Avalanche Forecast

Moderate - Uncertainty is due to how the snowpack will react to the forecast weather.

The region now sits under a warm ridge of high pressure which is expected to persist through the week bringing very high freezing levels and sun. 

Sunday night: Partly cloudy, light NW wind, freezing levels around 2400 m with an inversion.

Monday: Sunny, light NW wind, freezing levels dropping to 1200 m. 

Tuesday: A mix of sun and cloud, moderate NW wind, freezing levels around 2500 m with an inversion. 

Wednesday: Sunny, light NW wind, freezing levels around 2500 m with an inversion.

Avalanche activity associated with the warming over the weekend has been minimal. But with sustained warm temperatures and sun forecast through the week, we remain wary. Parts of the region are currently under a Special Public Avalanche Warning (SPAW). Check out this new blog post for additional information.

On Saturday a size 3 glide slab was observed at 2200 m in the north of the region. On Wednesday, a size 1.5 glide slab was observed at 1400 m in the Coquihalla area. Glide slabs are difficult to forecast but they are often a product of sustained warm weather, as melting snow lubricates between the ground and the snowpack.

Over the weekend, evidence of natural wind slabs size 1.5-2.5 were observed in the south of the region, suspected to have run at the end of last week.

At upper elevations, moist surfaces or a thin crust can be found on solar aspects, while soft dry snow may still be found on shady aspects in wind-sheltered areas. Wind slabs linger in exposed high elevation terrain, mainly on north and east aspects. Below 2100m, the widespread January 16 melt-freeze crust sits below 15-30 cm of recent snow. In the south of the region, this crust is one of many in the upper snowpack. There have also been reports of a layer of small surface hoar above the Jan 16 crust in the north of the region on polar aspects at treeline and in the alpine but this does not seem to be widespread. At lower elevations, the upper snowpack is moist or wet and may be capped with a breakable crust.

The early December crust/facet layer is now typically down 100-150 cm but may be as shallow as 60 cm and as deep as 200 cm with lots of variability through the region. The layer is most prominent between 1700 and 2100 m. The crust appears to be breaking down in the south of the region but remains a concern in the north. The layer continues to be a concern through the current period of major warming and sun. The most likely place to trigger it would be in thin, rocky snowpack areas where it is shallowest.

• Cornices become weak with daytime heating or solar exposure.
• Minimize exposure to steep, sun exposed slopes, especially when the solar radiation is strong.
• A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
• Avalanche hazard may have improved, but be mindful that deep instabilities are still present.