As the Northeast prepares for a historic blizzard, major airlines are proactively canceling thousands of flights.

Delta, American, and United have already begun processing cancellations at critical hubs like JFK, LaGuardia, Newark, and Boston Logan to ensure operational safety as heavy snow and 50 mph winds approach.

JetBlue, which operates major hubs across the Northeast, has begun preemptively canceling flights ahead of the Nor’easter.

More than 2,500 U.S. flights have already been canceled through Monday. That number is expected to continue to surge in the next 24 hours.