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Weather Wise: Wind impacts snowpack

Weather Wise: Wind impacts snowpack
Posted at 5:44 PM, Feb 14, 2022
and last updated 2022-02-14 19:44:55-05

HELENA — Last week's wicked wind interacted with Montana's mountain snowpack, pushing snow around and piling it up in other areas.

A tremendous amount of drifting occurred. The wind was strong enough and lasted long enough to completely blow off the snow atop 9,415-foot red mountain in the Scapegoat Wilderness.

Now the snow does not blow away and disappear. The windward slopes, or slopes facing the wind, can be bare. The leeward slopes face away from the wind, and this is where the snow gets transported to. Where the snow has settled on the leeward side, snow depth could be as deep as 30 to 40 feet. It's these areas where snow lasts well into spring and even summer.

Right along the Continental Divide, the west side of the divide saw wind transport most of this snow to just over the crest. Huge piles of snow and drifts have developed on the east side. Wind also compounds the snow making it rock hard. Monster cornices build up in these conditions, poised to fall in the warmer months of late spring and early summer.

Currently, in the mountains, the snow surface is wind buffed and firm. This layer will need to be watched as new snow this week will not bond well. Thus, a new avalanche will likely begin and continue to be active over the next several days. Last week's wicked wind is still affecting the state with lingering problems and issues.