I got to wear these sooner than I thought when it was in the 40s (F). I had an underlayer as well, although I don't recommend a thin underlayer if there is wind. I was warm and comfortable, especially after I got settled and had pedaled for a bit. I would wear a wind jacket if there is a more than 10 mph gust, but otherwise these are great. I have several of these, thermal and otherwise and have no complaints. They do the job and do it well. Thanks