Troublesome weather is set to burden up to 56 million traveling Americans over Thanksgiving weekend. Travelers can expect to face winds, rain, and snow as they make their way back after holiday celebrations through Sunday and Monday.

According to forecasts from the National Weather Service, heavy snowfall is expected in central regions, including the Plains, the Midwest, and the Mississippi Valley, with freezing rain expected slightly to the east in the Ohio Valley.

In the southeast and Gulf Coast regions, thunderstorms and general rain showers are expected. The wet weather will persist to the north with rain in the Middle Atlantic and freezing rain in southern New England.

“Freezing rain will be the initial threat for portions of Pennsylvania and New York, as well as the Central Appalachians,” the NWS stated. “Snowfall amounts in the Northeast are currently forecast to be 4 to 8 inches from parts of New York, southern Vermont and New Hampshire, and Massachusetts through Sunday night, with more expected on Monday. Travel impacts can be expected on this busy travel weekend.”

On the West Coast, California is forecast to get hit with more rain following a rash of flooding in the state on Thanksgiving Day.

In response to these forecasts, delays are expected all across the Northeast and South on Sunday and Monday.

American Airlines and Delta have begun waiving fees for flight changes for customers traveling out of major cities like New York, Minneapolis and Boston.

On average, the Sunday after Thanksgiving tends to be one of the busiest days for air travel in the U.S.

Snow blows across a road on November 27, 2019 near Rudd, Iowa
Snow blows across a road on November 27, 2019 near Rudd, Iowa GETTY IMAGES NORTH AMERICA / SCOTT OLSON