Here comes the smog.
Many of northern Utah's urban valleys, capped by pollution-trapping air inversions due to a continuing high pressure front aloft, were graded "orange," or with seriously compromised, unhealthy air quality heading toward the weekend.
The Utah Division of Air Quality does not expect the pollution in the Wasatch Front's metro areas to improve anytime soon, either, with the next storm system not expected until the middle of next week, at the earliest.
In Salt Lake, Davis, Weber, Cache, Box Elder and Utah counties, mandatory restrictions on solid-fuel burning devices, open burning and unnecessary driving were in place for Friday. Further, health professionals urged those with compromised heart and lung function, the elderly and very young to avoid outdoor activity.