000 AXPZ20 KNHC 011533 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Thu Apr 1 2021 Tropical Weather Discussion for the eastern Pacific Ocean from the Equator to 32N, east of 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. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Strong high pressure, in the wake of a cold front over the Gulf of Mexico, is building southward across the south-central U.S. and Mexico. The tight pressure gradient between the high and lower pressure to the south has set up a late-season strong gale force gap wind event across the Gulf of Tehunatepec. Winds are expected to increase to near 45 kt over the gap later today or tonight and continue into Sun. Wave heights will build to 10-15 ft later today and remain high into Sun. Swell generated by this event will spread well to the southwest and west of the Gulf of Tehuantepec region through the weekend. Mariners navigating through these waters are urged to use caution as these impending conditions are likely to lead to hazardous marine conditions. Please read the latest HIGH SEAS FORECAST- https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. Volcanic Ash Advisory: The Picaya Volcano in southern Guatemala located near 14.4N 90.6W is currently erupting and is producing a plume of volcanic ash observed to be spreading out across the offshore waters of Guatemala. The ash may reaching the surface of the ocean, and may be reducing visibility to some extent. While there have been no reports of volcanic ash reaching the surface or reduced visibilities, mariners are still urged to exercise caution and report and observations to the National Hurricane Center by calling 305-229-4425. Please read the latest HIGH SEAS FORECAST- https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details on both the Gale Warning and on the Volcanic Ash Advisory. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough extends from 10N85W to 06N91W. The ITCZ continues from 06N91W to 06N110W to 02N140W. Scattered moderate to isolated strong convection is noted from 05N to 07N between 81W and 86W and from 04N to 07N between 106W and 113W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details on the ongoing gap gale-force wind event in the Gulf of Tehuantepec region and on the Picaya Volcano. Gentle to moderate winds continue throughout the Mexican offshore waters north of 20N. Seas are 3 to 5 ft north of 20N, except 5 to 7 ft in NW swell off Baja California Norte. South of 20N, seas are 5 to 7 ft in SW swell. For the forecast, high pressure building west of Baja California will allow fresh NW winds off Baja California Norte this weekend. Gentle to moderate NW winds will persist elsewhere across the Mexican offshore waters outside of the Tehuantepec region. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... A Volcanic Ash Advisory is in effect for the Picaya Volcano in southern Guatemala. See Special Features above. Fresh to strong northeast to east winds are occurring across the Gulf of Papagayo area due to high pressure building to the north of the area. Seas are likely up to 10 ft in the plume of gap winds, with a component of longer-period SW swell. Fresh N gap winds are likely active across the Gulf of Panama, with a plume reaching as far south as 05N in 5 to 7 ft seas. Elsewhere light to gentle winds continue over the Central American offshore waters with 3-5 ft wave heights. For the forecast, fresh to strong offshore gap winds will continue across Gulf of Papagayo region through Sun night. Seas will build from northern Costa Rica to Guatemala by Thu, due to seas generated from the Papagayo and Tehuantepec gap wind areas mixing with longer-period SW swell. REMAINDER OF THE AREA... Trade winds are mostly moderate across the area, except for slightly stronger winds across the deep tropics west of about 130W. Despite the lack of strong winds, seas are elevated to 7 to 10 ft across the deep tropics due to mixed swell. Lighter winds and lower seas exist across the subtropics, where the pressure gradient is more relaxed. Little change is expected in the overall pattern during the next couple of days. The models show a low pressure system moving across the far northwestern waters late this weekend, that could increase winds there. $$ Cangialosi