On Thursday at 9:53 a.m. an air stagnation advisory was released by the National Weather Service in effect until Friday at noon for North Oregon Coast Range Lowlands, Central Oregon Coast Range Lowlands, Lower Columbia River, Tualatin Valley, West Central Willamette Valley, East Central Willamette Valley, Benton County Lowlands, Linn County Lowlands, Lane County Lowlands and Clackamas County Cascade Foothills.

"Light winds and limited air movement will lead to a period of stagnant air conditions," can be anticipated according to the weather service. "Temperatures have generally warmed above 25 degrees at this time. Therefore, will let the Cold Weather Advisory expire."

News Source : https://www.oregonlive.com/weather-alerts/2026/01/air-stagnation-advisory-for-oregon-until-friday-midday.html