000 AXPZ20 KNHC 160407 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Thu Nov 16 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 0000 UTC surface analysis and satellite imagery through 0330 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning...High pressure persisting across Mexico and the western Gulf of Mexico, behind a slow moving cold front across the central Gulf of Mexico, will continue to support gale-force gap winds funneling into the Gulf of Tehunatepec through early Thu. Peak seas downwind of Tehuantepec are expected to fluctuate between 10 and 14 ft tonight, then begin to diminish Thu morning to below 12 ft. NW seas generated across Tehuantepec will spread into the outer offshore waters of Guatemala, where seas will remain 7 to 10 ft through late tonight. Strong gap winds, and associated seas, will gradually diminish Thu into the weekend. Large area of high seas...Large NW to N swell, generated by complex low pressure and an associated frontal system across the NE Pacific, continue to propagate southeastward into the open NW waters of the discussion area tonight. Seas of 12 ft and greater have spread SE to a line from 30N123W to 24.5N127W to 17.5N140W this evening, with peak seas to 20 ft along 30N133W. This area of 12 ft seas has nearly reached its farthest SE extent, and will begin to gradually subside late tonight through Thu evening, when seas will fall below 12 ft. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 11N74.5W to low pressure near 11.5N81.5W 1007 mb to 07N99W to low pressure near 10N109W 1007 mb to 09N115W to low pressure near 16N121W 1007 mb to beyond 08.5N140W. Scattered moderate isolated strong convection is noted from 05N to 13N E of 88W. Scattered to locally numerous moderate to strong convection is noted from 06N to 16N between 116W and 128W, and from 17.5N to 25N between 116W and 121W. Scattered moderate convection is from 07N to 11N W of 128W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See Special Features Section above for details on a Gale Warning in association with gap winds in the Gulf of Tehuantepec. Weak high pressure just offshore of central Baja California supports light to gentle variable winds across the water north of 20N, except the entrance to the Gulf of California, where moderate N to NW winds prevail. Seas of 6 to 8 ft in NW swell prevail across the Baja offshore waters. Seas are 1 to 3 ft inside the Gulf of California, except 4 to 5 ft across the entrance. Elsewhere across the southwest Mexico waters, winds are light to gentle and seas are 5-7 ft in mixed swell. For the forecast, NW swell propagating across the Baja California Norte offshore waters will reach the Baja Sur waters by Thu evening then gradually subside across the area through Sun. The pressure gradient between high pressure over the Great Basin and low pressure along western Mexico will support moderate to fresh NW winds across central and southern portions of the Gulf of California tonight through Sun, then expand into north portions and increase to fresh to strong Sun evening through Mon night. High pressure will build across the Baja offshore waters Sat afternoon through Sun to bring a return to moderate to fresh northerly winds. Fresh to strong N winds will pulse again in Tehuantepec Fri evening through Sun. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Light to gentle winds prevail N of 08N, along with seas of 5-7 ft, except well offshore Guatemala where seas are 8 to 10 ft in NW swell due to ongoing Gulf of Tehuantepec gale-force gap winds. Elsewhere, moderate SW to W winds are ongoing south of the monsoon trough, except over the Galapagos Islands, where S winds are gentle, with 6 to 8 ft seas in S-SW swell across the area. For the forecast, moderate winds will pulse briefly to fresh tonight in the Gulf of Papagayo. Light to gentle winds will prevail elsewhere N of 09N through the forecast period. Meanwhile, southerly swell will continue across the area waters through the weekend producing seas of 5 to 8 ft. Seas are expected to remain 7 to 10 ft in NW swell across the outer offshore waters of Guatemala into Thu afternoon due to the extended period of Gulf of Tehuantepec gale-force gap winds. Winds and seas are expected to diminish modestly area-wide Sat through early next week as broad low pressure across the SW Caribbean lifts NE and away from the region. ...REMAINDER OF THE AREA... A cold front continues to move slowly across the NW waters extending from 30N122W to 18N140W. A narrow band of moderate to fresh S to SW winds is found ahead of the front to the N of 26N reaching to 117,W with seas in the 8 to 10 ft range in NW to N swell. Fresh to strong NW to W winds follow the front W of 128W, with seas in the 12 to 20 ft range. Moderate W to SW winds are elsewhere between the front and 128W, with seas 10 to 14 ft. Elsewhere, a surface trough extends from 24N120W to just north of low pressure of 1007 mb near 16N121W. Moderate to fresh winds are on either side of the trough, with seas of 7 to 9 ft mainly W of the trough axis. Scattered convection, described above, is occurring E of the trough axis, supported by a broad and energetic deep layered upper trough covering most of the NE Pacific N of 20N, A weakening high pressure ridge dominates the remainder of the waters between N of 20N and E of 120W, and is supporting moderate or less winds with seas to 7 ft. South of 10N, moderate SE winds prevail with southerly swell supporting 6 to 8 ft seas in SE swell. For the forecast, the front will continue to move E-SE through tonight, then stall and weaken in the vicinity of 122W Thu. Very large seas in excess of 12 ft will gradually spread SE and reach as far E as 125W by tonight before seas gradually subside through Thu night. Elsewhere, seas of 8-9 ft across the W-central waters will slowly subside, ahead of the large NW swell dominating the NW waters. Looking ahead, trade winds will start to increase this weekend as high pressure builds back across the region. $$ Stripling