SIDNEY, Neb. - The Extreme Cold Warning issued by the National Weather Service Sunday remains in effect until 11 a.m. Tuesday, covering portions of the Nebraska Panhandle and east-central, south-central, and southeast Wyoming.

The warning affects Dawes, Box Butte, Morrill, Northern Sioux, and Southern Sioux counties in Nebraska, as well as Converse, Niobrara, Central Carbon, Southwest Carbon, and the Upper North Platte River Basin in Wyoming. Dangerously cold wind chills as low as 35 below zero are expected, with frostbite and hypothermia setting in quickly for anyone exposed to these conditions without proper protection. Residents are urged to dress in layers, including hats, gloves and face masks, and to avoid outdoor exposure whenever possible.

A Cold Weather Advisory is also in effect for the rest of the Nebraska Panhandle, northeast Colorado and southeast Wyoming.

In response to the extreme cold temps, numerous schools and institutions have adjusted their schedules for Tuesday. Banner County Public Schools will have a two-hour late start, with buses running accordingly. Bayard Public Schools will start at 10 a.m., with no breakfast or half-day preschool. Chadron State College will open its campus and begin classes at 11 a.m. Garden County Schools in Oshkosh will start at 10 a.m., with no morning preschool or breakfast; buses will leave pick-up sites at 9:25 a.m. Kimball Public Schools will also start at 10 a.m., with PreK classes running from 10 a.m. to 12 p.m. and 1:15 p.m. to 3:15 p.m., and buses running accordingly. Peetz Schools, Leyton Public Schools and Potter-Dix Public Schools will both start at 10 a.m. on Tuesday, with buses and vans running as scheduled but no breakfast provided. South Platte Public Schools will start at 10 a.m. Valley RE-1 in Sterling, Colorado, will have a two-hour delayed start.

Additionally, all Monday night classes for Just for Kix in Sidney were canceled due to the cold weather.

Tuesday's forecast is expected to be slightly warmer, with increasing clouds and a high near 39 degrees, along with west winds around 15 mph.