I have icicles hanging from the bottom of the rear bumper of my v6 2021 Camaro when the temperature is below freezing. What could be causing this problem?

 

You live in a cold climate where water on your car freezes??

 

I live in Iowa and it does get down to z ero now and then but the Camaro is in a garage but when I drive it and the temperature is below freezing icicles form across the bottom of the rear bumper @ a foot each direction from center.

 

Icicles do not form anywhere else on the body or undercarriage of the car, just the bottom of the rear bumper.