexico Thu into Fri with high pressure building behind it across eastern Mexico. The building high combined with lower pressure south of southern Mexico will support a gale-force northerly gap wind event from early Fri through Sat morning. Seas will build to around 12 ft during the event. Please see the latest NWS High Seas Forecast issued by the National Hurricane Center at website://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more information. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 11N86W to 08N102W to 11N117W to 1010 mb low pressure near 10N118W to 1011 mb low pressure near 08N127W. The ITCZ extends from 07N129W to 09N134W. Scattered moderate and isolated strong convection is noted from 05N to 09N between 77W and 86W, from 10N to 14N between 90W and 93W, and from 05N to 09N between 97W and 113W. Scattered moderate convection is noted from 09N to 11N between 120W and 122W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details on a Gulf of Tehuantepec Gale Warning. Fresh to strong N-NE winds are across the Gulf of Tehuantepec with seas to 8 ft. A surface ridge extends across the offshore waters with mainly gentle to moderate winds across the waters outside of the Tehuantepec region. Seas are in the 4 to 6 ft range across the open waters. Seas are 2 to 4 ft in the southern Gulf of California, and 3 ft or less in the central and northern Gulf of California. For the forecast, fresh to strong northerly winds in the Gulf of Tehuantepec will gradually diminish to moderate to fresh by this afternoon. A gale force northerly gap wind event is forecast in the Gulf of Tehuantepec early Fri through Sat morning. Fairly tranquil conditions are forecast elsewhere through the upcoming weekend. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR Moderate to fresh winds prevail across the Papagayo region. Otherwise, light to gentle winds are noted north of the monsoon trough. Gentle to moderate southerly winds prevail south of the monsoon trough. Seas are in the 4 to 7 ft range across the majority of the offshore waters, highest south of Panama and west of Colombia and Ecuador. Scattered showers and thunderstorms are noted south of Panama and Costa Rica, and west of Colombia. For the forecast, moderate to fresh winds will prevail in the Papagayo region through Fri. Fresh to strong winds will return Fri night into Sat, then moderate to fresh thereafter. Gentle to moderate winds will prevail across the rest of the area through the next several days. REMAINDER OF THE AREA... A broad and weak ridge extends from north of the area to near 20N110W. A pair of weak surface lows are embedded in the monsoon trough, with a 1010 mb low near 10N118W and a 1011 mb low near 08N127W. Associated convection with these lows has diminished somewhat overnight into the early morning. A surface trough is west of the lows extending from 16N135W to 07N137W. Scattered showers are near the northern portion of the trough. Moderate to locally fresh trades are noted north of the convergence zone to 22N, with gentle to moderate winds north of there under the ridge. Gentle to moderate southerly flow prevails south of the monsoon trough. Seas of 5 to 7 ft prevail south of 22N, with 4 to 5 ft north of 22N. For the forecast, little change is expected through the end of the week. A cold front may drop south into the far northern waters Fri night. High pressure may build behind the front with freshening winds for the end of the weekend into early next week. $$ Lewitsky