Hundreds of flights were cancelled or delayed after powerful storms swept across the eastern half of the country, disrupting air travel across the country. The disruption comes at an already challenging time for air travel due to a partial government shutdown that has reduced staffing at some security checkpoints. Nearly 900 flights were canceled or delayed as of Tuesday morning, according to flight-tracking site FlightAware. The Federal Aviation Administration ordered ground stops at Hartsfield-Jackson and Charlotte Douglas International Airport, and delays at JFK and Newark Liberty International Airport. The current partial shutdown affects only the Department of Homeland Security, which includes the Transportation Security Administration. Some airports have reported longer security lines due to staffing shortages, and more than 300 TSA agents have quit since the start of the shutdown.