The agency issued an alert yesterday afternoon to area airports, law enforcement agencies and pilots to report anything relevant.
The area airports and other ports of entry were also the scene of heightened security.
Many had been stranded since Friday night, or early Saturday morning after all three area airports closed.
Several private bus companies also operate shuttles to area airports.
Traffic through the three metropolitan area airports increased by a similarly small but notable amount since last year.
He said, for example, they avoided a damaging competition among area airports by assigning different aviation responsibilities to each.
The snow and near freezing temperatures caused mounting delays of up to five hours at metropolitan area airports.
Centers were set up at two area airports over the years, before Bradley became the main site in 1947.
The agency also will continue planning rail links to all three area airports.
That's if I want to be able to pick up my passengers in the city or at area airports.
