Hourly Weather | Today Monday, September 21, 2026
Great Falls, Montana
1 PM
Sunny Weather
73°
Feels Like 77°
0
Humidity: 33%
UV Index: 4
Wind: 8 mph
2 PM
Sunny Weather
75°
Feels Like 79°
0
Humidity: 29%
UV Index: 4
Wind: 8 mph
3 PM
Sunny Weather
79°
Feels Like 81°
0
Humidity: 26%
UV Index: 3
Wind: 8 mph
4 PM
Sunny Weather
81°
Feels Like 81°
0
Humidity: 23%
UV Index: 3
Wind: 8 mph
5 PM
Sunny Weather
79°
Feels Like 79°
0
Humidity: 24%
UV Index: 2
Wind: 8 mph
6 PM
Sunny Weather
75°
Feels Like 73°
0
Humidity: 27%
UV Index: 1
Wind: 8 mph
7 PM
Sunny Weather
72°
Feels Like 70°
0
Humidity: 30%
UV Index: 0
Wind: 8 mph
8 PM
Night
70°
Feels Like 66°
0
Humidity: 34%
UV Index: 0
Wind: 8 mph
9 PM
Night
64°
Feels Like 63°
0
Humidity: 40%
UV Index: 0
Wind: 9 mph
10 PM
Night
63°
Feels Like 59°
0
Humidity: 45%
UV Index: 0
Wind: 9 mph
11 PM
Night
59°
Feels Like 55°
0
Humidity: 50%
UV Index: 0
Wind: 9 mph

Hourly Air Quality Forecast - AQI (US EPA)

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

Pollutant Concentrations:

  • PM2.5: 1.32 µg/m³
  • PM10: 1.96 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.3 ppb
  • SO2: 0 ppb
  • CO: 0.08 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.21 µg/m³
  • PM10: 1.75 µg/m³
  • O3: 0.045 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.

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

Pollutant Concentrations:

  • PM2.5: 1.16 µg/m³
  • PM10: 1.65 µg/m³
  • O3: 0.045 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.

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

Pollutant Concentrations:

  • PM2.5: 1.09 µg/m³
  • PM10: 1.53 µg/m³
  • O3: 0.045 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.

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

Pollutant Concentrations:

  • PM2.5: 1.06 µg/m³
  • PM10: 1.45 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.2 ppb
  • SO2: 0 ppb
  • CO: 0.07 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.04 µg/m³
  • PM10: 1.43 µg/m³
  • O3: 0.044 ppm
  • NO2: 0.4 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
38 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.06 µg/m³
  • PM10: 1.43 µg/m³
  • O3: 0.041 ppm
  • NO2: 0.9 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
34 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.1 µg/m³
  • PM10: 1.47 µg/m³
  • O3: 0.036 ppm
  • NO2: 1.5 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
32 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.13 µg/m³
  • PM10: 1.51 µg/m³
  • O3: 0.034 ppm
  • NO2: 1.8 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: 1.13 µg/m³
  • PM10: 1.51 µg/m³
  • O3: 0.033 ppm
  • NO2: 2 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
30 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.14 µg/m³
  • PM10: 1.53 µg/m³
  • O3: 0.032 ppm
  • NO2: 2.1 ppb
  • SO2: 0 ppb
  • CO: 0.09 ppm

Health Recommendations:

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