American and Southwest grounded on Wed. temporarily. They shut down the Air Traffic Controllers building for disinfecting and cleaning for approx 1-2 hours. Flights cancelled and delays big time. As of Thursday morning Southwest was almost back to the norm. with only 4 delays reported from the shut down while over at DFW, American still reported 55 cancellations with 28 delays from the shut down. With the current weather in Tx and the wintry mix just west of 35, it may take another day or two to clear up all the cancellations and delays and get back to the norm.
https://www.yahoo.com/news/flights-being-halted-2-major-225216348.html
https://www.yahoo.com/news/flights-being-halted-2-major-225216348.html