CHICAGO (AP) — The Chicago Department of Aviation says weather in the Midwest and around the country is causing delays at the city’s airports.

Department spokesman Gregg Cunningham said Wednesday morning that more than 100 flights were canceled at O’Hare International Airport and delays for inbound and outbound flights were about 30 minutes. At Midway International Airport, delays averaged 30 minutes and more than 20 flights were canceled.

A major winter storm is expected to blow east into the Plains states through Christmas Day.