Air quality across many parts of Montana is currently rated at levels ranging from "unhealthy for sensitive groups" to "very unhealthy."
The cause of the poor air quality is smoke pouring in to Montana from wildfires in several western states, including Oregon and California.
As of 10 a.m. on Monday, the Montana Department of Environmental Quality reports that the following areas have air quality that is unhealthy: Great Falls, Helena, Lewistown, Hamilton, West Yellowstone, Bozeman, Butte, Missoula, and the Flathead Valley.
Air quality in the Libby and Thompson Falls region in northwestern Montana is listed as very unhealthy.
Areas along most areas of the Hi-Line east of the Divide remain largely unaffected, with air quality listed as good. The exception is Cut Bank, which is listed as moderate.
Here is an explanation from MT DEQ about the different categories:
- HAZARDOUS: All children and adults should avoid or limit all outdoor exertion
- VERY UNHEALTHY: Active children and adults, and people with respiratory disease, such as asthma, should avoid all outdoor exertion; everyone else, especially children, should limit outdoor exertion
- UNHEALTHY: Active children and adults, and people with respiratory disease, such as asthma, should avoid prolonged outdoor exertion; everyone else, especially children, should limit prolonged outdoor exertion
- UNHEALTHY FOR SENSITIVE GROUPS: Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion
- MODERATE: Unusually sensitive people should consider limiting prolonged outdoor exertion
From the MT DEQ website on Monday morning:
Smoke has been moving into Montana from wildfires in Idaho, Washington, and Oregon. Air quality has reached HAZARDOUS in Libby, VERY UNHEALTHY in Thompson Falls, and UNHEALTHY in the Flathead Valley. Seeley Lake and Hamilton have both reported air quality levels at UNHEALTHY FOR SENSITIVE GROUPS. Other sites around the state are reporting GOOD or MODERATE air quality, but may worsen as the day continues.