
A child plays at the splash pad at Willamette Park in West Linn, Ore. on June 13, 2026.
Saskia Hatvany / OPB
People across Oregon’s Willamette Valley and Southwest Washington are likely to face extreme heat early this week.
According to the National Weather Service, there is at least a 70% chance that temperatures will exceed 90 degrees across the region after rebounding into the low-to-mid 80s on Sunday afternoon.
The weather agency has issued a heat advisory from 11 a.m. Monday through 11 p.m. Tuesday for much of northwest Oregon and Southwest Washington. High temperatures could reach 100 degrees in the Portland-Vancouver metro area, the Willamette Valley and the Columbia River Gorge on Monday.
Temperatures are expected to begin easing Wednesday, with highs likely falling into the upper 80s and low 90s. However, forecasters say there remains a 20% to 40% chance of temperatures reaching 95 degrees or higher in the Portland-Salem corridor.
Officials urge people to stay hydrated, limit strenuous outdoor activity during the hottest parts of the day and take frequent breaks if working outside.
Anyone seeking relief in rivers or streams should use caution, as waterways may be dangerously cold and fast-moving despite the hot weather. Heat-related illnesses, and even deaths, increase significantly during extreme heat events.