If you’ve never passed a winter in Chicago, let me describe it: You can live for a hundred straight days beneath an iron-gray sky that claps itself like a lid over the city. Frigid, biting winds blow in off the lake. Snow falls in dozens of ways, in heavy overnight dumps and daytime, sideways squalls, in demoralizing sloppy sleet and fairy-tale billows of fluff. There’s ice, usually, lots of it, that shellacs the sidewalks and windshields that then need to be scraped.