We are already in the south of France, not camping at the moment. But we are due to head to the Pyrenees today, for 7 nights, camping with a camper and two young children. Its pouring now. And the forecast is for this to continue for days! The campsite we booked is beside a lake, with canoeing and fishing etc, very rural, not a lot else to do than enjoy being outside etc. we can't put the camper up easily in the rain.
So what would you do? I am all for canceling the first few days until the weather improves a bit, packing a lot more warm clothes and waterproofs. DH is a bit more gun ho about camping, he's a lot more used to roughing it than I am (does lots of hikes with his students and they go, whatever the weather).
How bad does the weather / forecast have to be to make you cancel / delay / change your plans?