The Federal Aviation Administration (FAA) canceled a brief nationwide ground stop requested by American Airlines (AAL) on Christmas Eve, one of the busiest travel days of the year.

"A technical issue is affecting American flights this morning," American Airlines said, according to reports. "Our teams are working to resolve the issue as quickly as possible, and we apologize to our customers for the inconvenience."

Americans are expected to travel in large numbers this holiday season. The American Automobile Association (AAA) earlier this month estimated that more than 119 million people will travel at least 50 miles from home between Dec. 1 and New Year's Day, topping a record set in 2019. More than 7.8 million of those were expected to to fly, AAA said.

Forecasters expected snow and rain in the Northeast and other parts of the U.S. through early Wednesday, according to National Weather Service maps published Tuesday morning, with thunderstorms in parts of California and some states along the Gulf of Mexico.

American shares were down less than 1% about an hour before the opening bell Tuesday. They are up about 25% this year.

—David Marino-Nachison contributed to this article.