SALT LAKE CITY (AP) — Pollution is building up along the Wasatch Front, home of 2 million Utah residents.
The Utah Division of Air Quality issued a health alert for Salt Lake, Davis, Weber, Cache and Utah counties.
It's the second day of bad air for northern Utah's urban corridor, and the National Weather Service says stagnant conditions will run through Friday.
Officials issue alerts when atmospheric inversions trap cold air and pollutants in bowl-shaped mountain valleys.
Authorities are prohibiting wood burning along the Wasatch Front and urging people to limit driving.