Avalanche Forecast

High

FRIDAY: 10cm new snow through the day, moderate to strong southerly winds, freezing level rising to between 1800 to 1500m. SATURDAY: up to 20cm overnight with lingering flurries through the day, moderate westerly winds, freezing level of around 1300m. SUNDAY: flurries, light westerly winds, freezing level returning to valley floor overnight before rising to 1500m through the day.

A size 3 natural avalanche that failed on surface hoar earlier in the week at treeline near Blue River was reported to be around 1500m wide, demonstrating the ability of this layer to propagate and produce large destructive avalanches. On Sunday, a helicopter is believed to have remotely triggered a size 2.5 persistent slab avalanche at the 1900m elevation from a distance of 200m. The slab was about 400m wide, 90cm deep and is thought to have failed on the early January surface hoar. Although both of these avalanches occurred on the east side of Highway 5 (technically in the Northern Monashees), similar touchy conditions likely exist in many parts of the Cariboos.

Up to 15cm of new snow fell overnight on Wednesday adding to the 30-50cm that has fallen in the last week. Southwesterly winds on Thursday have formed fresh wind slabs in lee features at treeline and in the alpine. Bellow 1500m this new snow is sitting on a supportive crust. Several touchy layers of surface hoar from early to mid-January are now buried between 70 and 120cm and are variably reactive. In other words, some slopes are difficult to trigger while remote triggering is still possible on other features. These layers have the potential for wide propagations, and smaller avalanches could step-down to one of these layers. Snowpack depths are variable across the region and shallow snowpack areas may have weak facetted crystals near the ground.