In his book "How to Fly" Gordon Baxter mentions a useful safety device.
He handed me a small blue card with a hole cut in the middle of it. "This is your blue card instrument ticket. With this not even you could get into trouble. Before you start hold this blue card up against the sky. Look through the hole. If the sky is not the same colour as the card, don't go."
And if you are going to ignore his advice and fly up a valley surrounded by cumulogranitus, make sure it's a big one you can turn round in!
Chamonix below, the highest mountain in Europe to the right.
Mike