April Was Colder And Wetter Than Average In Illinois.

(Undated) -- April weather in Illinois was a little cooler and wetter than normal. Average statewide precipitation last month came in at 5.11-inches says state climatologist Jim Angel. With a statewide average temperature of just under 52-degrees, April in Illinois was slightly cooler than average and marks the sixth month in a row we've seen lower temps than normal.