Eastern Pacific Tropical Weather Discussion
832 AXPZ20 KNHC 280322 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Wed Oct 28 2026 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 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 0000 UTC. ...SPECIAL FEATURES... Tropical Storm Vance is centered near 17.3N 108.4W at 28/0300 UTC, moving northwest at 7 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Peak seas are currently around 12-13 ft or 4 m. Vance remains a sheared tropical cyclone with convection limited to the SE side of the system. Numerous moderate to strong convection is noted within 180 nm in the SE semicircle of Vance. Additional isolated to widely scattered moderate convection is noted on satellite imagery between 120 nm and 360 nm in the N quadrant. Vance is moving toward the northwest. A gradual turn toward the north is expected through midweek. Little change in strength is forecast during the next couple of days, and Vance could become a post-tropical cyclone during this time if it is unable to sustain organized convection. Periods of heavy rainfall associated with Vance will impact portions of western Mexico during much of this week. This rainfall may produce flooding and mudslides across central and southern Sinaloa, western Durango, and northwestern Nayarit, especially in areas along steep terrain. Swells generated by Vance will affect coastal portions of southern, southwestern, and west-central Mexico during the next few days. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest Vance NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N75W to 06N85W to 10N99W well SE of Tropical Storm Vance. It resumes well SW of Vance from 08N113W to 1010 mb low pressure near 07N136W to 05N140W. Scattered moderate isolated strong convection is noted from 03N to 10N between 77W and 89W, and from 00N to 10N between 132W and 140W. Scattered moderate convection is noted from 02N to 07N between 100W and 105W, and from 00N to 04N between 112W and 119W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for information on Tropical Storm Vance. Northerly winds in the Gulf of Tehuantepec are fresh to near gale force with seas to rough. Light to gentle winds, and slight to moderate seas, prevail in the Gulf of California. Elsewhere, outside of Vance and the Gulf of Tehuantepec, winds are mainly moderate or weaker, with moderate seas, over the open waters off Mexico. For the forecast, Tropical Storm Vance will move to 18.5N 108.7W Wed morning, 20.2N 108.5W Wed evening, become post-tropical and move to 21.7N 108.1W Thu morning, 23.5N 107.7W Thu evening, weaken to a remnant low near 25.3N 107.0W Fri morning, and dissipate Fri evening. Winds in the Gulf of Tehuantepec will pulse fresh to near gale force through Thu night, then pulse moderate to fresh thereafter. A developing low pressure and frontal system may impact the Baja California Peninsula waters late in the upcoming weekend with the potential for increasing winds and building seas. Moderate or weaker winds and moderate seas will prevail otherwise. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate or weaker winds and moderate seas generally prevail. For the forecast, fresh NE winds over and downstream of the Gulf of Papagayo will pulse to moderate to fresh speeds through the end of the week and into the upcoming weekend, locally strong at times this weekend. Moderate to fresh northerly winds will pulse in the Gulf of Panama through the end of the week, locally strong at times through mid-week. Moderate or weaker winds and moderate seas will continue elsewhere, except mainly slight nearshore Colombia. Seas may briefly build to rough in SW swell S of the Equator by the end of the week. ...REMAINDER OF THE AREA... See Special Features section above for information on Tropical Storm Vance. A slow moving cold front is over the far NW waters, with scattered moderate and isolated strong convection ahead of the front. Fresh to strong winds and rough seas are within 60 nm east of the front. High pressure prevails elsewhere N of about 20N. The pressure gradient between the area of high pressure and the monsoon trough is supporting moderate to locally fresh tradewinds N of the monsoon trough to near 20N and between 120w and 136W. Moderate seas are found over these waters. Moderate to fresh winds, and rough seas are found S of 02N between 100W and 120W. Across the remainder of the waters, winds are moderate or weaker with moderate seas. For the forecast, Tropical Storm Vance will move to 18.5N 108.7W Wed morning, 20.2N 108.5W Wed evening, become post-tropical and move to 21.7N 108.1W Thu morning, 23.5N 107.7W Thu evening, weaken to a remnant low near 25.3N 107.0W Fri morning, and dissipate Fri evening. Fresh to locally strong SE to S winds over the NW part of the area will diminish to mostly fresh speeds on Wed. Cross equatorial SW swell will spread northward through late Wed, building seas to 7-10 ft S of 04N between 105W and 128W by late Wed night, while mixing with NE swells generated by Vance. These rough seas are expected to linger through at least Fri night, likely subsiding by the start of the weekend. Elsewhere, moderate or weaker winds and moderate seas will persist through at least mid- week. A developing low pressure and frontal system may impact the waters N of 20N by the end of the week into the upcoming weekend with the potential for increasing winds and building seas as the system shifts eastward.