Alamosa, Colorado Air Quality
Alamosa air quality today — the AQI, the main pollutant, and whether it’s safe to exercise outside right now
Alamosa, CO · Air quality right now
The air quality index in Alamosa, CO is 36 (Good) right now — safe for outdoor activity.
Is it safe to be outside in Alamosa today?
AQI 36 Yes — air quality is Good
Air is clean — great for outdoor activity.Main pollutant: OzoneObserved 1:00 AM MDT
Pollutants right now
- PM2.51.8 µg/m³fine particles — smoke, exhaust, soot
- PM101.9 µg/m³coarse particles — dust, pollen, ash
- Ozone44 µg/m³Main pollutantsmog — builds on hot, sunny days
- NO₂7.2 µg/m³nitrogen dioxide — traffic, combustion
ExerciseOK to run — no air-quality limits on outdoor exercise.
How to read Alamosa’s air quality
Guides: The AQI Scale, Explained · Air Quality Alerts, Decoded · How to Read a Wildfire Smoke Map · Why Wildfire Smoke Travels 1,000 Miles.
Air quality over time in Alamosa
Across the EPA’s county records from 2020 to 2025, Alamosa’s cleanest year was 2022 (median AQI 11) and its most polluted was 2024 (median AQI 26); the typical (median) day has trended more polluted since 2020.
| Year | Median AQI | Unhealthy+ | Main pollutant | USG | Moderate | Good |
|---|---|---|---|---|---|---|
| 2020 | 14 | 0 | PM2.5 | 0 | 7 | 112 |
| 2021 | 12 | 0 | PM2.5 | 1 | 5 | 114 |
| 2022 | 11 | 0 | PM2.5 | 1 | 8 | 107 |
| 2023 | 22 | 0 | PM2.5 | 0 | 23 | 142 |
| 2024 | 26 | 0 | PM2.5 | 0 | 40 | 325 |
| 2025 | 25 | 0 | PM2.5 | 0 | 31 | 334 |
“USG” is Unhealthy for Sensitive Groups (AQI 101–150); “Unhealthy+” combines the Unhealthy, Very Unhealthy, and Hazardous days. In 2024 the EPA tightened the annual fine-particle (PM2.5) standard to 9 µg/m³ from the previous 12 µg/m³, so counties near the old limit read worse against the new one. Source: EPA AQS annual summaries, 2020–2025.
Frequently asked
- What was the worst year for air quality in Alamosa?
- In the EPA's 2020–2025 county records, 2021 had the most days above AQI 100: 1 day (1 Unhealthy for Sensitive Groups, 0 Unhealthy or worse). The highest median AQI came in 2024 (26; 2021's was 12).
- How many unhealthy air days does Alamosa have?
- Across 2020–2025, under 1% of the days reported for Alamosa's county had an AQI above 100 (2 of 1250), fewer than one a year on average. 2025 had 0 days.
- What's the main air pollutant in Alamosa?
- PM2.5: it drove Alamosa's county AQI on the most days in every year of the EPA's 2020–2025 records.