Which catastrophic peril is generally considered the primary natural-catastrophe exposure for Illinois homeowners?

Why this is the answer

Illinois sits in a transition zone between Tornado Alley and Dixie Alley, with frequent severe convective storms producing tornadoes, damaging straight-line winds, and large hail. Hurricane storm surge does not reach Illinois, and wildfire exposure is limited. Insurers commonly apply percentage wind/hail deductibles in tornado-prone counties; the FAIR Plan provides basic wind/hail coverage when the voluntary market declines.