As of 3:40 PM CDT on July 29, 2025, all 119 cities in Cook County, IL in our database have a UV Index reading of High. The city with the highest UV Index reading right now is Hoffman Estates, IL with a reading of 6.5.
Over the next 24 hours, the highest UV Index reading in Cook County, IL is expected to be 8 in Orland Park between 1:00 PM - 2:00 PM CDT tomorrow.
| Range | 0 - 2 | 3 - 5 | 6 - 7 | 8 - 10 | 11+ |
|---|---|---|---|---|---|
| Color | |||||
| Risk | Low | Moderate | High | Very High | Extreme |