Regional Tornado Risk
Illinois Tornado Season Guide: Midwest Supercells, Squall Lines, Hail, and Night Storms
A guide to Illinois severe weather, including tornadoes, squall lines, hail, damaging wind, warm fronts, and changing storm modes.
Quick answer: Illinois tornado risk comes from Midwest fronts, warm sectors, squall lines, and supercells that can affect both rural and metro areas.
North-south variety
Northern, central, and southern Illinois can face different storm environments on the same day.
Warm fronts and outflow boundaries can focus local risk.
Metro exposure
Chicago, St. Louis suburbs, and smaller cities need shelter plans for high-occupancy buildings and transit.
A low-probability event can still have high impact.
Warning action
Move to an interior room or basement during tornado warnings.
Do not wait to see a tornado in rain or darkness.