SAN FRANCISCO (KGO) -- With Christmas now just days away, holiday travel is picking up at airports across the country.
This comes as a massive and powerful winter storm is bearing down on tens of millions of Americans.
The storm is on track to blow through several major cities, including Chicago, Detroit and New York.
All major airlines say Thursday and Friday are the busiest air travel days and that's exactly when the storm is hitting.
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Blizzard conditions, dangerous winds and freezing temperatures are in the forecast, possibly causing travel ripple effects across the country.
Because of this, the National Weather Service is already telling people in Chicago, parts of Indiana and Ohio to reconsider any travel tomorrow.
The good news is that airlines are offering waivers for free changes right now, giving folks the opportunity to switch flights ahead of the storm.
"Most airlines, especially if it's weather-related, will usually email you or text you like the day before and give you the option of changing your flight," said Art Nittskoff, president of Gamble America.
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Travel experts warn that the combination of airlines reducing the number of flights and travel demand growing to pre-pandemic numbers means flights are up to 95% full.
That means that if yours gets canceled, be patient as it could be difficult to re-book.
For folks traveling by car to their holiday destinations, AAA says Friday, Dec. 23 is expected to be the most congested day on the roads, followed by Dec. 27, Dec. 28 and Monday, Jan. 2 as travelers mix with commuters.
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