What the hell is up with the weather???

Don't even get me started on global warming and all that, but what has happened with the weather in the last couple of days? Last week it was snowing and now it's 20 Celsius in London. I'm in a T-shirt and sweating (mildly). And they're forecasting it's going to be even better this week-end! Which is great news don't get me wrong, but I'd planned a serious week-end of camping on my sofa watching motorsport around the world (Australia/USA/Malaysia). And this great weather is already making me feel guilty about (possibly) staying indoors for 2 days. I feel I should go and mow the lawn or something. How is it around the rest of the world?