000 AXPZ20 KNHC 021605 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Fri Apr 2 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 1545 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Overnight Ascat data nicely revealed a large swath of north-northeast gale-force winds, mostly of the 40-45 kt speeds, across the Gulf of Tehuantepec, with winds to 45 kt. These winds are forecast to slowly diminish through tonight, lowering to a peak of 40 kt early Sat and to minimal gale force by early on Sun, before diminishing to just below gale force on Sun afternoon. Wave heights will remain in the 11-17 ft range into Sat. Swell generated by this long- lived event will spread well to the west-southwest of the Gulf of Tehuantepec region through the weekend. Mariners navigating through these waters are urged to use caution due to hazardous marine conditions produced by this gale force gap wind event. Please read the latest HIGH SEAS FORECAST- https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. Volcanic Ash Advisory: Pacaya Volcano in southern Guatemala near 14.4N 90.6W is erupting, producing a plume of volcanic ash into the coastal waters of Guatemala. Although the ash may have thinned out some, some of it may be reaching the ocean surface. This may result in some reduction of the surface visibility. While there have been no reports of volcanic ash reaching the surface or reduced visibilities, mariners are urged to exercise caution. Report 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 axis extends from just west of Costa Rica near 09N85W to 05N90W and 04N96W, where overnight scatterometer data indicates that it transitions to the ITCZ to 05N110W to 05N123W to 04N130W and to beyond the area at 06N140W. Scattered moderate to isolated strong convection is seen within 60 nm south of the ITCZ between 105W-109W. Scattered moderate convection is within 60 nm south of the ITCZ west of 138W, and within 30 nm of the ITCZ between 97W-100W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details on a gale-force wind event in the Gulf of Tehuantepec region. Overnight Ascat data passes depict gentle to moderate winds across the Mexican offshore waters between 99W-119W, with wave heights of 5-6 ft due to mixed SW and NW swell. High pressure building west of Baja California will support fresh northwest 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... Please see the Special Features section above for details on a Volcanic Ash Advisory in effect for the Pacaya Volcano in southern Guatemala. A partial Ascat pass shows a small area of fresh northeast winds along the coast of northern Costa Rica, but since then these winds have increased to fresh to strong speeds. Light to gentle winds are present elsewhere. Wave heights have build to the 7-10 ft in the Papagayo region, and are 5 to 7 ft elsewhere. Fresh to strong offshore gap winds will continue across Gulf of Papagayo region through Sun night. Wave heights will build from northern Costa Rica to Guatemala, due to a combination of swell emanating from from the Papagayo and Tehuantepec gap wind areas mixing with long-period southwest swell. REMAINDER OF THE AREA... Overnight Ascat data passes revealed a narrow band of fresh easterly winds from 06N to 07N between 93W-99W. Wave heights are estimated to be 8 ft in this area. Moderate to fresh trade winds are noted from 08N to 19N west of 115W, with 7 to 8 ft seas. Lighter winds and lower seas exist across the rest of the subtropics. Little change is expected during the next couple of days for most of the forecast area. The only exception will be in the far NW waters, where a low pressure system tracking eastward along 33N will drag a weak cold front into the area. Wave heights produced by this low pressure system and cold front are forecast to build to the 8-11 ft Sun through Mon, with the peak value of 11 ft expected in the far NW corner of the area. $$ Aguirre