12 degrees out right now. Didn't add enough antifreeze, and upper radiator hose froze, as did part of radiator. Got the upper hose thawed, hopefully radiator will thaw with next drive. Been adding antifreeze as it will let me.
It's still not cold enough. Looking forward to the negative numbers this weekend.
I remember seeing that back in the day a few times car overheating and spraying out the cap because of a frozen radiator. Mostly in trucks. Hopefully you didnt crack a tube in the core or move a frost plug.