000 AXPZ20 KNHC 291501 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1500 UTC Sat Feb 29 2020 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 1430 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: High pressure centered over the central Gulf of Mexico is supporting a tight pressure gradient across the Isthmus of Tehuantepec. Overnight scatterometer data revealed northerly gales up to 45 kt across the area, and peak seas were recently analyzed to 21 ft downstream of the Gulf. Strong gales and large seas will continue through tonight, then quickly diminish on Sun as high pressure weakens and shifts eastward. Looking ahead, another gale force gap wind event is possible Wed night as another strong cold front crosses the Gulf of Mexico. Gulf of Papagayo Gale Warning: A strong pressure gradient across Central America and the western Caribbean is likely supporting gale force winds over the Papagayo region this morning. Peak seas were recently analyzed to 12 ft downstream of the Gulf. Marginal gales are expected to continue into early Sun, then diminish by Sun afternoon. Seas are expected to build to 14 ft late tonight. Looking ahead, strong winds will continue over the region through early next week, pulsing to near gale force each night. Pacific High Seas Gale Warning: A broad mid to upper-level trough west of 140W has induced the development of a surface trough between 135W and 140W per overnight scatterometer data. Scattered moderate isolated strong convection is noted from 09N to 14N west of 134W in association with this feature. The tightening pressure gradient between the trough and very strong high pressure building northwest of the region is supporting strong winds that will increase to marginal gale force by tonight. These winds will continue into early Sun, then shift west of 140W as the trough axis moves westward. Associated seas will build to 12-17 ft within the strongest winds. Please read the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03/HSFEP2 NHC or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The ITCZ extends from 05N88W to 02N94W to 02N121W to 06N125W to 07N134W. Scattered moderate convection is noted from 02S to 01N east of 83W, and within 90 nm of the ITCZ between 95W and 109W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for more details about a gale warning in the Gulf of Tehuantepec region. Gentle to moderate winds prevail across the Baja California offshore waters between an offshore high pressure ridge and a low pressure trough near the Gulf of California. A mid to upper-level trough will approach the area from the north tonight and drive a cold front southward that will cross the Baja California region through early next week. Fresh to strong SW to W gap winds will develop over the northern Gulf of California starting tonight, reaching near gale force by Sun night as seas build to near 8 ft. Expect strengthening NW winds and building seas over the Baja offshore waters following the front, with seas greater than 8 ft expected across the Baja offshore waters by Tue. Wave heights will peak around 16-18 ft near Guadalupe Island late Mon. The associated NW swell will continue propagating southward through Wed while gradually decaying. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Please see the Special Features section above for more details about a gale warning in the Papagayo region. Large NW swell generated by the Tehuantepec gales will combine with easterly swell from the Papagayo region to maintain rough seas offshore of Guatemala and El Salvador this weekend. Seas will reach as high as 15 ft well offshore of Guatemala this afternoon. Wave heights will subside early next week as the gap winds diminish. Elsewhere, strong winds will pulse over and downstream of the Gulf of Panama this weekend, then remain fresh Mon through Wed. Seas will peak around 9-10 ft well downstream of the Gulf this weekend, then remain 8 ft or less through mid week. REMAINDER OF THE AREA... Please see the Special Features section above for more details about a Pacific high seas gale warning. Fresh to locally strong trade winds prevail W of 120W north of the ITCZ to 20N. Seas are generally 8-10 ft in this region. Elsewhere, a large area of 8-12 ft seas in N swell extends well downstream of the Tehuantepec region, as far south as 01N100W. An area of 8-10 ft seas in NW swell over the NW portion will gradually spread southeastward through Sun. A cold front will move into the waters north of 20N Sun through Mon, followed by strengthening NW winds and building seas. Associated NW swell will move southward across the region through early next week, with seas 12 ft or greater expected north of 25N east of 130W by Mon. Marine conditions will gradually improve Tue through Wed night as residual swell decays over the region and high pressure weakens north of the area, allowing the pressure gradient to relax over the high seas. $$ Reinhart