Threats of potential avalanche activity stymied travel along a mountain route northeast of Boise for much of the long weekend.
A portion of Idaho 21, which connects to Boise near Lucky Peak Reservoir, closed early Saturday afternoon due to avalanche risk, according to a news release from the Idaho Transportation Department. It reopened at about 1 p.m. Monday, but ITD said avalanche risk in the area “is still considerable. “
The 12-mile section stretches from Grandjean Road north of Lowman to Banner Creek Summit, about 20 miles south of Stanley (milepost 93.75 to milepost 105.4).
The Sawtooth Avalanche Center deemed the risk of avalanche in the area “considerable” on Sunday — adding that avalanches in the Sawtooths are likely and, if they occur, would be large. The center reported that skiers near Banner Summit triggered an avalanche on Saturday.
Parts of Idaho 21 on either side of the closure were covered in slush, packed snow, patches of ice and dense fog, according to ITD’s road report. The department reported similar conditions on Idaho 75 past Stanley, warning drivers to use extreme caution due to risk of rock falls.
For updates on the Idaho 21 closure and other mountain roadways, visit ITD’s 511 map or download the 511 app.