Northern San Juan

Avalanche

Jeff Davis Ann Mellick · Feb 11, 2021 · Northern San Juan

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Weather

Westerly winds, mostly sunny skies, and mild temperatures. It was chilly when traveling in the wind, but warm out of the wind and at pass level.

Snowpack

Moderate to strong southwest and northwest winds drifted Wednesday's snow onto leeward slopes. Snow looked to be drifting further down the slope and remained soft. Bottom line... On most slopes multiple persistent weak layers sit below a slab. The difference between slopes is the depth of the weak layers and firmness of the slabs above. Though it has been a few days since our last report of avalanche activity, slopes still have a weak structure. Digging on a northeast facing slope above treeline three weak-layers were observed. A pencil hard wind slab dominates the middle of the snowpack. Avalanches in the surface snow could step down, triggering larger avalanches. If avalanches start to step into the largest facet layer below the pencil hard slab we can expect to see some Very Large (Destructive size 3) avalanches running full path.

Avalanche

Small sluffs triggered by wind-loading observed today- all on lees slopes in the alpine.