I've always just used my general winter clothes for winter commuting, but am getting pretty tired of that.
Route is 17 miles each way. Temps get down to about 20º F (-7º C) at the lowest, although will usually be closer to freezing when I'll be riding. I have a set of fleece pants and a warm lightweight jacket that I don't mind layering with all of the below occasionally.
My goal is to have the fewest items that cover the most situations with proper layering. Don't mind paying a bit extra for performance and durability. Don't care much about looks, although you can't go wrong with black.
I go for Merino wool wherever possible for skin-contact clothing - seems to have the widest comfortable temperature range of what I've used.
Thanks for any input!
This is roughly along the lines of what I wear and I think you will do fine at 20F and even a bit below. All the best