Freezing rain, snow, ice and thunderstorms were wreaking havoc for millions of holiday travelers from the Louisiana Gulf Coast to eastern Canada early on Sunday, as a huge and deadly storm system moved east in time for Christmas.

“This is a particularly strong storm with very warm, near record-breaking temperatures in the East and very cold air in the Midwest, and that contrast is the sort of conditions that are favorable for not only winter weather but also tornadoes,” National Weather Service meteorologist Ed Danaher told Reuters.

The bad weather was complicating travel for the 95 million people that travel agency AAA estimates will fly or drive for the holiday.

“We’ve had pretty poor weather conditions two weeks in a row leading up to Christmas,” Christopher Dolce, a meteorologist at the Weather Channel. “There’s been a considerable amount of winter storm activity all the way back to the days before Thanksgiving and a lot of travel woes continuing into December.”

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