If you’re flying Southwest Airlines this weekend, make sure to check your flight before you leave for the airport. An air traffic control issue combined with weather delays on the East Coast have caused problems across the airline’s network, forcing the Dallas-based carrier to delay and cancel hundreds of flights.  By Saturday afternoon, the flight-tracking website Flight Aware showed Southwest with 568 cancellations and 717 delayed flights nationwide.  “Air Traffic Control (ATC) issues and disruptive weather have resulted in a high volume of cancellations throughout the weekend as we work to recover our operation. We appreciate your patience as we accommodate affected Customers as quickly as possible,” Southwest said in an emailed statement.  After receiving pushback to that initial statement…