000 AXPZ20 KNHC 112152 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Fri Oct 11 2024 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 2145 UTC. ...SPECIAL FEATURE... Gulf of Tehuantepec Gale Warning: The pressure gradient will tighten between high pressure surging southward along the Sierra Madre Oriental Mountains of Mexico and the E Pacific monsoon trough over the weekend. This will lead to northerly gale force winds in the Gulf of Tehuantepec gap region starting tonight and continuing through Sat night. Presently, fresh to near gale force northerly winds are supporting seas of 8 to 12 ft. These seas will build to 14 ft late tonight into Sat. The pressure gradient should relax on Sun allowing for winds to diminish to fresh to near gale force over the region through late Sun, and at fresh to strong speeds going into the middle part of the upcoming week. Please read the latest High Seas Forecast at website: www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more information. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from low pressure in NW Colombia, westward to northern Costa Rica, and continues to a 1010 mb low near 10N88W, to another 1010 mb low near 10N95W, then to 08N101W to 08N114W. The ITCZ extends from 08N114W to 09N125W to 08N135W and to beyond 09N140W. Numerous moderate to isolated strong convection is within 120 nm south of the trough between 90W and 95W and between 101W and 109W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Weak high pressure ridging extends southeastward from a 1021 mb high that is well west of the these waters near 27N132W to the Revillagigedo Islands. Gentle to moderate northwest winds are north of Punta Eugenia. Seas over these waters are 5-7 ft in northwest swell. Seas are 4-6 ft in northwest swell elsewhere over the Baja California offshore waters. Light to gentle northwest to north winds are elsewhere over the Baja California offshore waters. Latest ASCAT data passes indicated light to gentle southeast to south winds in the Gulf of California, except for gentle to moderate southeast to south winds just east and southeast of Isla Angel de la Guarda in the northern part of the Gulf. Seas are 3 ft or less in the Gulf of California. Higher seas of 3-4 ft in mixed southwest and northwest swell are at the entrance to the Gulf of California. Over the rest of the Mexican offshore waters, outside of the Gulf of Tehuantepec, light to gentle winds and moderate seas prevail. For the forecast, with the exception of that described above for the Gulf of Tehuantepec region, a broad ridge will support moderate northwest winds north of Cabo San Lazaro, and slight to moderate seas through Mon night, except for brief fresh to strong winds near Sebastian Vizcaino Bay Sat night. A set of new northwest swell is expected to reach the area waters Sun. This will build seas over the Baja California Norte waters to a peak of about 9 ft through Mon, with little change into the middle part of next week. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... An ongoing gap wind event in the Gulf of Tehuantepec is producing moderate to locally fresh northerly winds over the far western part of the offshore waters of Guatemala. Seas over these waters are 5-8 ft in northwest swell that is being generated by the gap wind event. Farther south, gentle to moderate southerly winds and seas of 4-6 ft are occurring south of the monsoon trough. Gentle southwest to west winds are in the Gulf of Panama. North of the monsoon trough, light to gentle winds and moderate seas prevail. Scattered showers and thunderstorms are occurring over the outer offshore waters of Guatemala and El Salvador as well as along the immediate coastline of Costa Rica and that of the northern and central sections of Panama. For the forecast, moderate to fresh north to northeast winds are expected over the far western part of the Guatemala offshore waters through the weekend due to the ongoing Tehuantepec gap wind event. Seas with these winds will build to around 9 ft in northwest swell generated by the Gulf of Tehuantepec gap wind event. Moderate to fresh east winds will pulse nightly in the Papagayo region through Mon. A new set of cross-equatorial south to southwest swell is expected during the weekend. Elsewhere, mainly gentle to moderate southwesterly winds will prevail across the offshore waters south of 09N through the next few days. ...REMAINDER OF THE AREA... The pressure gradient related to high pressure of 1021 mb centered near 27N132W is allowing for moderate to fresh trade winds and seas of 5-7 ft over waters north of the ITCZ to 26N and west of 120W. Moderate to fresh southerly winds are south of the monsoon trough. Seas with these winds are generally about 7-9 ft from south swell mixing with northwest swell. Recent altimeter satellite data passes revealed these wave height values. Elsewhere, light to gentle winds and moderate seas are prevalent. For the forecast, the weak high pressure will move little through the weekend, with its associated anticyclone continuing to dominate the waters north of the monsoon trough through early next week. Mainly gentle to moderate winds will prevail across the open waters through Mon. Cross-equatorial swell has raised seas to 9 ft as far north as 10N between 110W and 125W. This swell will gradually decay through Sun. A new set of northwest swell producing seas of about 8-9 ft, possibly to 10 ft, will propagate southeastward of 30N140W tonight through Sat, decaying thereafter. A more extensive set of northwest swell is expected to reach 30N140W and the northwest waters late Sun night through Mon. Seas may reach a peak of about 11 ft, or slightly high with this set of northwest swell. $$ Aguirre