000 AXPZ20 KNHC 122120 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2120 UTC Wed Feb 12 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A cold front over the western Gulf of Mexico will cross the southwestern Gulf of Mexico tonight. Strong winds behind the front will funnel across the Isthmus of Tehuantepec, with gale force winds expected over the Gulf of Tehuantepec late Thu night. Gales are likely to persist through the weekend, with the strongest pulses during the overnight and early morning hours in conjunction with nocturnal drainage flow. Refer to the latest High Seas Forecast FZPN03 KNHC/HSFEP2 issued by the National Hurricane Center, and the website https://www.nhc.noaa.gov/text/MIAHSFEP2 for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 04N77W to 03N80W to 03N85W. The ITCZ extends from 03N85W to 07N100W to 04N107W to 06N120W to 05N140W. Scattered moderate convection is noted within 120 nm of the ITCZ between 98W and 102W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for information on expected gale conditions in the Gulf of Tehuantepec. Weak high pressure extends across the waters north of 20N this afternoon. Recent scatterometer data showed moderate northerly winds over the Baja California Sur waters and the entrance to the Gulf of California, with fresh winds noted along the coast of Sinaloa. Elsewhere, this pattern is generally supporting gentle to moderate breezes across most of the Mexican offshore waters. Earlier altimeter data highlighted 8 ft seas in residual NW swell west of the Revillagigedo Islands. A weakening cold front or trough may cross the northern waters Fri night into Sat. High pressure building in the wake of the front will support fresh winds over the central and southern Gulf of California Sat night through early next week. NW swell will move across the Baja California offshore waters late Sat through Sun, with seas expected to build to 8 ft off Baja California Norte. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Earlier scatterometer data indicated fresh to strong NE to E winds over the Papagayo region, with fresh winds extending well downstream into the offshore waters off Guatemala and El Salvador. Elsewhere, moderate northerly winds were noted over and downstream of the Gulf of Panama. Strong to near gale force winds will prevail over the Papagayo region through Mon night, with a large area of fresh to strong winds expected well downstream of the Gulf of Papagayo each day. Swell generated by the Papagayo gap wind event, and later from the Tehuantepec region, is expected to impact the offshore waters off Guatemala and El Salvador through early next week. The highest seas are expected this weekend as combined seas build to 8-11 ft in these waters. Fresh N winds will prevail over and downstream of the Gulf of Panama through Fri, then pulse to strong speeds Fri night through early next week. REMAINDER OF THE AREA... High pressure building over the waters north of 20N is supporting fresh to locally strong trade winds between the ITCZ and 20N west of 130W, as noted in earlier scatterometer passes. Concurrent altimeter data indicated wave heights around 8-10 ft in this region, likely in mixed NE to E wind waves and residual NW swell. Farther east, showers and thunderstorms persist near the ITCZ between 98W and 102W. This surface pattern will persist through late week with little change in marine conditions. By this weekend, a mid to upper- level low will cutoff west of 125W, and global models indicate an associated surface trough will form roughly between 120W and 130W. A tightening gradient between this trough and high pressure over the northern waters will allow trade winds to increase east of the trough axis. $$ Reinhart