The National Weather Service has issued a winter storm warning for northern Blaine County and western Custer County, including the cities of Ketchum, Sun Valley and Stanley.
The warning is in effect from 11 a.m. Monday, Jan. 3, through 5 a..m Tuesday, Jan. 4.
The forecast calls for heavy snowfall, strong wind gusts and snow accumulations of 3-8 inches at lower elevations and upwards of 12 inches at mountain passes and higher elevations.
"Winds gusting as high as 45 mph will create blowing and drifting snow. Plan on difficult driving conditions. Gusty winds will create low visibility and blowing and drifting snow," the Weather Service stated.
The Sawtooth Avalanche Center considered avalanche danger in the Wood River Valley and surrounding mountains was considered "moderate" on Monday.
"Triggering an avalanche is possible in wind-affected terrain—look for evidence of wind such as drifts, stiffened surfaces, or cornices," the Center stated. "In these areas, you could trigger a relatively small wind drift, or a very large and destructive avalanche breaking on deeper weak layers near the ground. Safer conditions can be found on wind-sheltered slopes."