000 AXPZ20 KNHC 072208 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2121 UTC Sat Dec 7 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 1800 UTC surface analysis and satellite imagery through 2130 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A cold front extending across the W Gulf of Mexico to near Tampico Mexico will continue moving SE today. High pressure is currently building S over eastern Mexico into the Tehuantepec region. The enhanced N to S pressure gradient is supporting minimal gale force N to NE gap winds over the Gulf of Tehuantepec, which will continue through Sun. Seas will peak between 12 and 13 ft downstream of the Gulf tonight, then subside Sun as the pressure gradient weakens and wind speeds diminish to fresh to strong speeds. Looking ahead, another gale force gap wind event could affect the Gulf of Tehuantepec Wed into Thu as a stronger cold front crosses the Gulf of Mexico. See latest NWS High Seas Forecast issued by National Hurricane Center under AWIPS/WMO headers HSFEP2/FZPN03 KNHC or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 08N78W to 09N84W to 06N94W to 07N100W. The ITCZ continues from 07N100W to 07N125W to 05N140W. Scattered moderate convection is present within 180 nm either side of the monsoon trough. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Fresh to locally strong NW winds continue over the central and southern Gulf of California between a low pressure trough passing over the Mouth of the Gulf of California and Sonora Mexico and a weak high pressure ridge over the Baja California offshore waters.These winds will persist today, then diminish to moderate speeds on Sun. Peak seas are currently peaking around 6 ft across southern portions of the Gulf and will gradually subside through Mon. Elsewhere, gentle winds prevail across most of the offshore waters, as weak high pressure resides over the waters W of Baja to around 125W. A weakening cold front is pushing slowly SE across the far NW waters approaching 125W. Elsewhere across the Mexican offshore waters, variable and gentle winds prevail, except for increasing northerly gap winds over the Gulf of Tehuantepec. Please see the Special Features section above for more details on the Gulf of Tehuantepec Gale Warning. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The latest GOES-16 satellite imagery shows scattered moderate to strong convection continues along the monsoon trough from S of the Gulf of Tehuantepec to off the coast of Colombia. Strong NE to E winds will pulse to around 25 kt each night across and downstream of the Gulf of Papagayo through Tue, with seas peaking between 8 and 9 ft downstream of the Gulf each morning. Elsewhere, gentle to moderate S to SW monsoon flow will persist across the offshore waters of Costa Rica, Panama, Colombia, and Ecuador during the next several days. REMAINDER OF THE AREA... A weakening cold front extends from 30N123W to 25N130W to 24N140W. Scattered moderate convection is evident in satellite imagery behind the front in the vicinity of a trough extending from 30N133W to 27N140W. Large NW swell associated with the weakening front is spreading across the region, as seas greater than 12 ft dominate the waters NW of the front. Recent altimeter data suggests seas as high as 13 ft near 30N135W. This front will continue slowly moving eastward across the northern waters tonight, then weaken and dissipate as it crosses 120W tonight. Large NW swell will continue propagating SE through the weekend. Seas will remain greater than 12 ft over the northern waters today, then subside tonight and Sun. Looking ahead, another cold front will approach the NW portion of the discussion area Mon and introduce new NW swell into the NW waters through the middle of next week. $$ Formosa