000 AXPZ20 KNHC 150907 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Oct 15 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 0600 UTC surface analysis and satellite imagery through 0830 UTC. ...TROPICAL WAVES... The axis of a tropical wave is along 93W, south of 20N moving westward at 5 kt. Scattered moderate isolated strong convection is from 08N to 12.5N between 92W and 96W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N76W to 10N99W to low pres 1011 mb near 09.5N118W to 08.5N126W, then transitions to the ITCZ and continues to beyond 08N140W. Scattered to numerous strong convection is noted N of 02.5N E of 81W. Scattered moderate isolated strong convection is noted from 08N to 14.5N between 91W and 109W, and from 07N to 11N between 110W and 140W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... High pressure is centered over the NW Gulf of Mexico and extends southwestward to eastern Mexico. The pressure gradient between this area of high pressure and lower pressure within the EPAC monsoon trough continues to support fresh to strong northerly winds across the Gulf of Tehuantepec, that extend offshore to near 14N. Seas over these waters are in the 7-9 ft range. Elsewhere, weak high pressure ridging extends from a 1024 mb high pressure centered W of the the Baja California waters near 30N134W southeastward to just west of the Revillagigedo Islands. The pressure gradient between this ridge and a trough over the Gulf of California is supporting moderate to locally fresh NW to N winds over the Baja California waters north of Cabo San Lazaro, where seas are in the 6-8 ft range in NW swell. Gentle to locally moderate SW to W winds have developed tonight across most of the Gulf of California, with westerly gap winds to near 15 kt across the prominent gap regions. Seas are 3 ft or less. Over the rest of the Mexican offshore waters, light to gentle winds and moderate seas prevail. For the forecast, strong gap winds across the Tehuantepec region will gradually diminish to fresh speeds by late Tue morning, then weaken quickly, before returning to fresh to strong speeds again Thu into the coming weekend. Otherwise, moderate to NW winds across the Baja California Norte waters will spread southward to the Baja California Sur waters today and continue through early Thu, pulsing to fresh near the coast during the evening hours. Winds are expected to weaken modestly on Thu. A cold front is expected to move southward through Baja Norte Fri afternoon and night and reach central portions on Sat before dissipating. Low pressure will develop across the northern Gulf of California Thu through Fri to induce moderate to fresh SW to W gap winds across the Gulf basin, becoming strong across north portions Fri. A significant NW swell is expected to move into the regional waters later this morning and spread southeastward through Thu, with seas offshore of Baja California Norte building to 8-11 ft Tue evening and night. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The strong gap wind event in the Gulf of Tehuantepec continues to generate northerly swell moving into the far western waters offshore of Guatemala, producing seas 6-7 ft. Moderate to fresh NE gap winds are across the Gulf of Papagayo region and extend westward to 89W. Seas with these winds are in the 5-7 ft range. Elsewhere north of the monsoon trough, along about 10N, light to gentle winds prevail. South of the monsoon trough, gentle to moderate southwest to west winds prevail, where seas of 4-6 ft in SW swell prevail. Scattered to numerous strong convection is shifting westward off the the coast of Colombia into the waters E of 81W and across eastern Panama. For the forecast, moderate gap winds will continue across the Papagayo region today, and pulse to fresh Tue night before becoming light and variable for the next few days. Seas across the area waters will slowly subside across the region through Fri as gentle to moderate winds persist, and small NW and SW swell dominates the area waters. New cross-equatorial S swell will enter the regional waters Fri night through Sat. ...REMAINDER OF THE AREA... High pressure of 1023 mb is analyzed near 30N133W. The pressure gradient between this area of high pressure and lower pressure in the vicinity of the ITCZ is supporting moderate to locally fresh trade winds south of 24N to the ITCZ, and west of 123W. Seas over this area are 6-8 ft in mixed swell. Light to gentle winds are in the vicinity of the high center, where seas are in the 8-13 ft range in fresh NW swell, as confirmed by recent satellite altimeter data. The pressure gradient between the area of high pressure and a trough over the Gulf of California is supporting gentle to moderate northerly winds east of the high center, and west of 115W, where seas are in the 6-7 ft range. Light to gentle winds, and moderate seas are elsewhere N of the monsoon trough. Gentle to moderate winds, and seas of 5-7 ft prevail S of the ITCZ/monsoon trough. For the forecast, the aforementioned high pressure will drift slowly westward through Wed and then west of 140W early Thu. The associated anticyclonic wind flow will continue to dominate the waters north of the ITCZ today, producing moderate to fresh trade winds south of 20N and west of 130W through Thu night. Mainly gentle to moderate winds will prevail across the open waters through Thu. Cross-equatorial swell over the waters south of 15N will gradually decay through Tue, with new southerly swell crossing the equator Fri through Sat. New NW swell spreading across the far NW waters will move through the regional waters through Wed night. Seas will peak near 13 ft along 30N this morning with this NW swell. A cold front will sink into the northern waters Thu night and reach near 20N by Sat before dissipating. This will bring moderate NE swell into the regional waters. $$ Stripling