Take a cardigan, wear a blazer or just throw on an over sized sweater. Better yet wear a gorgeous coat and just leave it in the coat check.
Stockings! There is no need to freeze just to show off your stems. Your look may even look that little more polished with a set of chic black stockings. Here is the important part, look out for the denier (that's the thickness) If you want a really warm set of stockings then a higher denier is better. I wear at least 70 but I have seen them go up to 200 denier.
Boots! Oh so in right now AND you can sneak a pair of socks under them to keep your tootsies real cosy like.
Lastly, for that extra little bit of warmth you cant go past a street cuddle with the boy you took out (or just found ;)