i commute in colorado all year. 25 miles a day, every day.

hada -20F day last year.

i wear arm and knee warmers below 60, full finger gloves and a thermal cap below 50, full length bib tights, wool socks, base layer, midlayer and shell below 40, lobster gloves, defroster bike shoes and bala below 30... below that its just adding more and more layers as necessary.