Smoke is clogging the skies over western Montana, causing air quality monitors to drop Missoula's air quality rating to "Unhealthy," today August 20.

According to Sarah Cofield from the Missoula City-County Health Department the air is the worst it has been for many years, but the real hazard could be duration.

"It's certainly the worst it has been in Missoula for the past few years," Cofield. "2012 was a really rough year, it was particularly difficult because the smoke hit us right before school started and stuck around till October. This is not the worst I've seen, but it has the potential to stick around with us for a very long time."

In many ways, Missoula is better off than other areas. Hamilton, Kalispell and Libby are all facing a "Very Unhealthy" warning. The smoke is pouring in from fires in Idaho and Washington, brought by westerly winds that are expected to keep blowing for days.

Below is the Missoula air quality report for "Unhealthy."

Photo courtesy of NBC Montana