Clouds and cooler temperatures will persist across the Willamette Valley tonight as onshore flow continues from a system to our north. Inland clouds should begin to break by late Saturday morning as daytime heating progresses. Breezy conditions, with gusts up to 40 mph, are possible in the central Columbia River Gorge today, though winds will decrease significantly Saturday night.
Temperatures will begin to rebound tomorrow across interior valleys, reaching the mid to upper 80s. A significant heat wave is expected Monday and Tuesday, bringing high temperatures into the low 90s for the Willamette Valley and southwest Washington lowlands. There is a chance for temperatures to exceed 100 degrees around Salem and Portland-Vancouver on Monday, with an increased chance on Tuesday.
Overnight lows will also be warm, remaining above the mid 60s, particularly across the central Willamette Valley, Columbia River Gorge, and Portland-Vancouver urban areas. This limited overnight relief from the heat has prompted widespread Moderate HeatRisk across much of northwest Oregon and southwest Washington, with localized Major HeatRisk for the Portland-Vancouver area. We remind everyone to practice heat safety during this period by staying hydrated, wearing light clothing, and scheduling outdoor activities for early morning or late evening…