A winter temperature inversion traps smog over the Salt Lake Valley. A new University of Utah study found that as much as 13 percent of the water vapor in the smog comes from fossil-fuel combustion.

There’s a particularly mucky inversion plaguing Salt Lake City this week, and it may not clear out until at least Saturday, when a weather system is expected to move in and break up the smog. Salt ...

5pm: Explaining why 4 Utah cities made Top 10 worst US air quality list SALT LAKE CITY — Utah continues to have some of the worst air quality in the U.S. amid the latest temperature inversion ...

The stagnant air sitting across Salt Lake County last weekend seemed to grow unusually dense to the untrained eye, even for an inversion. Yet, according to a meteorologist who works in the National ...