A pair of storm systems sweeping across the country this week will bring snow, ice and thunderstorms, forecasters said.

Winter Weather Advisory expanded for central Idaho mountains with heavy snow through Thursday. Wintry travel conditions above 4,000 feet with up to 20 inches possible in high elevations.

Winter Weather Highlights cover nearly all of western Montana as a potent system/cold front blow through overnight. Most valleys will see snow, but may not accumulate much along the 93 corridor.

Today you can expect moderate to heavy snow to develop over northwestern Montana, prompting a Winter Storm Warning and Winter Weather Advisories through Wednesday. Be cautious as gusty

Heavy snow, ice and freezing rain are all in the mix. Conditions could get messy later Sunday and into Monday morning's commute.

Heavy snow Tuesday through Thursday could lead to treacherous travel conditions in the Cascades and some areas of Eastern Oregon. Officials advise people to delay travel if possible.

A couple of fronts will move through Montana the next few days with areas of heavy snow and strong wind. While there will be some heavy snow showers and squalls in the lower elevations, the mountains of western Montana will once again pick up the lion's share of the snow.

Fresh weather warnings have been issued for snow and ice - with one danger to life flood warning requiring a large-scale evacuation.