Flathead, Montana Air Quality
Flathead County, Montana (MT)
→ Stableover 10 years
10-Year AQI Trend
The solid line shows the median AQI each year. The dashed line shows the 90th percentile (worst 10% of days).
Air Quality Day Breakdown
Number of days per year in each EPA AQI category. Green = Good (AQI 0-50), Yellow = Moderate (51-100), Orange = Unhealthy for Sensitive Groups (101-150), Red = Unhealthy or worse (151+).
Year-by-Year Data
| Year | Median AQI | 90th Pct | Max AQI | Good Days | Moderate | Unhealthy+ | Pollutant |
|---|---|---|---|---|---|---|---|
| 2023 | 43 | 68 | 160 | 237 | 120 | 8 | PM2.5 |
| 2022 | 41 | 64 | 152 | 249 | 113 | 3 | PM2.5 |
| 2021 | 39 | 66 | 155 | 268 | 88 | 9 | Ozone |
| 2020 | 37 | 59 | 206 | 286 | 72 | 8 | Ozone |
| 2019 | 39 | 61 | 103 | 267 | 97 | 1 | Ozone |
| 2018 | 45 | 70 | 193 | 222 | 127 | 16 | PM2.5 |
| 2017 | 42 | 71 | 275 | 250 | 104 | 11 | PM2.5 |
| 2016 | 37 | 56 | 80 | 298 | 68 | 0 | Ozone |
| 2015 | 44 | 74 | 190 | 216 | 137 | 12 | PM2.5 |
| 2014 | 41 | 64 | 141 | 254 | 109 | 2 | PM2.5 |
What This Means for Flathead County Residents
Flathead, Montana has received an Air Quality Grade of C (63/100) based on a decade of monitoring data from the EPA's air quality monitoring program. The current median AQI of 43 falls in the "Good" range.
The primary pollutant affecting this area is Fine Particulate Matter (PM2.5). Over the past 5 years, this area has averaged 6 unhealthy air quality days per year — days when sensitive groups (children, elderly, those with respiratory conditions) should limit outdoor activity. The American Lung Association's State of the Air report provides additional context on long-term health risks from air pollution exposure.
Related Cities in Montana
Frequently Asked Questions
Flathead, Montana has a current median AQI of 43, which falls in the "Good" range. The area has received an Air Quality Grade of C (63/100) based on 10 years of EPA monitoring data.
Air quality in Flathead, Montana is stable over the past decade. The median AQI has changed by +2 points from 2014 to 2023.
Flathead, Montana averages 6 unhealthy air quality days per year over the past 5 years. On these days, sensitive groups including children, the elderly, and those with respiratory conditions should limit outdoor activity.
The primary pollutant affecting Flathead, Montana is Fine Particulate Matter (PM2.5). This is the dominant contributor to elevated AQI readings in the Flathead County area.
Flathead, Montana averages 6 unhealthy air days per year. Asthma patients should monitor daily AQI readings and limit outdoor activity when AQI exceeds 100. The primary pollutant is Fine Particulate Matter (PM2.5), which is a known asthma trigger.
With a median AQI of 43 (Good), outdoor exercise in Flathead, Montana is generally safe year-round. Flathead, Montana averages 6 days per year when athletes should move workouts indoors.