Snow being made at Loveland Ski Area. (Handout)

BILLINGS, Mont. — An early winter storm is forecast to bring the first heavy snowfall of the season to portions of the U.S. Rocky Mountains this week.

The National Weather Service on Monday issued winter storm warnings for large areas of Wyoming and southern Montana. The warnings were in effect through midday Wednesday.

Up to 2 feet of snow was expected in the Beartooth Mountains near Red Lodge, Montana with temperatures well below freezing.

Forecasters say the Sheridan, Wyoming area can expect up to 18 inches of snow.

Winter weather advisories were issued for portions of Colorado, Idaho, Nevada and Utah.

The Colorado Department of Transportation warned motorists traveling in the Western Slope mountains starting Monday night to prepare for snow packed and icy conditions and difficult travel conditions due to falling and blowing snow up to 60 mph through Tuesday, especially in mountain areas west of Denver including Interstate 70.

The highway department said a second system will hit the northern and central mountains bringing frigid temperatures Thursday into Friday. Strong, gusting winds are expected on the Front Range and Eastern Plains.

Loveland Ski Area, Arapahoe Basin and Keystone Resort all recently began making snow in preparation for their opening days. The resorts often open before the end of October.

The Associated Press