000 AXPZ20 KNHC 161601 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Fri Feb 16 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. Updated Offshore Waters and Remainder Of Area sections ...SPECIAL FEATURES... Significant NW Swell Event: A complex low pressure system over the northeast Pacific Ocean will bring two groups of large swell to the shipping lanes between southern California and Hawaii over the next several days. The first swell group i associated with a cold front currently moving across the NW corner of the forecast area. This system will bring combined seas of 12 to as high as 18 ft tonight into early Sat over the area north of 20N and west of 135W. This swell will subside slightly as it spreads to the southeast through Sat, with combined seas of 12 ft or greater covering the waters north of 12N and west of 125w by Sat night, just as the second swell group starts entering the area following another cold front to reinforce the first swell group. By late Sun night, long-period NW swell of 8 ft or greater will cover most the area west of 110W, with 12 to 22 ft combined seas mainly north of 15N and west of 125W. Combined seas will subside below 12 ft in the discussion area by Tue night, although rough seas will persist in most areas. Marine interests in the region need to monitor this developing situation and plan their route accordingly. Gale Warning near 30N140W: In addition to the large swell, winds ahead and behind the second front are expected to briefly reach minimal gale force by Sat evening, mainly N of 28N and W of 138W. Fresh to strong winds will persist on both side of the front through at least Sun night. Gulf of Tehuantepec Gale Warning: A new gap wind event is expected in the Tehuantepec region by early Sun morning. At that time, winds are forecast to suddenly increase to gale force with seas building to 9 to 12 ft. Gales are expected to persist through Mon. Please read the latest High Seas issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The equatorial trough extends from 05N77W to 01N84W to 1011 mb low pressure near 04N95W to another 1011 mb low pressure area near 03N113W to 02N122W. The ITCZ continues from 02N122W to beyond 02N140W. Scattered moderate convection is noted from 03N to 05N between 95W and 97W, and from 03N to 06N between 110W and 115W. Similar convective activity is near 10N106W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A Gale Warning has been issued for the Gulf of Tehuantepec. Please see the Special Features section for details. 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 strong NW to N winds off Jalisco and Colima this morning, including off Cabo Corrientes. Seas are estimated to be 6 to 8 ft in this area. Farther to the south, winds at Salina Cruz on the southern end of the Tehuantepec isthmus have been around 20 kt. This is supports fresh to strong northerly gap winds across the Gulf of Tehuantepec, possibly reaching near- gale at times. Farther north, fresh N winds may be funneling between the coast of Baja California Norte and the 1024 high pressure near 29N125W. Gentle to moderate winds and moderate seas are noted elsewhere. For the forecast, the strong winds and rough seas will persist off Cabo Corrientes and the coasts of Jalisco and Colima this morning, between high pressure off Baja California and lower pressure over southern Mexico. These winds and seas will shift southeastward toward Michoacan and Guerrero today through Sat, but diminish slightly. Farther south, fresh northerly winds will persist in the Tehuantepec region trough through this morning then diminish. Looking ahead, the next Gulf of Tehuantepec gap wind event will begin early Sun, reaching gale-force through Sun night into Mon. Large NW swell is forecast to reach the Baja California offshore waters Sat night into Sun causing very rough seas into midweek next week. By Mon morning, seas of 8 to 10 ft are forecast to dominate most of offshore waters of Baja California. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR Recent scatterometer and altimeter satellite passes confirm a large plume of fresh to strong NE to E winds persist across the Gulf of Papagayo and the coast of Nicaragua with combined seas of 6 to 8 ft. Gentle to moderate winds and moderate seas are noted elsewhere. For the forecast, the fresh to strong easterly gap winds and rough seas will persist in the Papagayo region and off Nicaragua into Sat, pulsing to near-gale force tonight. Elsewhere, relatively benign marine conditions will prevail for the next several days. The next gap wind event is anticipated in the Papagayo region by early next week. Looking ahead, winds expect fresh N winds over the Gulf of Panama by late Tue. ...REMAINDER OF THE AREA... Please read the Special Features section at the beginning about an upcoming Significant Swell event. A broad mid to upper level trough reaches from off Baja California Norte southward to 10N110W. Divergence aloft associated with the trough is supporting clusters of showers and thunderstorms along an associated surface trough from 09N110W to a 1009 mb low pressure area near 04N115W. Recent scatterometer satellite pass confirmed a large area of 20 to 30 kt winds within 300 nm west of this trough. Nearby altimeter satellite pass indicated seas of 8 to 12 ft in this area. This is embedded in a larger area of fresh trade winds and rough seas in mixed swell covering the waters within 300 nm north of the equatorial trough and ITCZ west of 105W. Farther north, SW winds are increasing to near-gale force north of 28N and west of 130W ahead of an approaching cold 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. For the forecast, the aforementioned high pressure near 29N125W will remain quasi-stationary through today, then drift slowly southward tonight through the weekend ahead of a cold front moving across the NW part of the forecast area. The front is forecast to reach 30N135W to 26N140W this afternoon, and from 30N128W to 23N140W by Sat afternoon. Fresh to strong winds with very rough seas are expected ahead and behind this boundary through Sat morning. Another cold front will reach the NW corner of the forecast region by Sat evening accompanied by fresh to strong winds and reinforcing swell. $$ GR