As of 7:10 AM CDT on August 8, 2025, all 15 cities in Columbia County, WI in our database have a UV Index reading of Low. The city with the highest UV Index reading right now is Portage, WI with a reading of 0.3.
Over the next 24 hours, the highest UV Index reading in Columbia County, WI is expected to be 7.5 in Lake Wisconsin between 1:00 PM - 2:00 PM CDT today.
| Range | 0 - 2 | 3 - 5 | 6 - 7 | 8 - 10 | 11+ |
|---|---|---|---|---|---|
| Color | |||||
| Risk | Low | Moderate | High | Very High | Extreme |