As of 5:00 AM CDT on August 31, 2025, all 7 cities in Union County, SD in our database have a UV Index reading of 0, indicating no radiation from the sun.
Over the next 24 hours, the highest UV Index reading in Union County, SD is expected to be 3.2 in Dakota Dunes between 3:00 PM - 4:00 PM CDT today.
| Range | 0 - 2 | 3 - 5 | 6 - 7 | 8 - 10 | 11+ |
|---|---|---|---|---|---|
| Color | |||||
| Risk | Low | Moderate | High | Very High | Extreme |