I went out last night to put a cover on the car windscreen so that the screen didn't freeze up overnight. I was out at about 7pm and all the cars in the street were already completely frozen up.
I spent 10 minutes defrosting the screen and windows and putting the cover on the windscreen.
Imagine my surprise this morning when I came out to the car and found not a single sign of ice anywhere. I can't remember a time when it was so cold in the afternoon that it actually got warmer during the night thereby defrosting the ice that had already frozen.