As Hurricane Irene slammed into North Carolina this morning, commuters and travelers across the country are feeling its impact.
More than 8,300 commercial airline flights have already been canceled this weekend, and that number is expected to rise, according to the website, Flightware.com.
All airports in the New York area -- Newark, John F. Kennedy and LaGuardia -- will stop accepting domestic and international arrival flights at noon today.
Public transportation in New York City will stop running at noon, and airport officials do not want arriving passengers to be stranded at the airports.
Operations will be suspended at all New York airports at 10 p.m. tonight.
Sam Schwartz, former commissioner for New York City's Department of Transportation said it will take eight hours to get all the trains and buses tucked safely away.
"They're gonna have to move all of the trains - and remember - we never have a time in which all the trains are placed in rail yards," Schwartz said.
Philadelphia International Airport will shut down tonight at 6 p.m.
Most airlines are now giving out travel waivers, which means they do not charge any fees for changing your flight.
But in many cases, you have to book your next flight within a short window.
In the central terminal at LaGuardia Airport, several passengers are stranded in the food court, trying to plot their next move. Many airport shops and restaurants may close at noon.
The Port Authority of New York and New Jersey said it is ready for potential disruptions.
"Additional staff and contractor employees will be assisting customers as needed in every area of airport operations," said the Port Authority, and they will "stock hundreds of cases of bottled water, diapers, cots, blankets and pillows to provide to stranded passengers if necessary.
Under terms of the agency's concession contracts, at least one food vendor in every passenger terminal must remain open 24 hours so that food is available at any time of day or night."
Despite the fact that thousands of flights have been canceled, the departures area at LaGuardia was packed at 6 a.m. this morning with people trying to get home before they get stranded.
Flights will continue to take off as weather permits.
Raleigh-Durham Airport Authority told ABC News Friday morning about 100 out of 400 flights have been canceled for today at RDU and it anticipates further disruptions for flights along the East Coast through Monday, Aug. 29.
How quickly airports can function after Irene will depend on more than clear skies. If the public transportation in New York is not running, many airport personnel may not be able to get to work.
President Obama cut his vacation short by one day, conferencing with his emergency response team, and warned citizens of the dangers of Hurricane Irene.
"I cannot stress this highly enough: If you are in the projected path of this hurricane, you have to take precautions now. Don't wait. Don't delay," Obama warned Friday morning from Martha's Vineyard, urging citizens to visit ready.gov if they are not sure how to prepare.
Amtrak has canceled most trains traveling south of Washington, D.C. for Saturday and Sunday.
The railroad announced at 5:40 p.m. EST Friday it is canceling more East Coast trains with service reductions beginning on today and will not operate trains in the Northeast on Sunday.
Amtrak may make additional announcements as the storm travels north.
Most cruises set sail on weekends, so the ships that had already departed were clear of the storm by the time it made landfall, said Paul Motter, editor of CruiseMates.com.
However, all the major cruise lines have altered their schedules to some degree.
Carnival Cruise Lines As of 10 a.m. today, Carnival announced changes to cruises departing this weekend to the Bahamas and Key West, updating guests and suggesting they continue checking the company website.
Carnival Pride has been directed by the US Coast Guard to arrive early from the previous cruise and proceed to a secure, alternate location until the storm passes.
Celebrity Cruises Celebrity Summit did not depart Kings Wharf, Bermuda, Thursday at 6 p.m. Instead, the ship will remain in Bermuda until 5 p.m. Friday, Aug. 26. As of Friday morning, the cruise line anticipates the ship will arrive in Bayonne, New Jersey, on Aug. 29.
Holland America HAL's Veendam which left August 21 for a seven-day Bermuda Cruise, departed Bermuda at 5:00pm on Thursday, Aug. 25, and is scheduled to arrive in New York one day early on Saturday, ahead of the storm's anticipated arrival, as of 10 p.m. PDT Thursday.
Norwegian Cruise Line The cruise line announced Friday at 2 p.m. EST changes to the schedules of the Norwegian Jewel and asked travelers to check the companies website.
Royal Caribbean'sExplorer of the Seas will depart Cape Liberty, Bayonne, New Jersey, on Saturday at 4 p.m., one hour earlier than originally scheduled.
On Friday at noon EST, it also cancelled Majesty of the Seas' call to CocoCay on Saturday and Monarch of the Seas' call to CocoCay on Sunday.
The safest location for a ship during a hurricane is at sea, well away from the storm. A ship should never be in port when a storm hits, because the vessel can be dashed against the pier and sustain damage, he said.
The biggest challenge comes when a hurricane makes landfall the same day that the ship is scheduled to be in its U.S. home port, Motter said. Cruise lines will usually opt to keep ships out to sea until "the coast is clear." The passengers get an extra day of "fun," although the seas may be rougher than usual.
Motter said the worst part of a hurricane during a cruise may be the airline reservation chaos passengers face when they disembark a day later than planned.
Dennis Powell and Stephanie Smith contributed to this report.