HELENA, Mont. (AP) — Temperatures plunged across the Rocky Mountains on Monday as residents in Montana dug out from a wintry blast that left several feet of snow and caused the governor to declare an emergency.

Freeze warnings were in effect in parts of Utah, Idaho and Wyoming, with temperatures forecast to drop into the teens and 20s. The cold set in with the lingering fall storm system that dumped snow for three days across much of central and western Montana, including over 4 feet (1.22 meters) on the Blackfeet Reservation.

While parts of the Rockies were dealing with frigid temperatures and unusually early snow, extreme wildfire danger warnings emerged in eastern Utah and much of Colorado on Monday, where temperatures as high as the mid-80s (30 degrees Celsius), along with gusty winds and dry air were expected to create critical fire conditions.

Montana Gov. Steve Bullock declared an emergency Sunday for areas hit by the early-season storm that brought heavy, wet snow and high winds that closed roads, downed trees and caused scattered power outages.

The declaration allows the state to mobilize resources to help affected areas.

The snow and bad roads led to school closures Monday in the northern towns of Browning, Choteau, Conrad, Cut Bank, Dutton-Brady, Fairfield, Shelby, Augusta and Valier.

Augusta school superintendent Matt Genger said the decision to close down on Monday was made because of the treacherous roads.

"I think our furthest student is 30 miles away," he said.

Genger said he doesn't remember any other snow day occurring this early in the school year. The only school closure in September that he could recall was for a wildfire in the mid-1980s when the Red Cross and U.S. Forest Service needed a staging area and shelter.

Blackfeet and Pondera emergency officials on Sunday requested all non-emergency vehicles stay off the roads until further notice.

Snow drifts shut down the U.S.-Canada border crossing at U.S. Highway 89, where state transportation officials also reported that 200 head of cattle were on the roadway. A vehicle accident slowed traffic on Interstate 15 and several surrounding state highways were closed because of the snow.

The National Weather Service issued both freeze warnings and extreme wildfire danger warnings in Utah. The hard-freeze warnings in the western part of the state are expected to last until Tuesday, meaning outdoor plumbing and crops that have no protection could sustain significant damage.

The fire warning is in the eastern part of the state near Moab through Monday evening.