TRAFFIC ALERT: All southbound lanes of the Dallas North Tollway are closed at I-635. The North Texas Tollway Authority is urging drivers to avoid the area and expect significant delays during the evening commute. Texas Sky Ranger flew over the scene, where debris is visible in the roadway and traffic is very backed up. We're working to learn what led to the closure and will update this story as more information becomes available. #DallasTraffic #DallasNorthTollway #DFWTraffic #NorthTexas