Airlines have canceled 271 flights so far today as rain and snow move through the U.S. East Coast on the eve of Thanksgiving.

Most of the scrubbed flights were at New York City-area airports and involved regional carriers operating express flights for major airlines, JetBlue Airways Corp., which is based in New York, and the Delta Shuttle between Boston and LaGuardia airport, according to FlightAware.

While the number of canceled flights as of 8:17 a.m. in New York isn’t particularly large, due to the holiday planes will be packed tightly, leaving little extra room to accommodate displaced passengers.

Even worse than the eliminated flights could be the “thousands of delays that will cause moderate disruption to Thanksgiving travelers,” according to a statement from FlightAware, an online flight tracking service.

Two days ago United Continental Holdings Inc., American Airlines Group Inc. and Delta Air Lines Inc. all waived their customary fees for flight changes for travel today through about two dozen northeastern airports, allowing passengers to rebook flights for yesterday or tomorrow, in an effort to ease congestion ahead of projected storms.

Weather predictions over the past two days have varied from almost nothing falling in the large East Coast cities, including New York, to as much as 8 inches (20 centimeters). The difference is because of uncertainty on where rain will leave off and snow will begin.

As of last night, forecast for New York calls for snow starting about midday, with 4 to 6 inches accumulating in the northern part of the city and 2 to 4 in the south. As much as 10 inches are predicted in some areas of northern New Jersey through the lower Hudson Valley and central Connecticut.

The Thanksgiving holiday period, which runs through Nov. 30, is the among the busiest travel times in the U.S. Air passengers are expected to rise to the highest level since 2007, totaling 3.55 million, a 3 percent increase from a year earlier, according to AAA, the motoring club.

–With assistance from Brian K. Sullivan in Boston and Michael Sasso in Atlanta.

To contact the reporter on this story: Molly Schuetz in New York at mschuetz9@bloomberg.net. To contact the editors responsible for this story: Ed Dufner at edufner@bloomberg.net.

Photo Credit: Travelers wait in lines to pass through security and get to their gates at LaGuardia Airport in New York, Tuesday, Nov. 25, 2014. Seth Wenig / Associated Press