As of 5:46 PM MDT on July 18, 2025, all 10 cities in Big Horn County, MT in our database have a UV Index reading of Moderate. The city with the highest UV Index reading right now is Pryor, MT with a reading of 3.3.
Over the next 24 hours, the highest UV Index reading in Big Horn County, MT is expected to be 9.6 in Fort Smith between 1:00 PM - 2:00 PM MDT tomorrow.
| Range | 0 - 2 | 3 - 5 | 6 - 7 | 8 - 10 | 11+ |
|---|---|---|---|---|---|
| Color | |||||
| Risk | Low | Moderate | High | Very High | Extreme |