Whenurhappy
Then I guess you'll be the only one judging by the number of suit carriers that are appearing at MB on a daily basis!
As I understand it No 1s are only required for the "party" part, otherwise No 2s (which means you could wear no tie and a short sleeve shirt rather than a scabby woolly pully ....). With any luck it will be 80 degrees just to see who has to hide the fact they can't do up their trousers under a woolly pully....