As of 1:05 PM CDT on July 21, 2025, out of 1461 cities in Illinois in our database, 773 cities (53%) have a UV Index reading of Very High, 466 cities (32%) have a UV Index reading of High, 188 cities (13%) have a UV Index reading of Moderate, 32 cities (2%) have a UV Index reading of Extreme, while 2 cities (0%) have a UV Index reading of Low. The city with the highest UV Index reading right now is Rockwood, IL with a reading of 10.6.
Over the next 24 hours, the highest UV Index reading in Illinois is expected to be 10.6 in Rockwood 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 |