BOISE COUNTY -- The warm weather has forced the Idaho Transportation to close a 12-mile stretch of Idaho 21 between between the Grandjean Junction and Banner Summit. The road was closed at noon today.
Officials say the warm temperatures will bring rapid melting and instability to the existing snowpack, which received 29 inches of new snow in the past five days.
There have been two previous closures on the section of highway known as Avalanche Alley. During those closures there were 60 slides, and half of them reach the highway.
During the latest closure about a week ago, there were 25 slides, and nine of them reached the highway. Two of the avalanches were quite large, up to 40 feet deep and several hundred feet wide. Tons of timber and debris also reached the highway.
Before heading out, check the latest road reports on our website.