There were a bunch of nuts out last weekend dressed in all their winter regalia, and it was only in the upper 50s to lower 60s. I was out in a T-shirt, with a windshirt and cycle shorts. I was over dressed, sweating, but the wind warranted the windshirt. Had I been in tights, arm warmers, hat and helmet, I'd have melted.
I did pull out the tights though about mid week, still too much clothing.
Don't like the Full length gloves just yet either, I need to get a set of cycle gloves that will fit over my liners.