000 AXPZ20 KNHC 192157 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Fri Feb 19 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 1800 UTC surface analysis and satellite imagery through 2145 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Very strong high pressure building southward along the eastern slopes of the Sierra Madre Mountains is resulting in strong Gulf of Tehuantepec gale gap winds These winds are producing wave heights in the range of 14-22 ft. It is possible that these winds, may at times, briefly attain wind gusts to storm force through tonight before they begin to diminish Sat night. As the high pressure gradually begins to weaken, the resultant tight gradient will begin to slacken allowing for these winds to diminish to minimal gale force early on Sun and to below gale force during Sun afternoon. Wave heights produced by these winds are are forecast to lower to the range of 10-13 ft early on Sun. Mariners planning to navigate across or near the Gulf of Tehuantepec region through Sat night should be aware of this significant wind event as it could lead to hazardous marine conditions. Large seas generated from this strong Gulf of Tehuantepec gap wind event will spread well away from the Tehuantepec area, with seas 8 ft or greater reaching 107W by Sun. Please read the latest NWS high seas forecast issued at the National Hurricane Center at website: https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from a 1011 mb low over northwestern Colombia southwestward to across southern Costa Rica and to 09N84W to 04N91W and to 03N103W, where latest scatterometer data indicates that it transitions to the ITCZ to 06N117W to 06N126W to 05N130W and to beyond 04N140W. Scattered moderate convection is noted from 06N to 11N between 107W-113W, from 06N-11N between 116W-123W and from 06N-10N between 123W-128W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see above for more information on the ongoing Gulf of Tehuantepec gale warning. ASCAT data passes from this morning shows moderate to fresh northwest winds west of the Baja California Peninsula along with waves of 8-9 ft. These winds will diminish to mainly moderate speeds by this evening, with wave heights lowering to less than 8 ft. Fresh to strong winds are over the central and southern Gulf of California as noted in the latest ASCAT pass over that region. These winds will diminish to light to gentle speeds early on Sat, but are expected to materialize over just about the entire Gulf from Sun through mid-week. Wave model guidance is indicating that wave heights could reach 9 ft in the northern Gulf on Wed and Wed night and also 9 ft in the central Gulf section on Sun night. These winds could funnel through the Baja California passages into the Pacific waters at times. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Winds will pulse to fresh to strong in the Gulf of Papagayo region each night during the next several days. Winds will pulse to fresh to locally strong speeds across the Gulf of Panama through mid-week. Light to gentle winds will continue elsewhere. Large seas generated by a strong winds in the Gulf of Tehuantepec will propagate through the offshore waters of Guatemala and El Salvador through early Sun. REMAINDER OF THE AREA... The combination of very strong high pressure of 1037 mb well north of the area and lower pressures near the ITCZ is supporting moderate to fresh trade winds across the deep tropics west of 120W. Strong high pressure will build north of the area this weekend leading to strong trade winds and higher wave heights over much of the area west of 120W Sun through Mon. Northwest swell continues to subside over the area. A new set of northerly swell will propagate through the north-central and northeast waters on Sat and continue through early next week as it shifts westward while subsiding some. Yet another set of northerly swell will begin to move through the far northeast waters Tue night through Wed night. $$ Aguirre