Avalanche Forecast
Issued: Feb 26th, 2019 4:16PM
The alpine rating is Wind Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeFresh wind slabs are sitting on top of buried wind slabs that are sitting on facets (weak, sugary snow). The fresh wind slabs are touchy and the buried wind slabs may remain reactive to human triggers longer than is typical for this region.
Summary
Confidence
High - The weather pattern is stable
Weather Forecast
TUESDAY NIGHT: Clear / Light, northeasterly winds / Alpine low -13.WEDNESDAY: Sunny / Light, northeasterly winds / Alpine high -5.THURSDAY: Mix of sun and cloud / Light, northerly winds / Alpine high -6.FRIDAY: Sunny / Light, northwesterly winds / Alpine high -12.
Avalanche Summary
On Monday, there were numerous natural and human triggered wind slab avalanches up to size 2 reported on primarily south and east aspects at treeline and above.Several size 2, explosive triggered, persistent slab avalanches were reported in low elevation cut blocks south of Revelstoke on Saturday. Persistent slab avalanche activity on the mid-January weak layer has slowed down but not stopped, with human triggered avalanches on this layer being reported on a regular basis. Check out the great photos from a recent MIN. Take note of the low angle terrain and the light load of a single ski track that triggered this avalanche.
Snowpack Summary
Strong northeasterly ridge-top winds on Monday created fresh wind slabs on lee features at treeline and above. Additionally, there are buried wind slabs on a variety of aspects that are sitting on facets (sugary snow) which may cause them to remain reactive to human triggers longer than what is typical for a wind slab problem in this region.Two additional weak layers of surface hoar have produced large avalanches in the region over the past month. A layer buried at the end of January is around 40 cm deep and a layer buried mid-January is between 60 and 90 cm deep. The mid-January layer may also be associated with a crust on southerly aspects. These layers are most prominent at treeline and below treeline elevations. The remainder of the snowpack is generally considered to be strong in most areas. However, isolated failures have occurred near the base of the snowpack in this region, or in neighboring regions, resulting in large, destructive avalanches. These avalanches have primarily been in steep, rocky, high alpine areas with a shallow snowpack.
Problems
Wind Slabs
Fresh wind slabs are sitting on top of buried wind slabs that are sitting on facets (weak, sugary snow). The fresh wind slabs are touchy and the buried wind slabs may remain reactive to human triggers longer than is typical for this region.
Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Steep and rocky terrain are likely places to trigger buried wind slabs.Avoid slopes that sound hollow or drum-like.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
It is becoming less likely, but still possible to trigger an avalanche on one of the surface hoar or crust layers buried 30 to 80 cm deep. These layers have created a low likelihood, high consequence scenario.
Avoid steep, open and/or sparsely treed slopes at and below treeline.Avoid low elevation cut-blocks where this layer is well preserved.Use conservative route selection; choose moderate angled terrain with low consequence.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Valid until: Feb 27th, 2019 2:00PM