000 AXPZ20 KNHC 181547 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sun Dec 18 2022 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. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from the coast of Panama near 08N79W to 07N93W to 07N106W. The ITCZ extends from 07N106W to 07N120W to beyond 07N140W. Scattered moderate isolated strong convection is noted from 04N to 08N and E of 84W. Scattered moderate convection is noted from 04N to 09N between 89W and 99W and from 06N to 10N between 125W and 139W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weak high pressure regime extends southward into the Baja California offshore waters. Light to gentle winds prevail across the Baja California offshore waters, Gulf of California, and southwest Mexico. Seas across these waters range 4-5 ft, with 3-4 ft in the Gulf of California. In the Gulf of Tehuantepec, strong northerly winds prevail with seas up to 9 ft. Light to gentle winds prevail elsewhere in the southern Mexico offshore waters with 4-5 ft seas. For the forecast, strong to near gale northerly winds will continue through Mon morning in the Gulf of Tehuantepec. Seas will continue to range 8-9 ft in this area through tonight. Conditions will rapidly improve on Mon afternoon. Strong NW winds are expected to develop in the Gulf of California Mon night and diminish on Wed night into Thu. Another gap wind event is expected in the Gulf of Tehuantepec from Tue afternoon through Thu. Gale-force winds are expected to develop Tue evening and continue through Wed afternoon. Seas may build to near 12 ft by Tue night into Wed morning. Conditions will improve on Thu afternoon across the Gulf of Tehuantepec briefly before the next gap wind event Thu night into Fri. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong easterly breezes are present in the Gulf of Papagayo region, extending westward to 90W. Seas are 6-7 ft in these waters. Light to gentle variable winds prevail elsewhere north of the monsoon trough. Gentle to moderate S-SW winds and seas of 4-6 ft are found south of the monsoon trough. Gentle or weaker winds and slight to moderate seas are noted across the South American offshore waters. Strong thunderstorms are also noted near and south of the Gulf of Panama from 04N to 08N between 77W and 84W. For the forecast, moderate to fresh easterly winds will continue in the Papagayo region through the upcoming week, pulsing to strong at night. Seas are expected to build near 8 ft at the time of the strong winds. Moderate to locally fresh northerly winds likely tonight and Mon night in the Gulf of Panama. Gentle winds will continue to prevail across the South American offshore waters through most of the week with moderate seas. REMAINDER OF THE AREA... A weak 1015 mb low pressure is centered near 29N125W and a surface trough extends southwestward to 30N139W. A few shallow showers are noted near the trough axis. Moderate winds are likely occurring near the low. The remainder of the area is dominated by high pressure system located well north of the eastern tropical Pacific. A frontal system is west of 140W, but likely bringing fresh to locally strong winds and seas near 8 ft in waters N of 27N and W of 138W. Elsewhere, light to variable winds are occurring N of 20N and W of 115W with seas 5-7 ft. Moderate to locally fresh winds are noted from the ITCZ to 20N and W of 110W, with gentle to moderate southerly winds south of the ITCZ. Seas range 7-9 ft. Elsewhere, moderate or weaker winds with slight to moderate seas are prevalent. For the forecast, moderate to locally fresh trade winds and 8-9 ft swell S of 20N and W of 125W are expected through midweek before it merges with large swell that will propagate into the waters by Wed. The frontal system currently located W of the forecast waters will continue to bring fresh to locally strong southerly winds N of 28N and W of 130W through Mon with seas building to 8 ft. Looking ahead, high pressure will shift east while strengthening through early next week. This will yield a broad zone of fresh tradewinds S of 20N and W of 120W starting Tue and continuing through most of the week. Another frontal system will approach the NW waters on Tue night into Wed, bringing strong winds and potential gale force winds N of 20N and W of 130W. Large swell with seas building to near 20 ft will also propagate through this area Tue night through most of the week. $$ AReinhart