Hourly Weather | Today Wednesday, May 20, 2026
Castle Rock, Colorado
5 PM
Cloudy Weather
48°
Feels Like 46°
40
Humidity: 82%
UV Index: 1
Wind: 7 mph
6 PM
Cloudy Weather
48°
Feels Like 46°
34
Humidity: 81%
UV Index: 1
Wind: 7 mph
7 PM
Cloudy Weather
48°
Feels Like 46°
38
Humidity: 84%
UV Index: 0
Wind: 7 mph
8 PM
Rainy Weather
46°
Feels Like 43°
42
Humidity: 85%
UV Index: 0
Wind: 6 mph
9 PM
Cloudy Weather
46°
Feels Like 43°
38
Humidity: 86%
UV Index: 0
Wind: 6 mph
10 PM
Cloudy Night
45°
Feels Like 41°
34
Humidity: 90%
UV Index: 0
Wind: 7 mph
11 PM
Cloudy Night
43°
Feels Like 39°
33
Humidity: 90%
UV Index: 0
Wind: 7 mph

Hourly Air Quality Forecast - AQI (US EPA)

5 PM
42 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.15 µg/m³
  • PM10: 2.7 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.1 ppb
  • SO2: 0.1 ppb
  • CO: 0.08 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

6 PM
43 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.33 µg/m³
  • PM10: 3.25 µg/m³
  • O3: 0.047 ppm
  • NO2: 0.1 ppb
  • SO2: 0.1 ppb
  • CO: 0.08 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

7 PM
40 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.34 µg/m³
  • PM10: 3.02 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.08 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

8 PM
34 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.29 µg/m³
  • PM10: 2.6 µg/m³
  • O3: 0.037 ppm
  • NO2: 0.7 ppb
  • SO2: 0 ppb
  • CO: 0.09 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

9 PM
31 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.27 µg/m³
  • PM10: 2.44 µg/m³
  • O3: 0.033 ppm
  • NO2: 1 ppb
  • SO2: 0 ppb
  • CO: 0.09 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

10 PM
28 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.24 µg/m³
  • PM10: 2.35 µg/m³
  • O3: 0.030 ppm
  • NO2: 1.1 ppb
  • SO2: 0 ppb
  • CO: 0.09 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

11 PM
26 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.23 µg/m³
  • PM10: 2.21 µg/m³
  • O3: 0.029 ppm
  • NO2: 1.2 ppb
  • SO2: 0 ppb
  • CO: 0.09 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.