"Winter"; as in below freezing I'll be wearing, in order head to toe:

-Helmet with a wind cover blocking the vents
-Ski goggles (stop eye tear-ing)
-2 balaclavas: A merino wool on with a mouth covering, and then a pearl izumi
-Voler winter rated jacket, got it on sale a while back and it is very warm on its own down to 10-15F
-Upper base layer
-Pair of gloves, I found a new favorite pair of fingered gloves that work on their own down to the teens F
-2X pair of therma-fleece bib tights, possibly with a windbreaker pant over them
-Lake MXZ400 winter SPD boots....depending on how low the temps are either basic athletic socks or merino wool socks. These boots are just too warm above freezing.