Airlines in Denver canceled an estimated two dozen flights to and from several East Coast cities Friday as winter storms pounded the Northeast.

United Airlines, JetBlue Airways, Frontier Airlines and other carriers nixed many of the 35 scheduled nonstop departures from Denver to New York, Boston and Philadelphia, according to information on Denver International Airport's Web site.

The moves were among hundreds of overall cancellations into and out of the Northeast on Friday as airlines grappled with snow and ice storms. Chicago-based United said it bagged nearly 200 flights systemwide - or roughly 6 percent of its schedule - because of the storm.

"Basically from late morning onwards almost all the flights into Northeast airports were canceled," said Jeff Kovick, a United spokesman.

The storms are expected to let up today, but carriers said there still could be some operational hiccups.

Denver-based Frontier canceled six of its 10 daily flights to and from Philadelphia and New York. But, as of late Friday afternoon, the carrier still planned to fly its red-eye, overnight flight to each of the cities.

United Airlines - DIA's largest carrier - axed more than a dozen flights to and from Denver, although it did not provide exact numbers.

Airlines are waiving fees and other charges for customers who want to postpone their travel over the next few days and rebook on later flights.

Customers should check with their airlines - rather than the airport - to see whether their flight has been canceled.

"The most important thing to do before you go to the airport is to check the status of the flight or take advantage of our waiver and re-book for a later date," said United spokeswoman Robin Urbanski.

Discount carrier JetBlue, which was widely criticized for its response to storms last month, canceled hundreds of flights, most of them involving departures and arrivals at John F. Kennedy International Airport in New York. It also has canceled flights into and out of New York's LaGuardia, Newark, N.J., and Boston.

JetBlue has been under pressure since some passengers were stranded in planes at Kennedy for more than 10 hours during a storm last month.

The carrier was unable to resume normal operations for days afterward because flight crews weren't where they were supposed to be.

The airline had hoped to get through the storm without canceling flights but later acknowledged it waited too long to ask airport authorities for help getting passengers off the stranded planes.

"We're hopeful the plans we have in place will be effective and allow us to recover quickly," said Sebastian White, a JetBlue spokesman.

"We've always tried to take a wait-and-see approach with the weather . . . believing that people want to get to their destination late, rather than never," White said Friday. But since the Feb. 14 storm - and the maelstrom of complaints that followed - JetBlue has had "a shift in thinking," he said.

In the past month, JetBlue also has unveiled a customer bill of rights that promises vouchers to passengers who experience delays. The airline also ran full-page newspaper advertisements apologizing to customers about the Valentine's Day problems.

Passengers whose flights were canceled Friday were offered refunds or a chance to rebook travel through April 30 without paying a fee for the change, White said.

walshc@RockyMountainNews.com or 303-954-2744.