A cold 3C (37F) but after the first couple of minutes, I was fine in shorts and a windproof jacket. I guess it is just a matter of acclimating your body to the weather changes and you can tolerate more: had I tried to ride in shorts on a 3C day in August, I wouldn't have made it out the house, let alone down the road. The weather was clear but it is forecast for rain this evening, I hope it will hold off until after I get home.