000 AXPZ20 KNHC 121558 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Thu Oct 12 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 1530 UTC. ...TROPICAL WAVES... A tropical wave has an axis along 96W north of 03N to the southern Mexico coast, moving westward at 10 to 15 kt. Scattered moderate convection is noted from 03N to 12N between 92W and 103W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from the coast of Costa Rica/Nicaragua border near 11N86W to 15N105W to 11N124W to beyond 10N140W. Scattered moderate convection is noted from 08N to 14N between 88W and 118W and from 07N to 11N W of 135W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge stretches across the Baja California offshore waters. Between this and a trough just east of the Gulf of California, the pressure gradient is supporting moderate to fresh winds across the Baja California Norte offshore waters. Northwest swell is bringing seas 8-12 ft across this area, N of 25N. Gentle to moderate winds are noted south of Punta Eugenia with 5-7 ft seas within NW swell. Moderate to locally fresh winds are noted in parts of the Gulf of California with 2 to 4 ft seas. Across southern Mexico, moderate to fresh winds are noted along the coast of Oaxaca, just west of the Gulf of Tehuantepec. Seas are around 8 ft in this area. Gentle to moderate winds are noted elsewhere in this region. Seas range 5 to 7 ft within mixed swell. No significant convection is noted across any of the Mexico offshore waters at this time. For the forecast, a ridge will continue to build eastward across the offshore waters of Baja California the remainder of the week. A swell event bringing 8 to 12 ft seas will propagate across the offshore waters of Baja California through Fri. In the Gulf of California, moderate to fresh winds are expected through tonight, then light to gentle winds during the weekend. The first Gulf of Tehuantepec gap wind event of this fall season is expected to begin on Sun morning, with fresh to strong N to NE winds continuing through most of next week. There is a possibility for these winds to reach gale- force Sun night through Mon night. October marks the beginning of the Tehuantepec wind events. Looking ahead, an area of low pressure is expected to form several hundred miles to the south of the southwestern coast of Mexico during the early to middle part of next week. Thereafter, some gradual development is possible while the system moves generally north-northwestward. Currently, the latest Tropical Weather Outlook gives this system a low chance of tropical cyclone formation through 7 days. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to locally moderate winds are north of 07N, and gentle to moderate south winds south of 07N. Southerly swell in the Ecuador offshore waters is bringing 7 to 8 ft seas. Seas are generally 4 to 7 ft elsewhere across the region in mostly a southerly swell. Strong thunderstorms are noted off the coast of Colombia from 02N to 07N and E of 82W. For the forecast, light to gentle winds will continue north of of the monsoon trough with gentle to moderate winds south of it through the weekend. Long-period southerly swell will continue bring 8 ft seas to the offshore waters of Ecuador through tonight, with seas up to 7 ft through Sat night. The southerly well will also propagate across most of the offshore forecast waters with seas of 5 to 7 ft through Sat. ...REMAINDER OF THE AREA... A ridge dominates the forecast waters N of 15N and W of 120W. The associated pressure gradient is allowing for generally gentle to moderate northeast to east trade winds and seas of 5 to 6 ft across this area. NW swell is bringing seas 8 to 12 ft seas across the NW portion of the waters, N of 25N and E of 132W. Elsewhere north of the monsoon trough and ITCZ, light to gentle northeast to east winds are present with seas of 4 to 5 ft. Gentle to moderate south to southwest winds are south of the monsoon trough. Seas there are 5 to 7 ft due to southerly long- period swell. For the forecast, the NW swell bringing rough seas to the NW portion of the waters will subside by Fri night. Meanwhile, high pressure over the area will gradually shift eastward and weaken through Fri as a cold front enters the northwest part of the area while weakening. A rather extensive set of northwest swell will follow in behind this front bringing seas of 8 to 10 ft to the far northwest waters starting Fri. Another cold front is forecast to reach 30N140W on Mon, bringing another set of swell to the area early next week. $$ AReinhart