Dense fog and stagnant air to clog Tri-Cities area skies for days

Dense fog is forecast in places in the Tri-Cities this week as the National Weather Service issues an air stagnation advisory for most of the Mid-Columbia.

The advisory started at 7 a.m. Tuesday and lifts Thursday morning. However, patches of fog are forecast through Saturday morning, according to the weather service.

The densest fog is forecast for Wednesday morning until 1 p.m.

Drivers who run into dense fog should slow down and use their low-beam headlights, or fog lights it they have them, according to the weather service. High beams may cause glare, making seeing what’s ahead more difficult.

To ensure you are in the proper lane, follow the lines on the road.

In extremely dense fog, turn on your hazard lights and pull into a parking lot, if possible, or as far off the side of the road as possible and turn off all lights except hazard flashing lights, according to the weather service.

Stagnant air this week means pollution may increase and be trapped close to the air, creating issues for those with respiratory problems, according to the weather service.

It recommends no outdoor burning during the advisory and that indoor wood burning be limited.

Cold temperatures are forecast for the Tri-Cities with lows dropping into the high 20s Thursday, Friday and Saturday night. Highs are forecast at 40 to 41 degrees Friday, Saturday and Sunday.

This story was originally published January 12, 2026 at 12:51 PM.