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AirHistory

Air Quality in Colorado

10-year air quality trends for 32 monitored areas in Colorado.

See full Colorado air quality rankings →
32
Cities
39
Avg AQI (5yr)
3
Improving
6
Stable
23
Worsening

All Monitored Areas in Colorado

Alamosa, Colorado

Alamosa County · AQI 14 (5yr avg) · Improving · PM10

A

Fremont, Colorado

Fremont County · AQI 13 (5yr avg) · Stable · PM10

A

Routt, Colorado

Routt County · AQI 14 (5yr avg) · Stable · PM10

A

Pitkin, Colorado

Pitkin County · AQI 13 (5yr avg) · Stable · PM10

B

San Juan, Colorado

San Juan County · AQI 9 (5yr avg) · Stable · PM2.5

B

Prowers, Colorado

Prowers County · AQI 17 (5yr avg) · Stable · PM10

B

Jackson, Colorado

Jackson County · AQI 21 (5yr avg) · Worsening · PM2.5

B

Pueblo, Colorado

Pueblo County · AQI 27 (5yr avg) · Worsening · PM2.5

B

Mesa, Colorado

Mesa County · AQI 45 (5yr avg) · Improving · Ozone

B

Montezuma, Colorado

Montezuma County · AQI 44 (5yr avg) · Stable · Ozone

C

Gunnison, Colorado

Gunnison County · AQI 46 (5yr avg) · Stable · Ozone

C

La Plata, Colorado

La Plata County · AQI 46 (5yr avg) · Stable · Ozone

C

Moffat, Colorado

Moffat County · AQI 42 (5yr avg) · Worsening · Ozone

C

Rio Blanco, Colorado

Rio Blanco County · AQI 47 (5yr avg) · Stable · Ozone

C

San Miguel, Colorado

San Miguel County · AQI 47 (5yr avg) · Worsening · Ozone

C

Grand, Colorado

Grand County · AQI 46 (5yr avg) · Worsening · Ozone

C

El Paso, Colorado

El Paso County · AQI 46 (5yr avg) · Stable · Ozone

C

Clear Creek, Colorado

Clear Creek County · AQI 48 (5yr avg) · Stable · Ozone

C

Gilpin, Colorado

Gilpin County · AQI 46 (5yr avg) · Worsening · Ozone

C

Park, Colorado

Park County · AQI 49 (5yr avg) · Worsening · Ozone

C

Arapahoe, Colorado

Arapahoe County · AQI 46 (5yr avg) · Stable · Ozone

C

Garfield, Colorado

Garfield County · AQI 50 (5yr avg) · Worsening · Ozone

C

Adams, Colorado

Adams County · AQI 50 (5yr avg) · Worsening · Ozone

C

Denver, Colorado

Denver County · AQI 54 (5yr avg) · Stable · PM2.5

C

Archuleta, Colorado

Archuleta County · AQI 39 (5yr avg) · Worsening · Ozone

C

Larimer, Colorado

Larimer County · AQI 51 (5yr avg) · Stable · Ozone

C

Chaffee, Colorado

Chaffee County · AQI 53 (5yr avg) · Worsening · Ozone

C

Delta, Colorado

Delta County · AQI 42 (5yr avg) · Worsening · Ozone

C

Douglas, Colorado

Douglas County · AQI 47 (5yr avg) · Worsening · Ozone

D

Boulder, Colorado

Boulder County · AQI 50 (5yr avg) · Worsening · Ozone

D

Weld, Colorado

Weld County · AQI 53 (5yr avg) · Worsening · Ozone

D

Jefferson, Colorado

Jefferson County · AQI 47 (5yr avg) · Stable · Ozone

D
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Frequently Asked Questions

Colorado has 32 monitored areas with an average 5-year AQI of 39 and an average Air Quality Grade of B. 3 cities are improving, 23 are worsening, and 6 are stable.

Alamosa, Colorado has the best Air Quality Grade (A) in Colorado with a 5-year average AQI of 14.

Of 32 monitored areas in Colorado, 3 are showing improving trends, 23 are worsening, and 6 remain stable over the past decade.

Sources: EPA Air Quality System (AQS)
Last updated: