000 AXPZ20 KNHC 280313 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Thu Jan 28 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 0000 UTC surface analysis and satellite imagery through 0300 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: High pressure building in the wake of a cold front moving into southern Mexico will tighten the pressure gradient across the Tehuantepec region. Northerly winds behind the front will rapidly funnel through the Chivela Pass, with gale force winds expected tonight. Winds will reach strong gale-force early Thu and then again Thu night. This event will generate very large seas, which will peak around 20 ft Thu night and Fri. Seas generated from this gap wind event will propagate well away from the source region, with seas greater than 8 ft spreading as far west as 110W by Fri night. The gale force winds are forecast to persist through early Sat morning. Looking ahead, another gale force gap wind event is possible Sun night into early next week. Please see the latest High Seas Forecast at http://nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 07N78W to 04N86W to 06N102W. The ITCZ extends from 06N112W to 05N121W to beyond 03N140W. Scattered moderate isolated strong convection is noted from 05N to 09N between 111W and 116W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for details on a Gale Warning for the Gulf of Tehuantepec region. Strong northerly winds over the southern Gulf of California are expected to diminish overnight. Moderate to fresh winds prevail off Baja California Sur southward to off Cabo Corrientes. Light to gentle winds prevail elsewhere. NW swell is producing seas in the 7-9 ft range west of the Baja California peninsula southward to offshore Cabo Corrientes, with seas in the 4-7 ft range elsewhere over the open waters off Mexico. The NW swell across the area will continue to diminish through Thu. A weakening cold front approaching Baja California Norte Thu night will usher in another set of large NW swell that will spread southward W of the Baja California peninsula through Sat morning. This swell will subside this weekend. Another set of NW swell will reach the waters off Baja California Norte Mon night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Scatterometer data indicates moderate to fresh winds across the Gulf of Papagayo, with light to gentle winds elsewhere. Seas are in the 5-7 ft range in Gulf of Papagayo, and 3-5 ft elsewhere. The offshore winds across the Papagayo region will become fresh to strong through Sat night. Fresh northerly winds will pulse in the Gulf of Panama through Thu, becoming fresh to strong Thu night through Fri night. Gentle to moderate winds are expected elsewhere. Large seas generated by strong winds in the Tehuantepec region will spread into the offshore waters of Guatemala and El Salvador Thu night through early Sat. REMAINDER OF THE AREA... A cold front extends across the northwest part of the discussion area from 31N127W to 26N140W. Fresh to strong winds are noted on either side of the front, with seas to 16-18 ft. Large NW swell associated with the front will spread south-southeastward across the forecast region, with seas peaking near 19 ft along 30N overnight. The gradient between weak high pressure analyzed near 27N120W and lower pressures near the ITCZ is supporting fresh NE trade winds north of the ITCZ to 20N, west of 120W. Seas in this area are in the 8 to 9 ft range in a mix of NW swell and NE to E wind waves. The pressure gradient will weaken tonight and Thu as the area of high pressure weakens further. Another set of NW swell will propagate into the NW waters Sunday. $$ Mundell