As of 4:44 PM MST on January 27, 2026, 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 Roberts, ID with a reading of 0.4.
Over the next 24 hours, the highest UV Index reading in Jefferson County, ID is expected to be 1.4 in Ririe between 1:00 PM - 2:00 PM MST tomorrow.
| Range | 0 - 2 | 3 - 5 | 6 - 7 | 8 - 10 | 11+ |
|---|---|---|---|---|---|
| Color | |||||
| Risk | Low | Moderate | High | Very High | Extreme |