000 AXPZ20 KNHC 101540 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sun Dec 10 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... Tehuantepec Storm Warning: A strong cold front is moving across the Gulf of Mexico today, resulting in the development of a gap winds in the Gulf of Tehuantepec that will reach gale-force today, then storm-force tonight. Peak seas should reach around 20 ft tonight and Mon morning. Storm-force winds will end Mon morning, but gale- force winds and rough seas will prevail in the region of Tehuantepec into Wed. Please read the latest High Seas Forecast and the Offshore Waters Forecast issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and www.nhc.noaa.gov/marine/offshores.php for details on the special feature. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 08N78W to 06N92W. The ITCZ extends from 06N92W to 08N122W to beyond 06N140W. Scattered moderate and isolated strong is convection noted from 06N to 10N W of 121W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please refer to the SPECIAL FEATURES section for details on a Storm Warning for the Tehuantepec region due to gap winds. High pressure over the U.S. Great Basin is forcing strong to near gale NW winds over the Gulf of California with seas 6-9 ft. This wind surge over the Gulf of California is also causing some fresh to strong NE gap wind just west of the Baja California peninsula. Strong gap winds are also developing in the Gulf of Tehuantepec. Elsewhere, surface ridging extends from a 1029 mb high off of California to near the Baja California and SW Mexico coasts. Only gentle to moderate winds are resulting over the open Pacific waters. Seas over Pacific waters are generally 5 to 7 ft. For the forecast outside of the Gulf of Tehuantepec, the high pressure over the U.S. Great Basin will continue forcing strong NW winds over the central and N Gulf of California through tonight. A recurrence of fresh to strong NW winds over the Gulf of California may begin Thu night. Large NW swell will gradually subside off Baja California later today. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The pressure gradient between higher pressure over the NW Caribbean and the monsoon trough to the south is forcing fresh to strong NE to E winds across the Papagayo region with seas 6-7 ft. Gentle to moderate breezes are occurring elsewhere with seas 3-6 ft. For the forecast, the pressure gradient between higher pressure over the W Caribbean and the monsoon trough to the south should continue forcing fresh to strong NE to E winds across the Papagayo region through the next several days. Gentle to moderate breezes are expected elsewhere. Otherwise, storm-force gap winds north of the area over the Gulf of Tehuantepec will generate large NW swell that will affect the Guatemala and El Salvador offshore waters tonight into Wed. ...REMAINDER OF THE AREA... The pressure gradient between the surface ridging along the W coast of Mexico and the ITCZ is forcing fresh to strong NE to E trades from 06N-21N west of 120W. Seas are 10-12 ft. Elsewhere, winds are gentle to moderate with 7-10 ft seas in large NW swell. For the forecast, the surface ridging should weaken by Tue, diminishing the trades. Seas should drop below 8 ft Wed over the tradewind belt. Tonight into Mon night, fresh to strong NE winds associated with Tehuantepec gap winds will reach into the high seas waters to 10N105W with seas 8-12 ft. A large, long- period swell should reach the NW corner of the waters Wed and gradually decay while moving SE through the end of the week. $$ Konarik