Ron Zirkle, whose flight to Memphis, Tenn., has been canceled due to winter storms, is silhouetted against a snow-covered tarmac, Friday, Feb. 4, 2011, at Dallas-Fort Worth International Airport in Grapevine, Texas, Friday, Feb. 4, 2011. Another blast of winter weather slammed Dallas with up to 5 inches of snow, making driving hazardous and forcing the cancellation of hundreds of flights as tens of thousands of football fans descended on North Texas for the NFL's Super Bowl football game with the Green Bay Packers and the Pittsburgh Steelers at Cowboys Stadium, Sunday, Feb. 6 in Arlington, Texas. (AP Photo/Jae C. Hong)

Photo by: Jae C. Hong

Ron Zirkle, whose flight to Memphis, Tenn., has been canceled due to winter storms, is silhouetted against a snow-covered tarmac, Friday, Feb. 4, 2011, at Dallas-Fort Worth International Airport in Grapevine, Texas, Friday, Feb. 4, 2011. Another blast of winter weather slammed Dallas with up to 5 inches of snow, making driving hazardous and forcing the cancellation of hundreds of flights as tens of thousands of football fans descended on North Texas for the NFL's Super Bowl football game with the Green Bay Packers and the Pittsburgh Steelers at Cowboys Stadium, Sunday, Feb. 6 in Arlington, Texas. (AP Photo/Jae C. Hong)