Pendleton, Oregon — Freezing fog and stagnant air conditions are affecting parts of southeast Washington early Thursday, creating hazardous driving conditions and degraded air quality.
According to the National Weather Service in Pendleton, a Freezing Fog Advisory is in effect until noon PST today for the foothills of the Blue Mountains of Washington, including Walla Walla, Dayton, and Waitsburg. Visibility may drop to one-quarter mile or less, increasing the risk of accidents during the morning commute. Some road surfaces may also become slick where fog freezes.
In addition, an Air Stagnation Advisory remains in effect until 10 a.m. PST Friday. Forecasters said a persistent temperature inversion and light winds are trapping pollutants near the ground, leading to poor air quality, especially in valley locations.
The National Weather Service warned that low visibility could make driving hazardous, particularly during early morning travel. Drivers are urged to slow down, use headlights, and increase following distance. Sudden changes in visibility are possible along roadways.
Air quality officials advise people with respiratory conditions, older adults, and children to limit prolonged outdoor activity. State agencies also recommend limiting outdoor and residential wood burning during the advisory period.
Conditions are expected to gradually improve later today as fog lifts, though air quality issues may persist into Friday morning until stronger weather systems break up the stagnant air.
