Finally, some good news on Tri-Cities air quality. How long will it last?

The Tri-Cities saw some much-welcomed relief from smoky air on Tuesday.

The air quality was rated as “unhealthy for sensitive groups” by the Washington state Department of Ecology.

It was a major improvement since Sunday when air was rated as “hazardous,” the worst in recent years.

Wind from the northeast helped thin the smoke Monday and Tuesday, just in time for the opening of the Benton Franklin Fair and Rodeo on Tuesday.

Further clearing of smoke is expected Thursday as another weather system moves across the Tri-City area with winds from the west.

Much of the smoke that has choked the Tri-Cities recently is from fires burning to the north in British Columbia, Canada, and northern Washington state.

An air quality alert remains in effect for the Tri-Cities, along with most of Eastern Washington, until noon Thursday.

Western Washington is under an air quality alert until 5 p.m. Wednesday.

There were reports of falling ash in the the Seattle area, as the northeasterly winds helped clear Eastern Washington but moved smoke into Western Washington.

With Tri-City air rated as “unhealthy for sensitive groups,” certain people should limit time outdoors, according to the Department of Ecology.

They include infants, children, pregnant women and older adults. They also include people with health conditions like asthma, diabetes, other heart and lung disease, and stroke survivors.

The air quality rating for smoke in the Tri-Cities is based on monitoring results from air near North Kellogg Street and West Metaline Avenue.

However, it can vary around the Tri-Cities.

The Washington Smoke Information blog says you should use visibility to see how much smoke is in your area.

If visibility is about five miles, sensitive groups should minimize outdoor activity. At three miles, everyone should minimize outdoor activity.

At one mile, everyone should stay indoors.

The change in the weather Thursday also should bring cooler temperatures.

The blanket of smoke over the Mid-Columbia has cooled temperatures by 5 to 10 degrees already, according to the weather service.

Highs Wednesday and Thursday should be in the high 80s to low 90s in the Tri-Cities.

But highs should drop to the low 80s Friday through Monday, according to the early forecast.

This story was originally published August 21, 2018 at 12:34 PM.