A winter storm sweeping across the northeastern US has forced airlines to cancel nearly 400 domestic and international flights, with many more delayed, according to airline tracking service FlightAware.

New York’s three major airports LaGuardia, John F. Kennedy International, and Newark Liberty were among the most affected.

According to Bloomberg’s report, heavy snow is expected to fall across New York City and Long Island from Friday afternoon through Saturday, with accumulations of as much as eight inches (20 centimeters) before the system weakens, Richard Bann, a forecaster at the US Weather Prediction Center, said late Thursday..

City officials issued a travel advisory for the duration of the storm, warning that cold temperatures will slow snowmelt and increase the risk of hazardous road conditions.

Snow totals of four to eight inches are forecast for New York City’s five boroughs, Westchester County, southern Connecticut, and northeastern New Jersey, as the storm moves through the region from about 4 p.m. Friday until early Saturday afternoon, according to the National Weather Service.

“The hazardous conditions could impact the Friday evening commute,” the agency said in a statement.

The winter weather advisory extends south to Philadelphia, with the storm expected to move offshore into the mid-Atlantic by Saturday morning. As it shifts southward, snow is likely to transition into freezing rain.

Another, potentially stronger, cold front is forecast to move across the Northeast including the Washington area toward the end of the weekend, bringing blustery conditions during the final days of the year.

In western Pennsylvania, parts of the region may face an ice storm, raising the risk of power outages and further travel disruptions, the weather service said.