Avalanche Forecast
Issued: Feb 2nd, 2018 6:21PM
The alpine rating is Storm Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Low - Forecast snowfall amounts are uncertain on Saturday
Weather Forecast
Saturday: 5-20cm of snow possible Friday overnight into Saturday with another 5 to 30 cm potentially during the day / Moderate west winds / Freezing level around 1400mSunday: 5-20cm of new snow / Light southwest winds / Freezing level at 1000mMonday: 5-15cm of new snow / Moderate westerly winds / Freezing level at 1400mNote: Confidence is low for forecast wind values and precipitation amounts on Saturday and Sunday.
Avalanche Summary
On Friday, natural and human triggered storm slab avalanches were reported, especially in areas which saw locally intense snowfall amounts in the afternoon. Looking forward, expect newly formed wind slabs and the persistent slabs beneath them to remain reactive to human triggers with the potential for very large and destructive avalanches.
Snowpack Summary
Storm snow totals over the past two days are approximately 15-25cm, which fell with light to moderate winds from the south west.On Monday precipitation fell as rain below about 1300 metres and a near-surface crust may exist in some areas below treeline. Where more recent precipitation fell as snow, southwest winds may have formed touchy wind slabs in high elevation lee terrain.The critical instabilities, however, are buried well below the surface. See this video for a summary of conditions near Nelson. A mixture of weak surface hoar and/or a crust from mid-January is buried beneath all the storm snow at 80-110cm deep. Numerous recent avalanches to size 2.5 have been reported on this layer and large, destructive avalanches at this interface remain a concern.Below this layer lies a second crust/surface hoar interface buried early-January that is now 110-130 cm deep. Several recent avalanches have stepped down to this layer.The mid-December surface hoar layer is buried 120-150 cm below the surface. This layer has continued to produce step down releases and "sudden" test results. It is most pronounced at tree line, but is also present below tree line .
Problems
Storm Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 3rd, 2018 2:00PM