Colorado
Translate
Banner with Colorado and CDPHE logos on left with text on right reading Colorado Air Quality with Department of Public Health and Environment on the next line.

Detailed Air Quality Summary for 08/23/25 (Yesterday)

Learn more about monitoring sites: site descriptions and
real-time monitoring map

All data are collected real-time and have not been corrected nor validated.

Daily Highs:

Area Site Air Quality Max AQI Pollutant Conc. Period Time *
(MST)
Denver METRO
[expand +]		 RFN Moderate 84 Ozone 65 PPB 8-hour 7 PM
Ft. Collins - Greeley
[expand +]		 MFP Moderate 61 Ozone 58 PPB 8-hour 8 PM
Colorado Springs
[expand +]		 ACAD Good 49 Ozone 53 PPB 8-hour 7 PM
Grand Junction
[expand +]		 PAL Good 50 Ozone 54 PPB 8-hour 7 PM
Pueblo
[expand +]		 PWES Moderate 61 Ozone 58 PPB 8-hour 7 PM
Colorado River Valley
[expand +]		 RIFL Moderate 63 Particulate < 2.5 micrometers 15 µg/m3 24-hour 3 AM
Four Corners
[expand +]		 CTZ Good 48 Ozone 52 PPB 8-hour 5 PM
Steamboat Springs
[expand +]		 SSMB Good 26 Particulate < 2.5 micrometers 4 µg/m3 24-hour 9 PM
Aspen
[expand +]		 ASPN Good 42 Ozone 45 PPB 8-hour 7 PM
Other
[expand +]		 LMB Good 46 Particulate < 2.5 micrometers 8 µg/m3 24-hour 3 AM

Area Site Visibility Max VSI 4-hour Average
(1/km)
 Beta Extinction
(1/km)
 Time *
(MST)
Denver DES Poor 105 0.079 0.091 11 AM

* All data are reported in Mountain Standard Time (MST). During daylight savings time add one hour to the reported hour.