I landed in Chicago in the middle of a February heat wave that lasted about five days, three longer than my weather app had forecast. I'd packed cashmere sweaters, but the mercury hit the 50s and 60s, setting a single-day record and leaving me, a lover of cold winter days, disappointed. I was, by far, in the minority. Locals streamed to Lake Michigan to bike, jog, and stroll along the 18.5 miles o...