000 AXPZ20 KNHC 042212 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Mon Dec 4 2023 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 1800 UTC surface analysis and satellite imagery through 2130 UTC. ...SPECIAL FEATURE... Gulf of Tehuantepec Gale Warning: Strong high pressure continues to build over central Mexico. This is supporting a surge of northerly gap winds reaching gale force across the Gulf of Tehuantepec. This pattern will persist through much of week, with gales pulsing mainly at night through Thu night. Seas may reach 10 to 12 ft downstream of the strongest winds during the overnight hours. Please read the latest High Seas Forecast issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends off the coast of Panama/Colombia border near 07N78W to 06N97W. The ITCZ extends from 06N97W to 07N107W and then from 07N113W to beyond 10N140W. Scattered moderate convection is noted from 04N to 09N between 89W and 105W and from 04N to 11N between 112W and 140W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the SPECIAL FEATURES section for more information on the Gale Warning in the Gulf of Tehuantepec. A broad ridge extends across the offshore waters of Baja California from 1026 mb high pressure near 31N129W to the Revillagigedo Islands. The pressure gradient between the ridge and a trough located along the eastern shore of the Gulf of California supports fresh to locally strong NW to N winds over the central and southern Gulf of California. Seas range 4 to 6 ft in this area. The pattern is also supporting mainly moderate NW to N winds off Baja California. NW swell has moved across the Baja California Norte waters bringing 8 to 10 ft seas N of 23N. South of 23N, seas are 6 to 8 ft in NW swell. Farther south, light breezes persist off southern Mexico, with 4 to 7 ft combined seas in mixed swell. Scattered thunderstorms are occurring across the Michoacan and Jalisco offshore waters. For the forecast, outside of the gap wind event in the Gulf of Tehuantepec, long- period NW swell will persist off Baja California and the Revillagigedo Islands through most of the week. Seas as high as 12 ft could move across the California Norte waters by Wed night. Reinforcing NW swell will arrive off Baja California Norte by Thu night into Fri, accompanying a cold front moving into the region. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong NE to E winds are prevailing across the Gulf of Papagayo. Seas are 5 to 6 ft in this area. Gentle to moderate winds are noted elsewhere, with 4 to 6 ft seas primarily in SW swell. Scattered thunderstorms are noted south of the monsoon trough off the coast of Colombia. For the forecast, high pressure building north of the region will support pulsing strong winds across the Gulf of Papagayo particularly at night. Seas will build well offshore of Guatemala by Wed due to swell generated by gale- force gap winds in the nearby Gulf of Tehuantepec. Gentle to moderate winds are forecast elsewhere. Moderate combined seas will persist through mid week in a mix of SW and NW swell. ...REMAINDER OF THE AREA... High pressure dominates the waters north of 18N. Fresh to strong trade winds are noted south of the ridge, mainly from 10N to 27N west of 110W. Seas in this region are 9 to 12 ft, in a mix of locally seas due to the trade wind flow, and longer-period NW swell. Combined seas of 7 to 10 ft cover much of the region elsewhere west of 110W, although with primarily S to SE swell south of 10N. Gentle to moderate winds and 5 to 7 ft seas are noted east of 110W. A trough extends across the waters from 16N109W to 08N111W with scattered moderate convection around it from 08N to 16N between 109W and 112W. For the forecast, the high pressure will dissipate by Tue into Wed as a cold front moves eastward across the waters north of 25N Tue through Thu. This will allow trade winds to diminish slightly west of 110W through mid week. Large, long- period NW swell accompanying the front will move across the waters north of 10N and west of 120W through mid week. This swell will bring seas as high as 16 ft N of 25N and W of 130W on Tue. In waters east of 110W, the combination of the NW swell with shorter- period NE swell emerging from gap wind events and fresh E trade winds will support rough seas from 07N to 12N between 95W and 110W from Thu into Fri. $$ AKR