I've done down in the teens but I really don't like to go much below the mid 20s. I don't have winter riding shoes and my feet just can't take it. Think next year I may just switch to flats for winter. I'm really starting to get burnt out of this winter. It is either freezing, muddy, or way to often both this year. Suppose to hit the mid 50s this Saturday and I'm really looking forward to that.