Flights at Denver International Airport were delayed by an average of 46 minutes Wednesday evening after thunderstorms prompted a ground delay, according to a Federal Aviation Administration alert.Officials ordered the ground de lay around 4 p.m. and set it to expire around 9 p.m. The National Weather Service Boulder said in a 3:35 p.m post that thunderstorms were "numerous" across the area.More than 400 flights into or out of DIA have already been delayed, according to Flight Aware. One has been canceled as of 5:30 p.m. ...read more read less