Rain causes urban snow slides; danger is subsiding

Jumbled snow at the bottom of Behrends avalanche path on Tuesday. Photo courtesy of Pat Costello.

Jumbled snow at the bottom of Behrends avalanche path on Tuesday. Photo courtesy of Pat Costello.

The rain atop Juneau’s snowpack earlier this week caused a number of avalanches in the mountains around downtown.

CBJ avalanche forecaster Tom Mattice reports widespread natural snow slides on Tuesday above Thane Road, the Behrends Avenue avalanche path and other urban paths.

While some slide activity persists in isolated areas, he says the rain is now creating drainage channels in the snowpack.

“And once it develops full-depth drainage channels in the snowpack, instead of feeling the whole weight of the new rain on the snow a lot of it just drains through the snowpack,” Mattice says. “So the snowpack has a chance to settle and it becomes a little bit healthier.”

Thursday’s avalanche danger is considered moderate to considerable and natural avalanches are still possible.

We’re still in a bit of weakness  with above freezing temperatures and continued precip, so we still have the possibility for natural avalanches to occur.  But in many of those places, a lot of the snow has already slid off,” Mattice says. 

He says until temperatures drop to below freezing, avalanche danger will linger in places.