Recent storm snow accompanied by strong wind has formed storm slabs that may be reactive and easily triggered by the weight of a skier or rider. These may be extra sensitive in wind-loaded areas at upper elevations.
Fresh and reactive storm slabs are likely to be encountered, especially in wind-loaded areas at upper elevations. A change in wind direction means that wind loading may be found on many aspects.
Keep in mind that brief periods of sun can initiate natural avalanches, especially in areas that saw high snowfall amounts.
Another Pacific frontal system is due to arrive Wednesday bringing snow at upper elevations and strong wind.
Tuesday: A mix of sun and cloud. Ridgetop wind strong from the northwest. Freezing levels 400 m.
Wednesday: Mix of sun and cloud. Ridgetop wind strong from the southwest. Alpine temperatures near -6 and freezing levels 1000 m.
Thursday: A mix of sun and cloud with light snow amounts. Ridgetop wind light from the southwest and freezing levels 900 m.
There are no recent reports of avalanche activity.
Avalanche size and sensitivity are expected to decrease over the next few days, however, reactive storm slabs are still anticipated, especially in wind-loaded slopes at upper elevations. If the sun comes out on Tuesday, it could quickly trigger natural avalanches within the new snow.
Cornices are large at this time of year, and they become weaker when the sun hits them.
15-35 cm of snow has fallen in the region over the weekend. This was accompanied by strong southwest to northwest wind. Fresh wind slabs may exist on most slopes due to changing wind directions. At lower elevations, much of this precipitation fell as rain below treeline. The lower elevations are now showing a firm surface crust.
Buried 70-120 cm deep, a spotty layer of surface hoar may exist on sheltered north aspects, as well as a crust on south aspects and below 1450 m. Recent observations suggest that this interface is bonding.
The mid and lower snowpack is reported as well settled and strong in most areas. However, weak facets exist at the base of the snowpack in the more shallow snowpack zones within much of the region and have the potential to be triggered on steep, rocky slopes with a shallow or thin to thick snowpack; especially with large loads such as a cornice fall.
