From a surprising heat wave in California to blizzards burying parts of the Midwest and storms rolling over the East Coast, chaotic weather put more than half the nation's population in the path of extreme conditions Monday. Airport delays and cancellations piled up in some of the nation's largest airports, with almost 13,000 flights canceled or delayed across the U.S., and many schools closed early in the mid-Atlantic states, where high winds were in the forecast.On Tuesday, tracking service FlightAware said that as of 6 a.m., more than 2,100 flights had been canceled or delayed.…