I took this picture one midday last week and, as you can see, on my side of the valleys the sun hasn't reached the overnight frost. The Cotswold stone walls are still covered and it was freezing.
What I had spotted was some lunatic balloonists travelling across the main town, madness I thought, if I'm frozen at ground level what would the temperature be at that altitude. I suppose they had their own heater to warm their hands on every time they set the burners off.
I think I will keep my feet firmly on the ground, although knowing my luck I might slip over on the frost and ice. View with the dark surround if you have time.