Air quality in Helena
The US Air Quality Index (EPA) grades air from 0 to 500 using fine particles (PM2.5/PM10), ozone and nitrogen dioxide. 0-50 is Good, 51-100 Moderate, 101-150 Unhealthy for Sensitive Groups, and anything higher affects everyone.
PM2.5
4.2 µg/m³
WHO guideline 15
PM10
5.1 µg/m³
WHO guideline 45
Hour by hour (12h)
US EPA AQI
5:00 PM
💨
PM2.5 4.2 µg/m³
46Good
6:00 PM
💨
PM2.5 4.2 µg/m³
44Good
7:00 PM
💨
PM2.5 4.3 µg/m³
42Good
8:00 PM
💨
PM2.5 4.8 µg/m³
38Good
9:00 PM
💨
PM2.5 5.3 µg/m³
33Good
10:00 PM
💨
PM2.5 5.7 µg/m³
29Good
11:00 PM
💨
PM2.5 6.1 µg/m³
27Good
12:00 AM
💨
PM2.5 6.5 µg/m³
27Good
1:00 AM
💨
PM2.5 7 µg/m³
29Good
2:00 AM
💨
PM2.5 7.5 µg/m³
31Good
3:00 AM
💨
PM2.5 8.1 µg/m³
34Good
4:00 AM
💨
PM2.5 8.9 µg/m³
37Good
Next few days
daily max · US EPA AQI
Wed
💨
Good · UV Very high
48
Thu
💨
Moderate · UV Very high
60
Fri
💨
Unhealthy for Sensitive Groups · UV Very high
108
Sat
💨
Good · UV Very high
48
Sun
💨
Good · UV Very high
24