BILLINGS, Mont. (AP) — Bitter cold wind chill temperatures led school officials in Billings and the surrounding areas to cancel classes on Tuesday.

Schools are also closed in Park City, Lockwood, Shepherd and Custer along with Huntley Project school and schools on the Northern Cheyenne Indian Reservation. Other area schools delayed the start of classes until 10 a.m.

The National Weather Service is forecasting wind chill temperatures as low as minus 40 degrees (-40 Celsius) Tuesday morning.

The temperature in Billings was minus 11 (-24 Celsius) at 7 a.m. with a wind chill of minus 34 (-37 Celsius).

Billings Public Schools Superintendent Terry Bouck says classes will be held on Wednesday.