Airlines have already canceled nearly 500 flights for Monday as a late-season snowstorm threatened to make a mess of air travel this week.

WFMY News 2 was on scene at Piedmont Triad International Wednesday morning and captured a quiet day without the usual airport hustle and bustle.

Unfortunately for fliers, those tallies were likely to soar. Southwest, for example, said it expected to ground nearly all of its flights in the Northeast on Tuesday. Other airlines may make similar decisions with blizzard conditions forecast to hit New York City's airports and heavy snow expected across much of the region.

All big U.S. airlines have waived change fees to customers ticketed to fly to airports in the storm’s path. The details varied by carrier, though they generally allowed customers to make one change to their tickets without paying change fees that typically cost $200 or more. (Scroll down for links to policies now in effect)

FLIGHT TRACKER: Is your flight on time?

The preemptive cancellations and weather waivers come as the storm was expected to hit its peak in the Northeast on Tuesday. Snow was also forecast in Chicago, where flights were already being disrupted.

But the worst weather-related problems were expected at airports serving New York, Philadelphia, Washington, Boston and Baltimore. All were likely to see major schedule disruptions if forecasts are accurate. Dozens of smaller airports in the region also could be affected, with some possibly struggling to remain open if snowfall totals of 12 to 18 inches pile up across the region.

Nationwide, carriers had grounded 500 flights for Monday as of 3:30 p.m. ET on Sunday, according to flight-tracking service FlightAware. For Tuesday, nearly 120 flights had already been scrapped by Sunday afternoon with hundreds more likely to come.

Most of Monday’s preemptive cancellations had so far come in Chicago. Southwest alone had grounded more than 250 flights Monday at Chicago Midway, which is one of the carrier’s busiest bases.

At O’Hare, American had grounded about 200 flights Monday on its regional affiliates. The company was canceling some late Sunday arrivals to O’Hare operated by its regional affiliates, American spokesman Ross Feinstein said to Today in the Sky. For Monday, the airline anticipated all of its O’Hare flights on regional affiliates would be canceled until noon CT and would gradually resume after that. American anticipated trying to operate most of its “mainline” schedule there Monday.

Come Tuesday, however, heavy snow and blizzard-force winds in the Northeast seemed certain to create widespread problems.

Southwest anticipated that it would suspend nearly all of its Northeast schedule Tuesday, spokeswoman Melissa Ford said in a Sunday e-mail to Today in the Sky.

Southwest would begin halt some evening flights to the region Monday, but Ford said the airline expects that it will not operate any flights Tuesday at a dozen of its Northeastern airports (Albany, N.Y.; Baltimore; Boston; Hartford, Conn.; Long Island/Islip, N.Y.; Manchester, N.H.; New York LaGuardia, Newark Liberty; Philadelphia; Providence; Portland, Maine; Washington Dulles and Washington Reagan National).

That would leave Buffalo, Pittsburgh and Rochester, N.Y., as Southwest’s only airports in the Northeast expected to have service Tuesday -- though Southwest's Buffalo schedule was expected to be limited.

More airlines were expected to details service reductions for Monday and Tuesday, so travelers ticketed to fly this week should keep an eye on flight schedules.

Links to the latest airline winter weather waivers:

Alaska Airlines

American Airlines

Delta Air Lines


Southwest Airlines

Spirit Airlines

United Airlines

Virgin America

Check out the Flight Tracker on the WFMY News 2 mobile app to see the status of your flight.