As of 2:28 PM MDT on September 12, 2026, out of 18 cities in Gallatin County, MT in our database, 16 cities (89%) have a UV Index reading of Moderate, while 2 cities (11%) have a UV Index reading of High. The city with the highest UV Index reading right now is Hebgen Lake Estates, MT with a reading of 5.8.
Over the next 24 hours, the highest UV Index reading in Gallatin County, MT is expected to be 6.5 in West Yellowstone 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 |