Oh dear oh dear http://www.telegraph.co.uk/lifestyle/8539481/Top-ten-festival-tips.html

my favourite:

DON’T bring wellies
With the driest May in living memory, with any luck mud will not be an issue this summer. So leave the Wellington boots on the farm and try espadrilles, flip-flops or deck shoes. That said, this is England, so perhaps pack a waterproof just in case.