After nearly being blown into a ditch miles from anywhere in a Michigan blizzard, my winter gear in the back of my Jimmy consists of snowshoes, camping stove, sleeping bag, winter gloves and hat, and Gore-Tex raingear. The snowshoes are the only things that go out of the truck in spring.
And I have needed all the rest of that stuff at one time or another at our notorious early-spring dressage shows. :)