Delta teams in the Operations and Customer Center are monitoring weather patterns expected to bring scattered thunderstorms and heavy rain into the East Great Lakes and Ohio Valley region throughout the day Wednesday and into Thursday morning.

As part of that weather system, Delta issued a weather waiver for airports in the Northeast, particularly its New York-JFK and LaGuardia hubs, a couple hundred miles away from the storm, where ground delay programs are expected to help manage air traffic flow.

The airline's Northeast weather waiver may have come as a surprise to some — the weather in New York Wednesday is expected to be mild, with some scattered thunderstorms overnight and into Thursday morning. But the local weather in the Big Apple doesn't tell the full story.

In airspace as congested as New York's, air traffic controllers begin lining up aircraft bound for the New York arrival traffic pattern over the Ohio Valley, hundreds of miles away, funneling flights from every direction down corridors in the sky. The same is true for departures leaving the Northeast.

For safety, flights aren't routed through thunderstorms, so when en route thunderstorms like those expected over the Ohio Valley Wednesday disrupt that flow, it can have a measurable effect on arrivals and departures. Teams in the OCC work closely with the Federal Aviation Administration's Air Traffic Command Center in Washington, D.C. to implement flow programs to manage the volume of traffic despite the challenging en route weather. Delays and a small number of Delta Connection cancellations may result.

Understanding how en route weather can impact flights in another region can help customers adjust their travel plans accordingly.

As always, customers are encouraged to check Delta.com or the Fly Delta Mobile App for the latest flight status.