ct-chicago-flight-cancellations-Fliers faced several trouble spots Tuesday as cold air moved east and south out of the Midwest. More than 800 flights had been canceled nationwide as of 5 p.m. ET, according to flight-tracking service FlightAware. Several major airports in the mid-Atlantic and Midwest were seeing above-normal delay and cancellation tallies. Tuesday’s flight disruptions were concentrated at five airports: Washington Reagan National, Philadelphia, New York LaGuardia, Newark Liberty and Chicago O’Hare. American operates a hub at three of those airports while United has hubs at two of those. At Washington’s National Airport, where 2 inches of snow fell Tuesday morning, nearly 190 flights had been canceled as of 5 p.m. ET. That cancellation total accounts for about 20% of the airport’s daily flight schedule, according to FlightAware. Delays also were a problem, with more than 300 flights – or about a third of the day’s schedule – suffering delays. Combined, more than half of Tuesday’s flights at D.C.’s close-to-downtown airport were either delayed or canceled. More