Trouble with Goodwood at that time of year is that the weather can vary from 'almost hot' to damn-near Arctic, so be warned. First time I went I decided on a t-shirt, shirt, waistcoat and tweed jacket and I cooked!! But if the weather is bad, the wind-chill can freeze you to be bone. It's a flat airfield and the wind can blow in from the coast - not fun. When the rain arrived last year (sorry - monsoon!) the temperature changed from summer to winter and hypothermia became an issue....I now opt for mechanics overalls as you can add or remove clothing underneath, as required