Early Riser by Jasper Fforde
This is an unusual, quirky book by the author of the Thursday Next series, set in an alternate Wales. Charlie Worthing has just joined the Winter Consul Service and heads out on his first assignment, only to get trapped in Sector 12 when the trains stop running. Winters are so long and bitterly cold that most people hibernate, bulking up before their long sleep. Some unfortunates turn into Nightwalkers, sort of zombies who can work menial jobs. Charlie has many adventures as he tries to make it through his first winter awake and investigates a viral dream about a blue Buick. Darkly humorous and witty with an appealing protagonist.