Amtrak has suspended some of its train services through the end of the week due to a massive winter storm sweeping across the nation. 

In a news alert on Wednesday, Amtrak said that it has suspended some Midwest and cross-country routes through Sunday. 

The railroad service said a number of long-distance trips inbound or outbound from Chicago and other Midwestern hubs will be canceled.

“These actions are with abundant caution and in consultation with state transportation departments, host railroads, emergency managers, and weather forecasters,” Amtrak said in a service announcement. 

Railroad officials said on Thursday that its Northeast Corridor, the nation’s busiest railroad line, will still continue on schedule unless the ongoing weather conditions continue to get worse, according to The Washington Post. 

The Amtrak delays come as more than 1,500 U.S.-based flights were canceled on Thursday due to the massive winter storm, according to data from aviation company FlightAware. Many airports in the Midwest have announced the cancellation of flights in the coming days.

The massive winter storm has brought arctic cold temperatures, heavy snow and heavy wind chills as millions of people in the Upper Midwest and the Plains have been placed under blizzard and winter weather warnings, with the system heading toward the East Coast just days before Christmas. 

Major U.S. airlines have already announced waivers for passengers in cities affected by the storm to rebook their flights for a later date once the storm passes.