Williamson County, IL: Current UV Index and Hourly Forecast

As of 6:37 PM CDT on July 21, 2025, all 16 cities in Williamson County, IL in our database have a UV Index reading of Low. The city with the highest UV Index reading right now is Marion, IL with a reading of 1.1.

Over the next 24 hours, the highest UV Index reading in Williamson County, IL is expected to be 10.2 in Creal Springs between 1:00 PM - 2:00 PM CDT tomorrow.

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UV Index Risk Levels
Range0 - 23 - 56 - 78 - 1011+
Color
RiskLowModerateHighVery HighExtreme
UV Index in Williamson County, IL as of 6:37 PM CDT, July 21, 2025

Current UV Index in Cities in Williamson County, IL

6:37 PM CDT, July 21, 2025