Hourly Weather | Today Thursday, December 4, 2025
Boulder, Colorado
4 AM
Cloudy Night
16°
Feels Like
0
Humidity: 82%
Wind: 7 mph
UV Index: 0
5 AM
Cloudy Night
16°
Feels Like
0
Humidity: 77%
Wind: 8 mph
UV Index: 0
6 AM
Cloudy Night
16°
Feels Like
0
Humidity: 77%
Wind: 8 mph
UV Index: 0
7 AM
Cloudy Night
19°
Feels Like
0
Humidity: 70%
Wind: 10 mph
UV Index: 0
8 AM
Cloudy Weather
21°
Feels Like 12°
0
Humidity: 64%
Wind: 10 mph
UV Index: 1
9 AM
Cloudy Weather
28°
Feels Like 21°
0
Humidity: 57%
Wind: 9 mph
UV Index: 1
10 AM
Cloudy Weather
34°
Feels Like 34°
0
Humidity: 50%
Wind: 7 mph
UV Index: 2
11 AM
Cloudy Weather
37°
Feels Like 39°
0
Humidity: 47%
Wind: 6 mph
UV Index: 2
12 PM
Cloudy Weather
39°
Feels Like 39°
0
Humidity: 43%
Wind: 8 mph
UV Index: 3
1 PM
Cloudy Weather
43°
Feels Like 37°
0
Humidity: 40%
Wind: 10 mph
UV Index: 2
2 PM
Cloudy Weather
39°
Feels Like 34°
0
Humidity: 41%
Wind: 12 mph
UV Index: 2
3 PM
Cloudy Weather
39°
Feels Like 34°
0
Humidity: 41%
Wind: 10 mph
UV Index: 1
4 PM
Cloudy Weather
36°
Feels Like 30°
0
Humidity: 43%
Wind: 9 mph
UV Index: 1
5 PM
Cloudy Night
34°
Feels Like 27°
0
Humidity: 48%
Wind: 9 mph
UV Index: 0
6 PM
Cloudy Night
32°
Feels Like 25°
0
Humidity: 50%
Wind: 9 mph
UV Index: 0
7 PM
Cloudy Night
32°
Feels Like 25°
0
Humidity: 48%
Wind: 9 mph
UV Index: 0
8 PM
Cloudy Night
30°
Feels Like 23°
0
Humidity: 49%
Wind: 9 mph
UV Index: 0
9 PM
Cloudy Night
30°
Feels Like 21°
0
Humidity: 49%
Wind: 9 mph
UV Index: 0
10 PM
Cloudy Night
30°
Feels Like 21°
0
Humidity: 49%
Wind: 9 mph
UV Index: 0
11 PM
Cloudy Night
30°
Feels Like 21°
0
Humidity: 48%
Wind: 9 mph
UV Index: 0

Hourly Air Quality Forecast - AQI (US EPA)

4 AM
23 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.23 µg/m³
  • PM10: 2.24 µg/m³
  • O3: 0.024 ppm
  • NO2: 2.5 ppb
  • SO2: 0 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

5 AM
22 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.2 µg/m³
  • PM10: 2.2 µg/m³
  • O3: 0.024 ppm
  • NO2: 2.4 ppb
  • SO2: 0 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

6 AM
21 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.2 µg/m³
  • PM10: 2.21 µg/m³
  • O3: 0.023 ppm
  • NO2: 2.3 ppb
  • SO2: 0 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

7 AM
21 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.24 µg/m³
  • PM10: 2.25 µg/m³
  • O3: 0.022 ppm
  • NO2: 2.5 ppb
  • SO2: 0 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

8 AM
21 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.32 µg/m³
  • PM10: 2.35 µg/m³
  • O3: 0.022 ppm
  • NO2: 2.8 ppb
  • SO2: 0 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

9 AM
22 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.29 µg/m³
  • PM10: 2.33 µg/m³
  • O3: 0.023 ppm
  • NO2: 2.4 ppb
  • SO2: 0 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

10 AM
22 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.29 µg/m³
  • PM10: 2.34 µg/m³
  • O3: 0.024 ppm
  • NO2: 1.9 ppb
  • SO2: 0 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

11 AM
23 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.44 µg/m³
  • PM10: 2.49 µg/m³
  • O3: 0.025 ppm
  • NO2: 1.6 ppb
  • SO2: 0 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

12 PM
30 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.94 µg/m³
  • PM10: 1.97 µg/m³
  • O3: 0.032 ppm
  • NO2: 0.9 ppb
  • SO2: 0.1 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

1 PM
32 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.91 µg/m³
  • PM10: 1.94 µg/m³
  • O3: 0.035 ppm
  • NO2: 0.6 ppb
  • SO2: 0.1 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

2 PM
33 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.86 µg/m³
  • PM10: 1.88 µg/m³
  • O3: 0.036 ppm
  • NO2: 0.5 ppb
  • SO2: 0.1 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.59 µg/m³
  • PM10: 1.62 µg/m³
  • O3: 0.037 ppm
  • NO2: 0.4 ppb
  • SO2: 0.1 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.25 µg/m³
  • PM10: 1.28 µg/m³
  • O3: 0.037 ppm
  • NO2: 0.5 ppb
  • SO2: 0.1 ppb
  • CO: 0.08 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.95 µg/m³
  • PM10: 0.98 µg/m³
  • O3: 0.036 ppm
  • NO2: 0.7 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
33 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 0.8 µg/m³
  • PM10: 0.83 µg/m³
  • O3: 0.035 ppm
  • NO2: 0.9 ppb
  • SO2: 0.1 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.75 µg/m³
  • PM10: 0.79 µg/m³
  • O3: 0.034 ppm
  • NO2: 1.1 ppb
  • SO2: 0.1 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.74 µg/m³
  • PM10: 0.78 µg/m³
  • O3: 0.034 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.

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

Pollutant Concentrations:

  • PM2.5: 0.74 µg/m³
  • PM10: 0.79 µg/m³
  • O3: 0.033 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.

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

Pollutant Concentrations:

  • PM2.5: 0.75 µg/m³
  • PM10: 0.8 µg/m³
  • O3: 0.033 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
31 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 0.78 µg/m³
  • PM10: 0.82 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.