If you’re hoping your last-minute Christmas gift will arrive on time, you may be out of luck.

Amazon, the US Postal Service, UPS and FedEx are warning the winter storm hitting large swaths of the United States is disrupting operations in the final delivery days before Christmas.

The US Postal Service said dozens of post offices have been temporarily closed by the storm in South Dakota, North Dakota, Nebraska, Minnesota and Iowa. The agency asked customers to clear snow and ice from sidewalks, stairs and mailboxes to help letter carriers make deliveries.

FedEx told US customers packages expected to be delivered Friday or Saturday could be delayed. UPS said its delays may be somewhat more localized.

Amazon also closed some facilities due to the storm, saying employees at the facilities would be paid for the canceled shifts.

UPS also said air and ground activities are being affected in Louisville, Kentucky, and Rockford, Illinois.