Or any other time, as far as I'm concerned. One of my all-time favorite comfort reads have to be Mary Stewart's classic romantic suspense novels of the 50s and 60s. (I make one allowance for the 70s for Touch Not the Cat. Best love story ever.) I discovered her as a teenager, and fell in love with her romantic locales, feisty, independent heroines, and swoon-worthy heroes--many of the cerebral variety. Over the last couple of years I've been collecting early editions published by Morrow.
None of them is particularly valuable; a couple are old library editions, but I think they're gorgeous. And there's nothing like curling up with one on a rainy night. For other Stewart fans out there, please see this terrific site by Jennie and Julie, who also have a companion blog for all things Lady Mary.
♥ ♥ ♥