000 AXPZ20 KNHC 170512 TWDEP Tropical Weather Discussion...Updated NWS National Hurricane Center Miami FL 0405 UTC Sat Feb 17 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 0000 UTC surface analysis and satellite imagery through 0330 UTC. Updated Special Features and Offshore Waters sections ...SPECIAL FEATURES... Significant NW Swell Event and Gale Warning: Very large, long-period NW swell generated by a vast gale-force low pressure near 46N144W is causing 12 to 22 ft seas west of a line from 20N140W to 26N135W to 30N1331W. Expect these seas to propagate eastward and stall near a line from 13N135W to 23N128W to 30N122W by early Sun morning. Then a storm-force low pressure currently north of Hawaii near 36N156W is going to track eastward through Tue. Reinforcing NW swell produced by this second low will prolong 12 to 20 ft seas in the same general area through Mon, then create seas of 12 to 13 ft in the Offshore Waters of Baja California Norte Mon evening through Tue night. In addition, a cold front associated with the second low is expected to bring near-gale to gale-force westerly winds north of 28N between 134W and 140W Sat afternoon through evening. Afterward, westerly winds north of 28N between 130W and 140W will stay at strong to near-gale force through Sun night. Gulf of Tehuantepec Gale Warning: A ridge building east of the Sierra Madre mountains in Mexico will introduce the next gap wind event in the Tehuantepec region by early Sun morning. Winds are forecast to peak at gale to strong-gale force from mid Sun morning through Mon morning. Seas under these winds will range from 10 to 15 ft. Afterward, strong to near-gale gap winds are expected to persist through midweek next week, possibly pulsing to gale-force Mon and Tue nights. Marine interests in the regions above need to monitor these situations and plan their routes accordingly. Please read the latest High Seas and Offshore Waters Forecasts issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml https://www.nhc.noaa.gov/marine/offshores_eastpac.php for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... An equatorial trough extends from 06N77W through low pressure at 04N109W to 02N119W. An ITCZ continues from 02N119W to beyond 01N140W. Scattered moderate convection is noted up to 90 nm along either side of trough between 95W and 120W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features section about an upcoming Gale Warning. A relative tight pressure gradient between high pressure off Baja California and lower pressure over southern Mexico and farther south over the equatorial trough is supporting an area of fresh to strong NW to N winds off the State of Colima base on recent scatterometer data. These winds extend farther SW of the offshore forecast waters reaching 110W. Seas are 8 to 10 ft within these winds based on altimeter data. The above mentioned high pressure of 1023 mb, located near 27N124W, is producing moderate to locally fresh NW across the offshore forecast waters of Baja California N of Punta Eugenia, and gentle to moderate winds elsewhere. Seas are 5 to 7 ft N of Punta Eugenia, and 3 to 5 ft elsewhere, including the waters between Los Cabos and Las Maria Islands. For the forecast, the area of strong winds and rough seas off Colima will persist and move southeastward toward Michoacan and Guerrero tonight into Sat morning, reaching Oaxaca by Sat evening, and the Tehuantepec region by Sat night. The next gap wind event will begin in the Gulf of Tehuantepec by early Sun morning with winds reaching gale force through Mon. Large NW swell is forecast to reach the Baja California offshore waters Sat night into Sun, and near the Revillagigedo Islands by Mon. It will cause very rough seas into midweek next week. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR Fresh to strong NE to E winds persist across the Gulf of Papagayo and the coast of Nicaragua, and downwind to about 91W with combined seas of 6 to 8 ft. Light and variable winds are noted E of 90W with light to gentle southerly winds between Ecuador and the Galapagos Islands. Outside of the Papagayo region, seas are generally 3 to 5 ft, except 5 to 7 ft across the offshore waters of Guatemala and El Salvador due to the gap wind event in the Papagayo area. For the forecast, fresh to strong easterly gap winds and moderate to rough seas will persist in the Papagayo region and off Nicaragua into Sat. Elsewhere, relatively benign marine conditions will prevail for the next several days. The next gap wind event is anticipated in the Papagayo region by Mon, with fresh to strong NE to E winds persisting through Wed. Gale conditions are possible Wed night as a ridge builds over the northwestern Caribbean. Looking ahead, fresh N winds are expected over the Gulf of Panama by late Tue. ...REMAINDER OF THE AREA... Please read the Special Features section at the beginning about an ongoing Significant Swell event, and an upcoming Gale Warning. A broad mid to upper level trough extends across NW Mexico, crosses Baja California Sur and continues SW over the open Pacific waters to near 02N130W. Strong SW winds ahead of this trough are transporting abundant moisture over Mexico into Texas and the southern states of the United States. A 1023 mb high pressure is situated near 27N124W and dominates most of the waters N of 15N and W of 110W. A cold front extends from 30N134W to 25N140W. Fresh to strong winds are on either side of the front. Altimeter data confirmed NW swell has already started to enter the discussion area, reinforcing existing 8 to 9 ft swell north of 28N and west of 125W. Moderate to fresh trades are noted per scatterometer data N of the ITCZ to about 20N and W of 120W. Based on altimeter data, seas are 8 to 10 ft within these winds. For the forecast, the aforementioned high pressure will drift slowly southward tonight through the weekend ahead of a cold front moving across the NW part of the discussion area. The front is forecast to reach from 30N130W to 22N140W by Sat afternoon. A second cold front will reach the NW corner of the forecast region by Sat evening. These fronts are forecast to merge on Sun. Hazardous marine conditions will be associated with these fronts. Please, see the Special Features section for more details. $$ Chan