CHICAGO (WLS) -- You hear us say it all the time: watch those bridges and overpasses for slick spots. But why do bridges and overpasses freeze first?
Most roads lose heat evenly at night. But unlike normal roads - which have ground to help insulate them and keep them warmer - cold air can reach above and below the bridges, cooling the concrete on both sides.
This results in quicker heat loss and a faster freeze than normal roads.