000 AXPZ20 KNHC 281517 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1517 UTC Fri Feb 28 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 1500 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: High pressure extending from the NW Gulf southward across eastern Mexico is supporting a strong pressure gradient across the Chivela Pass this morning. A recent altimeter pass indicates 8-12 ft seas extend well downstream of the Gulf in NE swell. Strong northerly gales and very large seas will continue over the Tehuantepec region through Sat night, and nocturnal drainage flow will enhance winds to near storm force speeds tonight. Wave heights greater than 20 ft are expected overnight downstream of the Gulf, with NE swell resulting in seas 12 ft or greater reaching as far as 08N100W. Marine interests transiting across or in the vicinity of the Gulf of Tehuantepec should take necessary actions to avoid these hazardous marine conditions. Gulf of Papagayo Gale Warning: A strong pressure gradient across Central America and the western Caribbean is supporting near gale force winds across the Papagayo region this morning. Winds are expected to reach gale force speeds tonight and continue through Sun morning, with seas building to 12-15 ft early Sat. Winds will diminish below gale force Sun afternoon, but remain strong through early next week. Pacific High Seas Gale Warning: A broad mid to upper-level trough west of 140W is expected to induce surface trough development north of the ITCZ along 135W on Sat. The enhanced pressure gradient between this trough and very strong high pressure building NW of the region will result in a brief period of gale force winds Sat night into Sun, as the trough moves westward and eventually passes west of 140W. Associated seas will build to 12-16 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 07N84W to 02N95W to 02N110W to 08N133W to 06N140W. Scattered moderate convection is noted from 05N to 10N between 122W and 126W, and within 120 nm north of the ITCZ west of 133W. 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 winds prevail across the Baja California offshore waters with a weak pressure pattern in place across the region. A low pressure trough is supporting moderate NW winds over the Gulf of California, with locally fresh winds over the northern Gulf. Strong to near gale force SW winds will develop over the northern Gulf of California Sun and Sun night ahead of an approaching cold front. The weakening front will move into the northern waters on Mon, accompanied by strong NW winds and large NW swell with seas greater than 12 ft. This swell will propagate across the southern Baja California waters through early next week 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 through this weekend. Seas will reach 12-16 ft well offshore of Guatemala by Sat morning. 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 through this weekend. Seas will peak around 8-9 ft each day well downstream of the Gulf. 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 west of 125W between the ITCZ and 20N. Seas are generally running 8-11 ft in this region. Elsewhere, a large area of 8-12 ft seas in N to NE swell extends well downstream of the Tehuantepec region. A broad area of strong trade winds will develop north of the ITCZ west of 125W this weekend as very strong high pressure builds NW of the region. A cold front will move into the northern waters Sun through Sun night, 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 night. $$ Reinhart