Is the Air Quality Good in Rosebud, Montana?
Yes — air quality in Rosebud, Montana is good. The city earns an Air Quality Grade of A (excellent) on a 5-year median AQI of 23, which sits in the Good range, and logs only 21 unhealthy-air days over five years (about 4 per year). The general population can breathe outdoors safely on the vast majority of days.
Who Can Safely Breathe the Air in Rosebud, Montana?
For most healthy adults, current air quality in this area does not require any change in behavior. People with severe asthma, COPD, or recent cardiac events should still keep an eye on daily AQI alerts, especially during wildfire season. Because ozone peaks in the afternoon on hot sunny days, plan outdoor exercise for early morning or after sunset on bad-air days.
Across the past five years, this area has logged just 21 days where AQI rose into the "Unhealthy for Sensitive Groups" range or worse — about 4 days per year, or roughly one every other month. That is a low count by national standards.
Rosebud, Montana Air Quality Snapshot
| Air Quality Grade | A87/100 |
| 5-Year Median AQI | 23 (Good) |
| Most Recent Median AQI (2023) | 3 (Good) |
| Dominant Pollutant | Ground-Level Ozone |
| 10-Year Trend | Improving (-3.62 AQI/yr) |
| Unhealthy Days (last 5 yr) | 21 |
| National Rank (cleanest = #1) | #78 of 1,020 (8th cleanest percentile) |
| Montana Rank | #6 of 19 |
What Does the A Grade Mean?
Rosebud, Montana earns an A — it is among the cleanest U.S. cities tracked by EPA monitoring, with median AQI averaging just 23 over the past five years. Days in the "Good" category dominate the calendar; air-quality alerts are rare.
Rosebud, Montana's 5-year median AQI of 23 is 18 points below the national average of 41 — meaningfully cleaner than the typical U.S. metro tracked here. Within Montana, Rosebud, Montana runs cleaner than the state average of 31 — a positive signal that local conditions (terrain, wind patterns, emission sources) are working in residents' favor.
For context within Montana: Ravalli, Montana currently holds the state's cleanest grade (B, AQI 22), while Sanders, Montana sits at the bottom (D, AQI 36).
What's in Rosebud, Montana's Air?
The dominant pollutant in Rosebud, Montana is Ground-Level Ozone. Ground-level ozone forms when sunlight reacts with vehicle exhaust and industrial emissions. It is worst on hot, sunny, stagnant summer days. Ozone irritates the lungs, triggers asthma attacks, and reduces lung function — even healthy adults can feel chest tightness and shortness of breath after exercising in elevated ozone.
Days by Dominant Pollutant (2023)
| Pollutant | Days as Dominant | Share of Year |
|---|---|---|
| Nitrogen Dioxide | 177 | 62% |
| Fine Particulate Matter (PM2.5) | 108 | 38% |
Is the Air Getting Better or Worse?
Air quality in Rosebud, Montana has been improving over the past decade, with median AQI dropping by roughly 3.6 points per year. That is consistent with the broader national pattern — most U.S. metros have seen steady reductions in particulate and ozone pollution since the 2010s as cleaner vehicles and power plants come online.
In 2014, Rosebud, Montana posted a median AQI of 39. By 2023 that figure was 3 — a drop of 36 AQI points cleaner across 10 years of EPA records.
Year-by-Year AQI in Rosebud, Montana
| Year | Median AQI | Good Days | Unhealthy Days | Dominant Pollutant |
|---|---|---|---|---|
| 2014 | 39 | 293 | 3 | Ozone |
| 2015 | 40 | 274 | 9 | Ozone |
| 2016 | 38 | 307 | 1 | Ozone |
| 2017 | 39 | 277 | 11 | Ozone |
| 2018 | 38 | 302 | 2 | Ozone |
| 2019 | 36 | 328 | 1 | Ozone |
| 2020 | 37 | 321 | 5 | Ozone |
| 2021 | 38 | 266 | 14 | Ozone |
| 2022 | 2 | 337 | 0 | NO2 |
| 2023 | 3 | 279 | 1 | NO2 |
How This Grade Is Calculated
The AirHistory Air Quality Grade combines four signals: the 5-year median AQI (40% of the score), the 10-year trend direction (30%), the count of unhealthy days per year (20%), and the dominant pollutant type (10%). All four come directly from the EPA Air Quality System (AQS), which aggregates readings from federally certified monitors. Read the full methodology.
More about Rosebud, Montana
Rosebud, Montana has an Air Quality Grade of A (excellent) with a 5-year median AQI of 23. The dominant pollutant is Ground-Level Ozone, and air quality has been improving over the past decade.
This answer pulls from the EPA Air Quality System (AQS), the authoritative federal source for U.S. air quality and pollution monitoring. The headline number above is the direct answer; what follows is the additional context most readers need to use the answer for a real decision rather than just a fact lookup.
For readers turning this answer into action: cross-reference against the underlying the EPA Air Quality System (AQS) record before acting on time-sensitive decisions. The site renders the data as it was published; subsequent revisions can shift the picture, and the live federal data is always the authoritative current reference.
Source: EPA Outdoor Air Quality Data, 2026.