000 AXPZ20 KNHC 050918 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Tropical Storm Marie is centered near 20.8N 131.1W at 05/0900 UTC moving WNW at 8 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 993 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. Satellite images show the exposed low-level circulation well to the southwest of any remaining deep convection. 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 locally strong northerly winds between a ridge across the western Gulf of Mexico and T.S. Gamma located 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 tonight into early Tue morning. Seas will peak near 15-16 ft today, and near 13-14 ft tonight. This gap wind event will continue on Tue and Tue night with northerly winds below gale force. 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 still showing signs of organization in association with an area of low pressure located several hundred miles south of the southwestern coast of Mexico. Environmental conditions appear conducive for additional development, and a tropical depression will likely form during the next day or two while the system drifts northwestward. The latest Tropical Weather Outlook states that this system has a high chance of tropical cyclone formation through 48 hours. Refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...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 11N between 92W and 98W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 11N86W to 12N90W to 09N97W to a 1007 mb low pres near 11.5N105W to 12N112W to 12N123W, then resumes W of T.S. Marie near 12N131W to beyond 08N140W. Scattered moderate to isolated strong convection is observed from 10N to 13N between 108W and 112W. Scattered moderate convection is from 06N to 10N between 81W and 86W, from 10N to 13N between 103W and 107W, and from 08N to 15N between 120W and 123W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see Special Features section for more on the long duration Tehuantepec gap wind event. As Marie continues to move westward, a ridge will finally establish today over the offshore waters of Baja California bringing gentle to moderate NW-N winds with seas of 5-7 ft. As it is normal for this time of the year, mainly light to gentle southerly winds are expected in the Gulf of California during the next several days. A broad area of low pressure has formed a few hundred miles south-southeast of the Gulf of Tehuantepec. Some slight development of this system is possible over the next couple of days while it moves slowly northward. Upper-level winds are forecast to become unfavorable for development by Thursday. 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. 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 while moderate to locally fresh 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 20N124W to 10N130W. Long period SE swell from the Southern Hemisphere is forecast to reach the equator later today. Tropical Storm Gamma located north of the Yucatan Peninsula is expected to produce heavy rainfall through midweek over portions of southeast Mexico, including the Mexican states of Yucatan, Campeche, and Tabasco. This rainfall could result in significant flash flooding. $$ GR