As of 2:43 PM MST on November 4, 2025, all 7 cities in Jefferson County, ID in our database have a UV Index reading of Low. The city with the highest UV Index reading right now is Mud Lake, ID with a reading of 1.7.
Over the next 24 hours, the highest UV Index reading in Jefferson County, ID is expected to be 2.3 in Ririe between 12:00 PM - 1:00 PM MST tomorrow.
| Range | 0 - 2 | 3 - 5 | 6 - 7 | 8 - 10 | 11+ |
|---|---|---|---|---|---|
| Color | |||||
| Risk | Low | Moderate | High | Very High | Extreme |