Granite County Public Health

09/02/2026

POST: Scarecrow Days

08/20/2026

08/19/2026

08/13/2026

Understanding the Montana Air Quality Index (AQI)

With fire season upon us in Montana, the Jefferson County Health Department thought it would be a good opportunity to discuss wildfire smoke (PM2.5), who it affects, and what smoke conditions may look like for those who don't have a way to check official air quality readings.
Wildfire smoke can change our air quality quickly. Understanding the Air Quality Index (AQI) can help you make informed decisions to protect your health.

🟢 AQI 0–50 | Good
Air quality is healthy for everyone. Enjoy your normal outdoor activities.
Visual observations:
• Clear skies with visibility of 10+ miles.
• Mountains and distant ridgelines are clearly visible.

🟡 AQI 51–100 | Moderate
Air quality is acceptable for most people. Individuals who are unusually sensitive to smoke or air pollution should consider reducing prolonged or strenuous outdoor activity.
Visual observations:
• Light haze with visibility of 5–10 miles.
• Distant objects are still easy to see.

🟠 AQI 101–150 | Unhealthy for Sensitive Groups
Children, older adults, pregnant people, and those with asthma, COPD, heart disease, or other lung conditions should limit prolonged or strenuous outdoor activity. Others can usually continue normal activities.
Visual observations:
• Hazy skies with visibility of 3–5 miles.
• Distant hills or mountains may appear faded or blurry.

🔴 AQI 151–200 | Unhealthy
Everyone should reduce prolonged or strenuous outdoor activity. Sensitive groups should stay indoors as much as possible in cleaner air.
Visual observations:
• Smoky air with visibility of 1–3 miles.
• Thick haze; mountains may be difficult to see or partially obscured.

🟣 AQI 201–300 | Very Unhealthy
Health alert! Everyone should avoid prolonged outdoor exposure and move activities indoors when possible.
Visual observations:
• Thick smoke with visibility of ½–1 mile.
• The landscape appears washed out or gray.

🟤 AQI 301+ | Hazardous
Emergency conditions. Stay indoors with clean air if possible and follow guidance from local officials.
Visual observations:
• Dense smoke with visibility of less than ½ mile.
• Nearby objects may appear dim or disappear quickly in the haze.

Remember: Smoke conditions can change throughout the day. Before heading outside, check the latest Montana DEQ air quality conditions and plan your activities accordingly.

https://gis.mtdeq.us/portal/apps/experiencebuilder/experience/?id=000f42b119c44c7f9c3b4336470c721e

AirNow Fire and Smoke Map: https://fire.airnow.gov/ #8.56/46.2633/-112.2984

Stay informed. Stay prepared. Protect your lungs.

Visual observations are approximate and should not replace official AQI readings.

08/12/2026

By Thursday afternoon, the Rapid Refresh Forecast System (RRFS) smoke model shows less surface smoke over the state thanks to clouds, cooler air, and much-needed precipitation.

Source: HRRR-smoke

Montana Department of Environmental Quality has issued an air quality alert for Beaverhead, Deer Lodge, Granite, Madison, Missoula, Ravalli, Silver Bow counties in effect until 9AM on 08/13/2026.

Air Quality Alerts continue for several western Montana counties through Thursday morning. Clouds, cooler air, and beneficial rain should ease fire behavior and reduce smoke production late Wednesday through Friday.

Conditions can change quickly as weather could stimulate active fires and the likelihood of new starts increases. Please keep track of concentrations at todaysair.mtdeq.us or the Fire and Smoke Map.

08/12/2026

With the current air quality index floating between “moderate” and “unhealthy” and occasionally “very unhealthy,” it’s important to think about the indoor air quality at home.

Here is a simple method to create a home air cleaning system with supplies you may have on hand or can find in our local hardware stores. We also have some supplies on hand at the Public Health Office and can help assemble these.

Please contact us if you are in need of supplies or assistance with creating your own air cleaning system!

08/10/2026

Wildfire season is here. Wildfire smoke can affect both outdoor and indoor air quality, impacting the health of everyone—especially children, older adults, pregnant women, and people with heart or lung conditions. https://dphhs.mt.gov/airquality/SmokefromFires