"CONTINUED HIGH AVALANCHE HAZARD"
Avoid all avalanche terrain. A storm pushing through Tuesday night and Wednesday morning will bring heavy snow and strong winds, which will overload the snowpack.
With a further 25cm on the way, and very strong winds, fresh wind slabs will grow. Avalanche activity is expected. Lower elevations may also be an issue if the recently buried rain crust becomes a sliding layer.
Avalanches initiated in the surface wind slab could trigger this deeper instability. Large and destructive avalanches are possible.
Rapid loading from the incoming storm will lead to widespread sluffing.
A natural avalanche cycle continues with slab avalanches up to size 3 in Alpine and Treeline terrain. These slabs are anywhere between 20 and 100cm thick, including many that are stepping down to the Nov crust layer. Explosives control work on EEOR today also produced several size 2 avalanches. With the incoming storm Tuesday night and Wednesday morning, a natural avalanche cycle is expected to continue.
Incoming new snow and strong winds will add to existing wind slabs at Treeline and above. There is already a 25-40cm thick surface wind slab, and this will grow. Unfortunately, this is sitting on a softer layer of decomposed particles that is very reactive to field tests. If this layer is triggered, there is a strong likelihood that it will step down to the November crust (now buried 90-120cm), creating large avalanches. At 2200m and below the incoming snow will land on a rain/temperature crust from the last few days. The bond at this interface will be important to watch, as the crust could form a good sliding layer.
Wednesday is expected to be overcast and snowy. Total accumulations should be in the neighbourhood of 25cm. With the passing of a cold front, the winds will be strong from the SW switching to the NW, and temperatures will drop from -4C in the morning to -12C in the evening.
More details can be found in the Mountain Weather Forecast.
