000 AXPZ20 KNHC 180345 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sun Feb 18 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 0300 UTC. ...SPECIAL FEATURES... Significant NW Swell Event and Gale Warning: A deep low pressure center northwest of the area near 37N144W is accompanied by storm force winds. Large swell generated from this system is starting to enter the discussion area. Winds to gale force are ongoing near 30N140W, on the southeast quadrant of the low pressure. The associated swell is reinforcing a previous group of large, long period with 8 to 14 ft combined seas covering much of the discussion area north of 15N and west of 125W. The new group of swell will bring 12 to 22 ft combined seas to the discussion area north of 20N and west of 130W through late today, with higher seas north of area. These seas will subside through late Tue, but not before seas to 12 ft reach the coast of Baja California Norte. Gulf of Tehuantepec Gale Warning: A surface ridge building east of the Sierra Madre mountains in Mexico will introduce the next gap wind event in the Tehuantepec region later this morning. Winds are forecast to peak at gale to strong- gale force from this morning through Mon morning. Seas under these winds will range from 10 to 15 ft. Afterward, strong to near- gale force gap winds are expected to persist through midweek next week, possibly pulsing to gale-force Mon night through 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... The surface trough extends from 07N78W to 04N85W to 08N105W to 03N120W. The ITCZ continues from 03N120W to 01N130W to 02N140W. Scattered moderate convection is evident from 03N to 06n between 90W to 97W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features section above for information about the upcoming Tehuantepec Gale Warning. A tight pressure gradient between a 1020 mb high pressure off Baja California and lower pressure over southern Mexico is sustaining fresh to strong NW to N winds, and 6 to 9 seas off western Oaxaca. This same high is also supporting moderate to fresh northerly winds and seas of 2 to 5 ft across the offshore waters of Baja California, central Mexico and the Gulf of California. Mostly gentle winds and seas at 4 to 6 ft in moderate southerly swell prevail for the rest of the southern Mexico offshore waters. For the forecast, strong NW to N winds and rough seas will shift to near western Oaxaca State this evening before subsiding late tonight. Gale-force gap winds will begin in the Gulf of Tehuantepec by Sun morning through Mon afternoon. Large, long- period NW swell is forecast to reach the Baja California offshore waters by Sun morning, and near the Revillagigedo Islands on Sun night. It will cause very rough seas in these waters through midweek next week. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR Fresh to strong NE to E gap winds and seas at 5 to 7 ft persist across the Gulf of Papagayo and the coast of Nicaragua. Light to gentle winds with 2 to 4 ft seas are noted at the offshore waters of Costa Rica, western Panama and Colombia. Moderate N winds and seas of 4 to 5 ft are found in the Gulf of Panama. Gentle to moderate southerly winds and 4 to 6 ft seas in moderate S swell prevail at the waters near Ecuador and the Galapagos Islands. Refer to the Monsoon Trough/ITCZ section for convection in the area. Relatively benign marine conditions will prevail for the next several days. A gap wind event along with rough seas are anticipated in the Papagayo region from Mon to beyond midweek next week, as a ridge builds over the northwestern Caribbean. Fresh to strong NE to E gap winds could reach gale-force Wed night into early Thu morning. Looking ahead, fresh N winds and building seas are expected over the Gulf of Panama by late Mon. ...REMAINDER OF THE AREA... Please read the Special Features section above for information about the ongoing Significant Swell event, and an upcoming Gale Warning. A cold front is analyzed from 30N126W to 25N135W, moving into a 1020 high pressure near 26N123W. A second, reinforcing cold front is pass to the southeast of 30N140W. Strong SW winds are noted within 300 nm east of the second front, reaching gale force overnight along 30N. See the Special Features section for more details. Elsewhere large, long- period NW swell in excess of 8 ft extends over the waters north of 05N and west of 120W. Combined seas are 5 to 7 ft elsewhere. Moderate winds are evident in most areas, except as noted near the reinforcing front. For the forecast, the high pressure will gradually drift southward and weaken through the weekend, which should allow winds north of the ITCZ/trough to subside Mon and Tue. The aforementioned cold front is forecast will continue moving E tonight while weakening. A second stronger cold front will enter the northwest corner of the discussion area this evening, then merge with the first cold front on Sun. High pressure building southeastward behind the merged front will cause winds and seas north of the ITCZ to increase again by midweek next week. $$ Christensen