000 AXPZ20 KNHC 121551 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sat Oct 12 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 1200 UTC surface analysis and satellite imagery through 1545 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Moderate NE to N winds across the southwestern Gulf of Mexico are funneling through the Isthmus of Tehuantepec and accelerating over and downstream of the waters of the Gulf of Tehuantepec. This scenario is producing the first fall season gale-force gap wind event in the Gulf of Tehuantepec gap region. High pressure extending southward along the Sierra Madre Orientals of Mexico will persist through early Mon, and maintain a tight pressure gradient across the Tehuantepec region. This is expected to sustain the ongoing gale-force gap winds through late Sat night. Overnight satellite scatterometer winds showed northerly winds to around 35 kt over Tehuantepec with gale-force winds extending to 90 nm offshore. This wind is producing seas to 12 ft. Peak seas will build to 13 ft by this afternoon. The pressure gradient should relax on Sun allowing for winds to diminish to fresh to near gale-force over the region through early Mon, 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 that is NW Colombia to 11N86W to 09N98W to low pressure near 08N107W 1010 mb and to 08.5N114W, then transitions to ITCZ and continues to 08N130W to beyond 08N140W. Scattered moderate convection is within 180 nm south of the trough between 88W and 92W, and within 120 nm south of the trough between 103W and 108W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Weak high pressure ridging extends from a 1020 mb high that is centered well W of the the Baja California waters near 27N132W southeastward to near the Revillagigedo Islands. This pattern is producing gentle to moderate northwest winds across the waters north of Punta Eugenia, where seas are 5-7 ft in NW swell. Light to gentle NW to N winds and seas of 4-6 ft prevail elsewhere over the Baja California offshore waters to the Revillagigedo Islands. Variable winds less than 12 kt prevail across Gulf of California, where seas are 3 ft or less. Over the rest of the Mexican offshore waters, outside of the Gulf of Tehuantepec, light to gentle winds and moderate seas prevail, except for moderate winds near Cabo Corrientes. For the forecast, a broad ridge will support moderate northwest winds across the Baja waters north of Cabo San Lazaro, and slight to moderate seas through Mon night. Expect fresh winds near Sebastian Vizcaino Bay Sat evening through early Sun. New northwest swell is expected to begin to reach the area waters early on Sun. This will build seas over the Baja California Norte waters to a peak of about 9 ft through Mon, then diminish slightly through Tue morning. A more significant NW swell is expected to move into the region Tue afternoon through the middle part of next week. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A gale-force gap wind event in the Gulf of Tehuantepec is producing seas of 6-8 ft in N-NW swell across the far western waters offshore of Guatemala. Fresh NE to E gap winds are spilling across the Papagayo region, and extend about 120 nm offshore. Seas have built to 6-7 ft there. Elsewhere N of 10N, light to gentle winds prevail. South of 10N, gentle SW to W winds extend from 90W to the Gulf of Panama and the coast of Colombia, where seas of 3-5 ft prevail. Seas up to 6 ft in SW swell are across the waters NW through E of the Galapagos Islands. Scattered moderate isolated strong showers and thunderstorms are occurring over the nearshore waters of western Panama and Costa Rica, and are well offshore of the coasts elsewhere from the Papagayo region to Guatemala. For the forecast, moderate northeast winds are expected over the far western part of the Guatemala offshore waters through the weekend due to the ongoing Tehuantepec strong gap wind event. Seas with these winds will build to around 9 ft in NW swell merging with new SW swell. Moderate gap winds will pulse nightly to fresh in the Papagayo region through Mon. New cross- equatorial south to southwest swell is expected during the weekend, raising wave heights a few feet across the regional waters. 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... High pressure of 1020 is located near 27N132W. A ridge extends south-southwestward from this high into the tropics. Meanwhile a weakening stationary front crosses 31N140W as it stretches northeastward and southeastward from there. The associated pressure gradient is producing moderate to locally fresh NE trade winds south of 22N to the ITCZ and west of 122W, while light to gentle winds prevail elsewhere east of 120W to the Mexican offshore waters. Seas of 5-7 ft in mixed S and NW swell prevail over waters north of the ITCZ, except for new NW swell moving into the far NW waters where seas are 7-9 ft to the N of 28N. Moderate southerly winds are south of the monsoon trough. Seas with these winds are generally 7-10 ft in fresh southerly swell For the forecast, the weak high pressure will move little through the weekend, then drift westward and strengthen slightly into the middle of next week. The associated anticyclonic wind flow will continue 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 across the waters south of 15N will gradually decay through Mon. New NW swell propagating southeastward across the far northwestern waters tonight will produce seas of about 8-9 ft today, decaying thereafter. A more significant NW swell is expected to reach 30N140W and the northwest waters late Sun night through Tue. Seas may reach a peak of about 11 ft with this next NW swell event. $$ Aguirre