TREDYFFRIN TWP., Pennsylvania (WPVI) -- Millions of travelers are dealing with delays and cancellations at airports and train stations as a winter storm sweeps across the United States. Experts say road travel will become even more dangerous on Friday.
The latest from the Pennsylvania Turnpike Commission estimates 5.4 million people will travel the Turnpike from Friday, December 23 through January 2.
"The weather is horrible out here today," said Sherry Worley of York, Pennsylvania. "We're coming from York. We've seen a lot of rain, snow, turned back to rain again."
Experts say roadways will be slick during peak holiday travel as temperatures drastically drop.
"We're hoping we can keep them dry as long as we can before those temperatures drop because anything that's wet is going to freeze," said PennDOT spokesman Brad Rudolph.
If you're traveling by train, Amtrak an alert, "Severe winter weather forecasted for the Upper Midwest already lead Amtrak to make several service changes and cancelations leading up to Christmas."
Kathleen Ellison was hoping for a smooth trip from Philadelphia to Atlantic City for her holiday break.
"I have grandkids going. It's their first train ride, so it's like something for the holiday," said Ellison. "We're leaving today and we'll come back Tuesday."
At airports, officials urge flyers to arrive early.
"We're certainly paying very close attention to that. Things are going well here. We only have a handful of cancellations, so far, this morning," said Chief Operating Officer for Philadelphia International Airport Keith Brune.
Theresa Graham came up from Florida.
"Weather has really been a factor as it relates to getting from Atlanta to Philly," said Graham.
Travel experts say expect to see cancellations and delays ramp up starting tomorrow.
FlightAware.com has more than 1,600 cancelations for Friday.