000 AXPZ20 KNHC 071550 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1253 UTC Tue Jan 7 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 1530 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A tight pressure gradient is between the Gulf of Mexico and the eastern Pacific south of Mexico. Gale force northerly winds are over the Gulf of Tehuantepec with 12 ft seas. Winds are forecast to further increase to strong gale, just shy of minimal storm force, by this evening. Seas will quickly build to around 23 ft by Wed. Gale force winds will then persists through Thu before diminishing. There is a potential of another round of gale force gap winds by Sat night. Gulf of Papagayo Gale Warning: High pressure will build toward northern Central America today, increasing the pressure gradient over Nicaragua and Costa Rica. This will cause gale force NE to E winds to develop in the Gulf of Papagayo tonight through Wed evening. Seas 8 to 12 ft can be expected during this period. Winds and seas will only subside slightly, with strong winds prevailing through the weekend. Please read the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details on both Gale Warnings. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough axis extends from 1011 mb low pressure over northern Colombia near 09N75W to low pressure near the W coast of Colombia near 03N80W to 03N84W to 05N95W to 05N99W. The ITCZ then continues from 05N99W to 06N111W, then resumes from 07N115W to 07N137W. Scattered moderate convection is from 05N to 12N between 110W and 115W. Isolated moderate convection is from 05N to 12N between 124W and 136W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See the Special Features section for more details about the Gale Warning for the Gulf of Tehuantepec. Gulf of California: The pressure gradient between high pressure over the SW U.S. and low pressure trough over NW Mexico is tight, leading to strong NW winds in the Gulf of California. Seas are less than 8 ft. These winds will diminish this evening. The next marine weather event is not expected until Thu night over the north Gulf. The central and southern Gulf will have strong winds Fri and Sat. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... See the Special Features section for more details about the Gale Warning for the Gulf of Papagayo. Large NW swell generated by gales in the Gulf of Tehuantepec will impact waters off Guatemala tonight through Thu. Seas will build to between 8-14 ft during this time period. Gulf of Panama: Pulses of fresh northerly winds are expected to dominate the Gulf of Panama and waters N of 05N through the remainder of the week. Elsewhere, gentle to moderate S to SW flow will continue over the offshore waters of and S of Costa Rica through the week and into the upcoming weekend. REMAINDER OF THE AREA... High pressure of 1034 mb is centered N of the area near 34N150W with ridging extending SE toward 20N120W. A surface trough is embedded in the ITCZ, extending from 14N137W to 06N140W. A tight pressure gradient exists between these two features, leading to fresh to strong trade winds over the W central waters. Seas are also up to 8-10 ft in this area. This trough is forecast to push W of 140W through the middle of the week. Another surface trough extends from 12N113W to 05N113W moving W along the ITCZ. Tradewinds are forecast to strengthen and expand by the end of the week into the upcoming weekend, and with an increasing fetch resultant seas will build to up to 11-13 ft. New swell will arrive N of 15N and E of 125W Wed afternoon and continue through Sun, likely bringing 8-12 ft seas to the region. $$ Formosa