The wind does it for me. If it is still, I can take it pretty low. As soon as there is even a crisp breeze I get cold pretty fast.

Depends on the wind for me. today it was 42 and I wore a long sleeve tee shirt while changing the oil on my truck. I then cleaned up the dog poop in the yard, took out all the bedding in the duck coop and replaced it. The wind pick up to around 8 mph and all of a sudden I was freezing.