000 AXPZ20 KNHC 160925 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Thu Feb 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 0600 UTC surface analysis and satellite imagery through 0950 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: High pressure building across the eastern slopes of the Sierra Madre Mountains in Mexico will support the next gap wind event in the Tehuantepec region. Sustained gap winds reaching gale force are expected to start Fri morning and briefly increase to minimal storm force by Fri evening. Storm-force winds will diminish back to gale force early on Sat. Afterward, gale force winds will persist across the area through Sun morning. Seas are forecast to peak to 24 ft with this gap wind event Fri night into Sat. Large seas generated from this strong gap wind event will spread well away from the Tehuantepec area, including the Guatemala and El Salvador offshore waters. Marine interest transiting across or in the vicinity of the Gulf of Tehuantepec Fri night into Sat should be aware of this upcoming gap wind event, and take the necessary action to avoid these hazardous marine conditions. Please read the latest High Seas Forecast at https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more information on this event. Eastern Pacific Swell Event: Large and long period swell from the NW continues to propagate across the NE forecast waters. Winds have diminished to 15 kt or less across the area, but seas of 8 to 12 ft are still affecting the waters N of 24N between the Baja California coastal waters to 124W. This swell event is spreading southward across the offshore waters of Baja California, and will reach the Revillagigedo Islands on Thu. By tonight, seas are forecast to gradually drop below 12 ft, but a large area of 8 to 11 ft seas will continue to affect the waters N of 20N between 110W and 130W through Thu morning. Seas will likely be below 8 ft across the Pacific waters of Baja California by Fri morning. Please read the latest High Seas Forecast at https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more information on this event. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 08N78W to 02N91W to 02N105W. The ITCZ continues from 02N105W to 06N124W to beyond 04N140W. Widely scattered moderate convection is from 01S to 04N between 102W and 113W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A Gale Warning is in effect for the Gulf the Gulf of Tehuantepec. A large Eastern Pacific Swell Event is ongoing for the NE forecast waters. Please, see the Special Features section for more details. The pressure gradient between a ridge extending across the offshore forecast waters of Baja California and lower pressure along Mexico is supporting moderate to fresh NW to N winds across the Pacific waters of the Baja California Peninsula, the Gulf of California and the entrance of the gulf all the way to the Jalisco offshore waters. Light to gentle winds are elsewhere across the remainder of the Mexican coast, including the region of Tehuantepec. Aside from the seas from the swell event in the special features, seas in the remainder S and SW Mexican offshore waters range between 5 to 7 ft. In the Gulf of California, seas are in the 3 to 5 ft range. For the forecast, large, long-period NW swell affecting the offshore forecast waters of Baja California will continue to propagate southward before diminishing late in the week. High pressure over the Great Basin of United States will support fresh to strong NW to N winds across most of the Gulf of California tonight through Fri morning. These winds are also forecast to filter through the mountains passages in Baja California into the Pacific offshore waters late tonight and Thu, particularly from 25N to 29N E of 118W. The next gap winds event in the Tehuantepec region is expected on Fri. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong winds prevail across the Gulf of Papagayo and downwind to near 90W with seas to 8 ft. Moderate N winds are in the Gulf of Panama where seas are in the 4 to 6 ft range highest S of the Azuero Peninsula. Light to gentle winds are seen elsewhere with seas of 5 to 7 ft primarily in S swell. For the forecast, fresh to strong NE to E winds across the Gulf of Papagayo region will persist through Fri. Strong to near gale force winds and moderate to rough seas are expected at night Fri through Sun. Winds will also increase at night in the Gulf of Panama and downwind to near 04N-05N Fri through Sun. The next strong Tehuantepecer gap wind event should cause large W to NW swell over the Guatemala and El Salvador waters beginning Fri night. REMAINDER OF THE AREA... A ridge extends across the northern forecast waters covering roughly the region N of 18N W of 110W. The pressure gradient between the ridge and the ITCZ to the south supports an area of fresh to strong trades, especially from 06N to 20N west of 130W. Seas are 8 to 10 ft within these winds. Elsewhere winds are moderate or weaker with seas of 5 to 7 ft. For the forecast, fresh to strong trades are forecast to persist over the west-central waters the remainder of the work-week. A cold front will approach the NW corner of the forecast region late on Thu, and move over the N waters likely trough Sun. A low pressure is forecast to develop along the frontal boundary just N of 30N on Fri. The low is forecast to drift southward entering the forecast area by Sat night, and meandering over the NE waters through Sun night. Fresh to strong northerly winds and a new swell event are expected behind the front. $$ Ramos