UV Index Today in St. Charles County, Missouri (MO)

The average maximum UV Index today across 35 locations in St. Charles County, Missouri (MO), is 4.9. The highest projected maximum is 5.7 in Washington at 1:00 PM CDT, while the lowest projected maximum is 4.4 in Alton at 1:00 PM CDT.

Tomorrow, the average maximum UV Index across those same locations is expected to be 5.6. The highest projected maximum is 5.7 in O'Fallon at 1:00 PM CDT, and the lowest projected maximum is 5.5 in Florissant at 1:00 PM CDT.