As of 7:10 AM MDT on August 30, 2025, all 18 cities in Gallatin County, MT in our database have a UV Index reading of 0, indicating no radiation from the sun.
Over the next 24 hours, the highest UV Index reading in Gallatin County, MT is expected to be 7.8 in Big Sky between 1:00 PM - 2:00 PM MDT today.
| Range | 0 - 2 | 3 - 5 | 6 - 7 | 8 - 10 | 11+ |
|---|---|---|---|---|---|
| Color | |||||
| Risk | Low | Moderate | High | Very High | Extreme |