Multiple winter storm warnings have been issued in five different states, with some advising people to avoid travel.

Winter storm warnings are in effect for several parts of Oregon, Washington, Idaho, Wyoming and Montana, with heavy snowfall expected in all of these states.

Almost all warnings advise people not to travel under these conditions.

Oregon

Several warnings affect counties in the southeastern part of the state, with some extending into California. One includes Highway 97 near Mount Hebron, Medicine Lake and the Warner Mountains, on Monday from 4:00 PM to 10:00 PM PST.

Another, on Mondays from 1:00 PM to 10:00 PM PST, includes portions of highways 58, 230, 138, 62, 140 and 66.

The Medford National Weather Service (NWS) said, “Travel may be very difficult to impossible. The hazardous conditions could impact Monday morning and evening commutes. Strong winds can cause extensive damage to trees and power lines.

“If you must travel, make sure you have an extra flashlight, food and water in your vehicle in case of an emergency.”

“People should consider postponing all travel,” the NWS said. “Motorists should exercise extreme caution if travel is absolutely necessary.”

Meanwhile, a separate winter storm warning is in effect for eastern Douglas County Foothills County – Monday from 1:00 PM to 10:00 PM PST.

Portland’s NWS issued a winter storm warning for the western reaches of the northern and central Oregon Cascades on Monday from 4:00 PM to 10:00 PM PST, with heavy snow expected.

“Travel can be very difficult,” the agency said. ‘Spry blowing snow can significantly reduce visibility.

“Significant snowfall with periods of heavy snow combined with poor visibility will create very difficult driving conditions,” forecasters said.

Pendleton’s NWS said, “If travel is absolutely necessary, drive with extreme caution. Consider bringing a winter storm pack, including things like snow chains, jumper cables, flashlights, shovel, blankets and extra clothing.

‘Also take water, a first aid kit and anything else that can help you survive if you get stranded.

“Do not touch downed lines and report any power outages to your electric company. Travel is strongly discouraged due to slippery roads and the possibility of downed trees and power lines.”

Washington

In Washington, a winter storm warning is currently in effect for Mazama, Holden Village, Loup Loup Pass, Stehekin, Winthrop, Conconully, Methow, Twisp and Stevens Pass until 10:00 PM PST on Monday.

“Motorists should use extreme caution if travel is absolutely necessary,” the Spokane NWS said.

Another warning covers Dobson Pass, Mullan, Osburn, Lookout Pass and the Fourth of July Pass until 10:00 PM PST on Monday. Heavy snow is expected, with the NWS stressing that “travel over Lookout Pass may be very difficult.”

Meanwhile, a winter storm warning is in effect from 5 a.m. Saturday on Sunday to 10 a.m. PST on Monday, covering slopes and passes for much of the Cascades.

“Roads, especially bridges and overpasses, are likely to become slippery and dangerous,” the Seattle NWS said.

Idaho

Heavy snow is also expected in Idaho, with a winter storm warning over the Centennial Mountains, in Island Park, from 5:00 PM Sunday to 8:00 PM MST Monday.

The Pocatello NWS said, “Travel may be very difficult. The hazardous conditions may impact commutes Monday morning and evening.”

Wyoming

A winter storm warning is in effect from 10am Sunday to 10pm MST Monday in the Teton and Gros Ventre Mountains.

Heavy snow is expected, with total snow accumulation expected to reach 20 inches at the highest elevations.

The Riverton NWS said, “Travel may be very difficult to impossible. The hazardous conditions may impact travel over mountain passes, such as the Teton and Togwotee passes.”

Montana

A winter storm warning is in effect for I-90 Lookout Pass to Haugan until 11 a.m. Sunday. Heavy snow is forecast day and night.

The Missoula NWS warned of “dangerous or impossible travel conditions.”