One of the busiest U.S. travel days of the year also looks to be the most difficult, as bad weather in the northeastern states has already forced mass flight cancellations.
As of 2:15 p.m. ET Wednesday, FlightAware reported 596 flights into, out of or within the United States had been canceled ahead of a storm expected to bring rain and snow from Washington to Boston. Over 2,500 flights have been delayed, the site said.
Around one-third of those flights were meant to have originated at either New Jersey's Newark or New York's LaGuardia airports. By 2:15 p.m. ET flights into those two airports were delayed an average of more than three hours. New York's John F. Kennedy International Airport reported average delays of an hour and a half for inbound flights.
Philadelphia International Airport, also set to see the effects of Winter Storm Cato, saw average inbound flight delays of an hour and 43 minutes by that time.
"The delays will begin accumulating early afternoon as the worst of the weather impacts the Northeast and will continue to cascade through the evening," FlightAware CEO Daniel Baker said in a statement.