Amtrak said it is running Wednesday on a modified schedule on its Northeast Corridor lines because of the extreme cold weather that is sweeping the country.

Acela Express and Northeast Regional service between Washington and Boston will operate with reduced frequencies, Amtrak said.

There are also schedule changes for Amtrak’s Empire Service between New York City and points west of Albany, along with Keystone Service between Harrisburg, Pa., and New York.

Commuters and travelers have had to deal with days of cancellations and delays because of the severe cold weather.