Hourly Weather | Today Wednesday, May 20, 2026
Boulder, Colorado
4 PM
Rainy Weather
55°
Feels Like 55°
62
Humidity: 66%
UV Index: 2
Wind: 7 mph
5 PM
Cloudy Weather
57°
Feels Like 59°
40
Humidity: 58%
UV Index: 2
Wind: 7 mph
6 PM
Cloudy Weather
55°
Feels Like 55°
34
Humidity: 61%
UV Index: 1
Wind: 7 mph
7 PM
Cloudy Weather
54°
Feels Like 54°
28
Humidity: 67%
UV Index: 1
Wind: 7 mph
8 PM
Cloudy Weather
52°
Feels Like 50°
18
Humidity: 74%
UV Index: 0
Wind: 6 mph
9 PM
Cloudy Night
48°
Feels Like 46°
18
Humidity: 80%
UV Index: 0
Wind: 6 mph
10 PM
Cloudy Night
46°
Feels Like 45°
18
Humidity: 86%
UV Index: 0
Wind: 6 mph
11 PM
Cloudy Night
45°
Feels Like 43°
18
Humidity: 87%
UV Index: 0
Wind: 6 mph

Hourly Air Quality Forecast - AQI (US EPA)

4 PM
41 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.01 µg/m³
  • PM10: 1.55 µg/m³
  • O3: 0.044 ppm
  • NO2: 0.1 ppb
  • SO2: 0 ppb
  • CO: 0.08 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.05 µg/m³
  • PM10: 1.72 µg/m³
  • O3: 0.046 ppm
  • NO2: 0.2 ppb
  • SO2: 0 ppb
  • CO: 0.08 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.04 µg/m³
  • PM10: 1.81 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.2 ppb
  • SO2: 0 ppb
  • CO: 0.08 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.05 µg/m³
  • PM10: 1.81 µg/m³
  • O3: 0.047 ppm
  • NO2: 0.5 ppb
  • SO2: 0 ppb
  • CO: 0.08 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.17 µg/m³
  • PM10: 1.89 µg/m³
  • O3: 0.046 ppm
  • NO2: 1.1 ppb
  • SO2: 0 ppb
  • CO: 0.08 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.28 µg/m³
  • PM10: 1.97 µg/m³
  • O3: 0.045 ppm
  • NO2: 1.4 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
40 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.38 µg/m³
  • PM10: 2.04 µg/m³
  • O3: 0.043 ppm
  • NO2: 1.6 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
39 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.49 µg/m³
  • PM10: 2.14 µg/m³
  • O3: 0.042 ppm
  • NO2: 1.9 ppb
  • SO2: 0 ppb
  • CO: 0.10 ppm

Health Recommendations:

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