000 AXPZ20 KNHC 030314 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sat Oct 3 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... Powerful Hurricane Marie is centered near 17.5N 125.7W at 03/0300 UTC moving NW or 315 degrees at 8 kt. This general motion is expected to continue through most of the weekend. A turn toward the west-northwest is possible by early next week. Estimated minimum central pressure is 948 mb. Maximum sustained wind speed is 115 kt with gusts to 140 kt. Marie is a category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale. Some fluctuations in intensity are possible through tonight, followed by weakening beginning on Saturday. This weakening trend will continue into early next week. 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: A ridge across the western Gulf of Mexico and eastern slopes of the Sierra Madre Mountains in Mexico combined with Tropical Storm Gamma in the NW Caribbean will continue to support fresh to strong northerly winds over the Bay of Campeche. These winds are funneling through the Chivela Pass into the Gulf of Tehuantepec, producing strong gale force winds of 35-40 kt in the Tehuantepec region. These gap winds are forecast to persist into Sat, with minimal gale conditions prevailing through Sun. Winds are forecast to increase again to 35-40 kt Sun night and Mon as T.S. Gamma moves just N of the Yucatan Peninsula. Seas will peak near 16-17 ft tonight into Sat. 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. ...TROPICAL WAVES... The tropical wave that spawned T.S. Gamma now extends along 88W N of 03N. The wave is helping to induce some convective activity over northern Central America. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 11N86W to 11N90W to 08N100W to 11N108W, then resumes W of Hurricane Marie near 10N127W to 09N136W. The ITCZ is from 09N136W to beyond 10N140W. Scattered moderate convection isolated strong convection is noted from 06N to 11N between 82W and 88W, and from 12N to 15N between 98W and 102W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see above 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. By Mon night, a ridge will establish again over the area, bringing gentle to moderate NW winds. Seas generated by Hurricane Marie will continue to spread across the waters W of Baja California into Sat. Gentle southerly winds are expected in the Gulf of California into the start of next week. 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 the start of next week. REMAINDER OF THE AREA... Please see Special Features section above for more information on Category Four Hurricane Marie. Outside of Major Hurricane Marie, a weak ridge prevails over the NW corner of the forecast area. The pressure gradient between this ridge and Marie is maintaining gentle to moderate winds N of the monsoon trough to about 25N, and gentle to moderate winds S of the monsoon trough. The large size of Hurricane Marie will generate a large area of seas greater than 8 ft which will spread well away from the cyclone center. By Saturday, seas greater than 8 ft will cover much of the waters N of 10N and W of 115W. Long period SE swell from the Southern Hemisphere is forecast to reach the equator by Mon. A broad area of low pressure is expected to form several hundred miles southwest of the coast of southwestern Mexico this weekend. Some development of this system is possible early next week while it moves westward at 5 to 10 kt. Another area of low pressure could form south or southeast of the Gulf of Tehuantepec early next week. Gradual development of this system will be possible thereafter while it drifts near or south of southern coasts of Mexico and Guatemala. Marine guidance suggests increasing winds across the offshore waters of Guatemala and El Salvador early next week. The latest Tropical Weather Outlook states that these systems have a low chance of tropical cyclone formation through 5 days. $$ GR