We bring you warnings about air quality in Montana from the Department of Environmental Quality's air monitors, which are set up in various locations. The gauges measure the concentration of particles in the air, in this case, wildfire smoke. From that smoke concentration, the air quality can go from "Good" to "Moderate" to "Unhealthy for Sensitive Groups" to "Unhealthy" and then "Very Unhealthy," topped off with "Hazardous." On the Montana Today's Air website, select the date and you can see specifics on which concentrations cause which air quality listing.
Wondering if you fit in the Sensitive Group? Here are the details: