Hourly Weather | Today Wednesday, March 18, 2026
Helena, Montana
3 AM
Rainy Weather
43°
Feels Like 39°
49
Humidity: 60%
UV Index: 0
Wind: 6 mph
4 AM
Night
43°
Feels Like 39°
44
Humidity: 64%
UV Index: 0
Wind: 6 mph
5 AM
Cloudy Night
41°
Feels Like 39°
17
Humidity: 66%
UV Index: 0
Wind: 6 mph
6 AM
Cloudy Night
39°
Feels Like 37°
17
Humidity: 67%
UV Index: 0
Wind: 6 mph
7 AM
Cloudy Night
37°
Feels Like 36°
11
Humidity: 71%
UV Index: 0
Wind: 6 mph
8 AM
Cloudy Weather
39°
Feels Like 36°
0
Humidity: 67%
UV Index: 1
Wind: 8 mph
9 AM
Cloudy Weather
43°
Feels Like 41°
0
Humidity: 63%
UV Index: 2
Wind: 8 mph
10 AM
Cloudy Weather
46°
Feels Like 43°
0
Humidity: 58%
UV Index: 3
Wind: 11 mph
11 AM
Cloudy Weather
50°
Feels Like 48°
0
Humidity: 48%
UV Index: 3
Wind: 12 mph
12 PM
Cloudy Weather
55°
Feels Like 52°
0
Humidity: 40%
UV Index: 4
Wind: 16 mph
1 PM
Cloudy Weather
59°
Feels Like 55°
0
Humidity: 34%
UV Index: 3
Wind: 17 mph
2 PM
Cloudy Weather
63°
Feels Like 61°
0
Humidity: 29%
UV Index: 3
Wind: 16 mph
3 PM
Cloudy Weather
64°
Feels Like 63°
0
Humidity: 26%
UV Index: 2
Wind: 16 mph
4 PM
Cloudy Weather
68°
Feels Like 66°
0
Humidity: 23%
UV Index: 2
Wind: 16 mph
5 PM
Cloudy Weather
66°
Feels Like 63°
0
Humidity: 25%
UV Index: 1
Wind: 14 mph
6 PM
Cloudy Weather
63°
Feels Like 59°
0
Humidity: 27%
UV Index: 1
Wind: 12 mph
7 PM
Cloudy Weather
61°
Feels Like 57°
0
Humidity: 29%
UV Index: 0
Wind: 11 mph
8 PM
Cloudy Weather
57°
Feels Like 55°
0
Humidity: 32%
UV Index: 0
Wind: 8 mph
9 PM
Cloudy Weather
55°
Feels Like 52°
0
Humidity: 36%
UV Index: 0
Wind: 7 mph
10 PM
Cloudy Night
52°
Feels Like 50°
0
Humidity: 40%
UV Index: 0
Wind: 7 mph
11 PM
Cloudy Night
50°
Feels Like 46°
0
Humidity: 45%
UV Index: 0
Wind: 6 mph

Hourly Air Quality Forecast - AQI (US EPA)

3 AM
26 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 0.6 µg/m³
  • PM10: 0.68 µg/m³
  • O3: 0.028 ppm
  • NO2: 1.2 ppb
  • SO2: 0 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.62 µg/m³
  • PM10: 0.7 µg/m³
  • O3: 0.027 ppm
  • NO2: 1.1 ppb
  • SO2: 0 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.64 µg/m³
  • PM10: 0.73 µg/m³
  • O3: 0.026 ppm
  • NO2: 1 ppb
  • SO2: 0 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.66 µg/m³
  • PM10: 0.76 µg/m³
  • O3: 0.026 ppm
  • NO2: 1 ppb
  • SO2: 0 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.67 µg/m³
  • PM10: 0.76 µg/m³
  • O3: 0.025 ppm
  • NO2: 1 ppb
  • SO2: 0 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.67 µg/m³
  • PM10: 0.76 µg/m³
  • O3: 0.024 ppm
  • NO2: 1.2 ppb
  • SO2: 0 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.69 µg/m³
  • PM10: 0.78 µg/m³
  • O3: 0.025 ppm
  • NO2: 1.5 ppb
  • SO2: 0 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.7 µg/m³
  • PM10: 0.79 µg/m³
  • O3: 0.026 ppm
  • NO2: 1.3 ppb
  • SO2: 0 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.7 µg/m³
  • PM10: 0.79 µg/m³
  • O3: 0.028 ppm
  • NO2: 1.1 ppb
  • SO2: 0 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.73 µg/m³
  • PM10: 0.81 µg/m³
  • O3: 0.031 ppm
  • NO2: 0.9 ppb
  • SO2: 0 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.59 µg/m³
  • O3: 0.043 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.

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.56 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.

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.57 µg/m³
  • O3: 0.043 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.

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.59 µg/m³
  • O3: 0.043 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
40 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 0.51 µg/m³
  • PM10: 0.63 µg/m³
  • O3: 0.043 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.

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

Pollutant Concentrations:

  • PM2.5: 0.53 µg/m³
  • PM10: 0.69 µg/m³
  • O3: 0.042 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.

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

Pollutant Concentrations:

  • PM2.5: 0.59 µg/m³
  • PM10: 0.75 µg/m³
  • O3: 0.039 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
33 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 0.67 µg/m³
  • PM10: 0.85 µg/m³
  • O3: 0.035 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
30 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 0.75 µg/m³
  • PM10: 0.94 µg/m³
  • O3: 0.033 ppm
  • NO2: 1.3 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: 0.78 µg/m³
  • PM10: 0.99 µg/m³
  • O3: 0.030 ppm
  • NO2: 1.3 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
27 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 0.82 µg/m³
  • PM10: 1.05 µg/m³
  • O3: 0.029 ppm
  • NO2: 1.3 ppb
  • SO2: 0 ppb
  • CO: 0.10 ppm

Health Recommendations:

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