Oregon – Cold air sits heavy across the Willamette Valley this morning, pooling near the ground and refusing to move. Streetlights glow over frosted sidewalks, and exhaust hangs longer than usual in the still air.
The National Weather Service has issued an Air Stagnation Advisory for central and southern portions of the Willamette Valley, including Portland, Salem, Albany, Corvallis, Eugene, and surrounding lowlands. Light winds and a strong temperature inversion are trapping pollutants close to the surface. At the same time, a Cold Weather Advisory remains in effect through mid-morning as temperatures plunge into the low 20s.
In Eugene, early readings near 22 degrees make it one of the coldest mornings of the week. Widespread frost coats vehicles and untreated roads. Patchy freezing fog may briefly reduce visibility during the early commute, especially near rivers and open fields. Drivers should watch for slick spots on bridges and shaded streets where flash freezing can occur.
Daytime sunshine helps temperatures recover into the low to mid-40s, but winds stay light. That means air quality improves slowly, if at all. People with asthma, heart disease, or other respiratory conditions may feel symptoms intensify, particularly in the morning and evening. Officials recommend limiting outdoor exertion and avoiding wood burning when possible.
Friday stays dry and cold, with another frosty start and highs in the mid-40s. Clearing skies Friday night allow temperatures to drop again, setting up another cold morning Saturday. By the weekend, better mixing and sunshine should gradually improve air quality, though overnight stagnation may linger in valley pockets.
Looking ahead to early next week, clouds increase and rain chances return, which would help flush trapped pollution. Until then, plan cold-weather layers, drive cautiously during frosty mornings, and check on vulnerable neighbors.
How cold did it feel where you are this morning? Share what you’re seeing across the Willamette Valley.
Five-Day Outlook (Portland–Eugene Area)
Today: Frost early, then partly sunny, highs 43–45.
Friday: Frost and patchy fog early, sunny later, highs near 44.
Saturday: Sunny, high near 45.
Sunday: Partly sunny, highs near 48.
Monday: Mostly cloudy, highs near 49.
