CHICAGO (AP) — Snow has forced the cancellation of more than 300 flights at Chicago’s international airports on Halloween.

Chicago’s Department of Aviation reports that Midway cancelled 126 flights Thursday morning and delays of 18 minutes. O’Hare cancelled 208 and reported average flight delays of 54 minutes.

National Weather Service meteorologist Todd Kluber told the Chicago Sun-Times that O’Hare was expected to receive up to 3 inches (7.6 centimeters) of snow by Thursday night. Midway could get between 1 and 2 inches (2.5 and 5 centimeters).

The weather service also noted the day has been marked by strong winds and high waves along the city’s Lake Michigan shoreline.

The Chicago Tribune reports that some northern Illinois communities have called off trick-or-treating. Shipshewana and Wolcottville in northwestern Indiana postponed trick-or-treating to Friday.