The highest AQ index in Montana (as of 14:00 MDT) is currently the Great Falls area. Particle Pollution (PM2.5) is measuring at 132 (Unhealthy for Sensitive Groups). This means members of sensitive groups may experience health effects. The general public is less likely to be affected.
| Range | 0 - 50 | 51 - 100 | 101 - 150 | 151 - 200 | 201 - 300 | 301 - 500 |
| Color | ||||||
| Category | Good | Moderate | Unhealthy for Sensitive Groups | Unhealthy | Very Unhealthy | Hazardous |
Last Updated 10 minutes ago
Below is a list of counties in Montana. Click on any county below and you'll get a list of cities where we provide AQ index forecasts.