000 AXPZ20 KNHC 050317 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Mon Oct 5 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 0000 UTC surface analysis and satellite imagery through 0300 UTC. ...SPECIAL FEATURES... Marie is downgraded to a Tropical Storm at 05/0300 UTC. At this time, it is centered near 20.6N 130.1W moving NW at 7 kt. This general motion is expected to continue for the next few days, with a slight decrease in forward speed by the middle of the week. Estimated minimum central pressure is 988 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Marie is forecast to become a tropical depression or remnant low by Wednesday. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPEP3.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMEP3.shtml for more details. Gulf of Tehuantepec Gale Warning: Fresh to strong northerly winds between a ridge across the western Gulf of Mexico and T.S. Gamma now located just N of the Yucatan peninsula will continue to support a gap wind event across the Tehuantepec region. Gale force winds are expected to blow across the Gulf of Tehuantepec and downwind to near 13N-14N through early Tue morning. Seas will peak again near 15-16 ft tonight into Mon morning. This gap wind is forecast to persist into mid-week. Please read the latest NWS High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. Showers and thunderstorms are showing some signs of organization in association with an area of low pressure located several hundred miles south of the southwestern coast of Mexico. A 1008 mb low pressure is analyzed near 11N105W. Environmental conditions appear conducive for some additional development, and a tropical depression could form during the next couple of days while it drifts northwestward. This system has a medium chance of tropical cyclone formation through 48 hours. ...TROPICAL WAVES... A tropical wave extends along 98W N of 03N, moving W at 5 to 10 kt. Scattered moderate isolated strong convection is noted from 09N to 12N between 92W and 98W, and from 11N to 15N between 98W and 100W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 11N86W to 13N90W to 10N98W to a 1008 mb low pres near 11N105W to 10N115W to 12N120W, then resumes W of T.S. Marie near 12N134W to beyond 08N140W. Scattered moderate isolated strong convection is observed from 07N to 10N between 81W and 85W, from 10N to 14N between 103W and 111W, and from 11N to 15N between 118W and 121W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see Special Features section for more on the ongoing Gulf of Tehuantepec Gale Warning. Elsewhere, mainly light to gentle winds will dominate the offshore forecast waters of Baja California under a weak pressure gradient. A ridge will establish again over the area on Mon, bringing moderate NW winds, mainly offshore Baja California del Norte. Light to gentle southerly winds are expected in the Gulf of California through Tue. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Moderate to locally fresh southwesterly winds are expected S of the monsoon trough with mainly light to gentle winds N of it. Seas generated by the gale-force gap winds in the Tehuantepec region will continue to propagate across the offshore waters of Guatemala and El Salvador into Tue night. Looking ahead, an area of low pressure could form south-southeast of the Gulf of Tehuantepec in a couple of days. Development, if any, of this system should be slow to occur while it moves slowly northward toward the coasts of Mexico and Guatemala. This system has a low chance of tropical formation in the next 5 days. REMAINDER OF THE AREA... Please see Special Features section above for more information on Tropical Storm Marie that is rapidly weakening over cooler waters and low pressure well southwest of southern Mexico that could develop into a tropical depression over the next few days. Outside of Marie, gentle to moderate winds are occurring N of the monsoon trough to about 28N, and gentle to moderate winds prevail S of the monsoon trough. Currently, seas greater than 8 ft, generated by Marie cover most of the waters N of 10N and W of a line from 30N120W to 10N123W. Long period SE swell from the Southern Hemisphere is forecast to reach the equator late tonight. Tropical Storm Gamma located north of the Yucatan Peninsula is expected to produce heavy rainfall for several days over portions of southeastern Mexico, the Yucatan Peninsula, and Central America. This rainfall could result in life-threatening flash flooding and mudslides, particularly in the mountainous regions of southeastern Mexico and Central America. $$ GR