MISSOULA — Much of western Montana remains under an air quality advisory as smoke from wildfires spreads across the area.

The Montana Department of Environmental Quality (DEQ) has issued an Air Quality Advisory for Deer Lodge, Granite, Lake, Mineral, Missoula, Powell, Ravalli and Deer Counties through 8 a.m. Tuesday, September 10, 2024.

Frenchtown, Hamilton and Missoula Lake saw “unhealthy” air quality mid-morning Monday morning. The air quality
was “unhealthy for sensitive groups” in the Seeley Lake area.

In Flathead Valley and Thompson Falls, air quality was “moderate,” while in Libby, air quality was “good.”

• If the air quality is unhealthy: State and local health authorities advise people with respiratory or heart conditions, the elderly, and children to avoid prolonged exercise. Everyone else should limit prolonged exercise.
• When air quality is unhealthy for sensitive groups: State and local health authorities advise people with respiratory or heart conditions, the elderly, and children to limit prolonged exertion.
• When the air quality is moderate: State and local health officials advise that people with exceptional sensitivity should limit prolonged or strenuous exercise.

Click here for the latest air quality information from Montana DEQ.

The DEQ uses color-coded classifications for air quality:

• CHESTNUT BROWN: Dangerous – Emergency Health Alert: Everyone is at increased risk of being affected.
• PURPLE: Very unhealthy – health warning – the risk of health effects is increased for everyone.
• RED: Unhealthy – some members of the general population may experience health effects; members of sensitive groups may experience more serious health effects.
• ORANGE: Unhealthy for sensitive groups – members of sensitive groups may experience health effects. The general public is less likely to be affected.
• YELLOW: Moderate – air quality is acceptable. However, there may be a risk for some people, particularly those who are unusually sensitive to air pollution.
• VEGETABLES: Good – air quality is satisfactory and air pollution poses little or no risk.

MTN