UP avalanche ?

[snoluver1]

John,
Do you know if there has ever been a reported case of an avalanche anywhere in the UP?
I would think it is possable, given the snow load you can get up there, and I know there are certainly slopes between 30 and 50 degrees. Most of them are covered heavily with trees, but what about open hills. I know most of the snow is lake effect, but maybe spring storm with wet heavy stuff on top of setteled lake effect which could have developed surface hoar??

 

[frnash]

I saw a few last year — snow slidin' off John's roof, in the Journal! I think that's as close as it gets in da UP!

 

[admin]

Too many trees is the main problem. I do not know of any hills large enough to slide that are not covered in trees. I do know plenty of hills that could be prime candidates for slides if they were bare.

Our climate does not produce much surface hoar like the higher terrain out west. Lots of clouds at night to keep the radiation balance more in check. Freezing rain would be our best bet at creating a weak layer. Plus, a wet and heavy snow would bond well with the existing snowpack, so the only way it might lead to an avalanche would be to top load a snowpack with a buried weak layer.

There was an avalanche on one of the ski slopes at Mt. Ripley. It was human enhanced though. The first year that the hill had snow making equipment, they tried to fill a natural concave in the terrain with snow so that it could be groomed. They put most (or all) of their snow guns in that natural concave and let them make snow all night. Early in the morning, the hill became overloaded with snow and broke loose. It was actually a pretty respectable slide, being about 30" deep and hundred yards wide or so and slid for a few hundred yards. Plenty enough to bury someone.

-John