000 AXPZ20 KNHC 072113 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Wed Oct 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 1800 UTC surface analysis and satellite imagery through 2020 UTC. ...SPECIAL FEATURES... Post-Tropical remnant low Marie with a pressure of 1005 mb is located near 24N137W. Scattered moderate convection is sheared off in the NE quadrant between 60 nm and 360 nm. Recent scatterometer winds showed gale force winds and a gale warning has been issued through this evening. The scatterometer showed even stronger winds but these are likely rain-inflated. Seas are 10-15 ft in the area of gale force winds. Fresh to near gale winds will persist once the gale warning ends later tonight, then will gradually diminish. A large surrounding area of seas of 8 ft or greater will gradually subside as well. The remnant low will shift W of 140W by early Fri. Please read the latest High Seas Forecast issued by the National Hurricane Center at: https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. Tropical Depression Norbert is centered near 13.4N 107.1W at 07/2100 UTC moving S at 2 kt. Estimated minimum central pressure is 1006 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Scattered moderate convection is noted within 45 nm in the W quadrant and between 45 nm and 120 nm in the E quadrant of Norbert. Little motion is expected tonight, with a southwestward drift expected on Thu, and a slow motion toward the W-NW or NW expected Fri and Sat. Little change in strength is forecast during the next few days. Please read the latest NHC Public Advisory at: https://www.nhc.noaa.gov/text/MIATCPEP4.shtml and Forecast/Advisory at: https://www.nhc.noaa.gov/text/MIATCMEP4.shtml for more details. A 1009 mb low pressure area is located near 121.5N125W. Scattered moderate to strong convection is noted within 150 nm in the NW quadrant of the low. Fresh to strong winds are noted in the SE semicircle. Similar winds were noted in the NW quadrant but these are likely rain-inflated. Seas are up to 11 ft in the area of strongest winds. Further development of this system is possible and a tropical depression could form during the next few days while it moves slowly northwestward at around 5 kt. This low has a medium chance for tropical cyclone development during the next 48 hours. Please read the latest NHC Tropical Weather Outlook at https://www.nhc.noaa.gov/text/MIATWOEP.shtml for more details. ...TROPICAL WAVES... A tropical wave is along 87W N of 03N to near the Gulf of Fonseca, moving W at around 10 kt. Scattered moderate convection is noted from 03N to 11N between 85W and 89W. A tropical wave is along 102W from 04N to 16N, moving W at around 10 kt. Some isolated showers and thunderstorms are noted just to the E of the wave axis. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northern Colombia near 09N75W to 12N87W to low pressure near 11N94W to 12N99W, then resumes SW of Norbert near 13N109W to 14N118W to low pressure near 12.5N125W to 12N137W. The ITCZ extends from 12N137W to 11N140W. Scattered moderate and isolated strong convection is noted from 03N to 10N between 77W and 84W, from 10N to 13N between 105W and 115W, and also from 10N to 15N between 115W and 124W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see Special Features section for details on Tropical Depression Norbert. Outer seas of 8 to 10 ft will shift northwestward across the far outer offshore waters of southwestern Mexico to the W of Manzanillo through Fri. A surface trough is analyzed from 26N113W to 22N116W while weak high pressure is building NW of the trough. The trough will linger through the end of the week and into the weekend with moderate to locally fresh NW-N winds NW of the trough, and light to gentle winds SE of the trough N of 20N. Combined seas will be mainly 4-7 ft in mixed long period S and NW swell. Seas will build offshore of Baja California Norte early next week in fresh NW swell. Meanwhile, mainly light to gentle southerly winds are expected in the Gulf of California during the next several days. Strong northerly winds across the Gulf of Tehuantepec will diminish this evening, while associated seas to 8 ft subside. More tranquil marine conditions are forecast for the remainder of the forecast period. 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 through the next several days. Combined seas will be mainly 4 to 7 ft in mixed long period S and NW swell, subsiding slightly this weekend. REMAINDER OF THE AREA... Please see Special Features section above for details on Tropical Depression Norbert, on low pressure near 12.5N125W, and on the Gale Warning associated with the remnant low of Marie. A large area of 8 to 10 ft seas in combined long period southerly and northerly swell surrounds the low near 12.5N125W and extends across the waters S of 15N between 100W and 130W. These seas will gradually decay through the end of the week, becoming confined to S of the equator. S-SW monsoonal flow may freshen S of the monsoon trough between 95W and 115W through the end of the week, helping to build seas to 8 to 9 ft. A set of fresh NW swell will spread into the northern discussion waters early next week with seas building to 8 to 9 ft. $$ Lewitsky