As of 2:10 PM PDT on September 11, 2025, out of 11 cities in Sierra County, CA in our database, 7 cities (64%) have a UV Index reading of Low, while 4 cities (36%) have a UV Index reading of Moderate. The city with the highest UV Index reading right now is Loyalton, CA with a reading of 5.
Over the next 24 hours, the highest UV Index reading in Sierra County, CA is expected to be 6.5 in Loyalton between 1:00 PM - 2:00 PM PDT tomorrow.
| Range | 0 - 2 | 3 - 5 | 6 - 7 | 8 - 10 | 11+ |
|---|---|---|---|---|---|
| Color | |||||
| Risk | Low | Moderate | High | Very High | Extreme |