Avalanche Forecast

Moderate - Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack. Uncertainty is due to the fact that persistent slabs are particularly difficult to forecast.

The first in a series of storm systems is forecast to reach the region on Sunday afternoon. 

Saturday Night: Mainly clear, moderate SW wind, treeline low around -12 °C. 

Sunday: Increasing cloud cover with light snow in the afternoon up to 5 cm, moderate SW wind, treeline high around -4 °C. 

Sunday night: Snowfall 10-20 cm, moderate SW wind, treeline low around -5 °C.

Monday: Snowfall 15-30 cm, moderate to strong SW wind, treeline high around -1 °C.

Monday night and Tuesday: Periods of heavy snowfall continuing overnight and then easing during the day, moderate to strong SW wind, freezing levels reaching near 2000 m. 

No new avalanches were reported on Thursday or Friday. On Wednesday, skiers were triggering small wind slabs. The Avalanche Canada field team reported whumpfing and cracking in places where the late-January surface hoar is still preserved and reactive, but they didn't see any new avalanches.

Last Saturday, there was a machine-triggered persistent slab avalanche on a surface hoar layer in an open gully feature in the Rolling Hills area.

10-30 cm of old storm snow has been redistributed by recent variable winds earlier in the week which has formed thin wind slabs. Reports from Saturday suggest wind transport continues but wind slabs are expected to be relatively small and isolated. In south-facing terrain, the recent snow sits on top of melt-freeze crusts, and in exposed terrain, the recent snow sits over firm, wind-affected surfaces.

A buried surface hoar layer may be found 30-60 cm deep on sheltered, north-facing treeline-type features. This distribution of this layer is spotty in nature but has recently produced avalanches, whumpfing, and snowpack test results in the Flathead. While it does not appear to be as widespread or reactive in the Lizard, it has been found in some locations. 

The lower snowpack is well consolidated, with a crust/facet layer from early-December found near the bottom of the snowpack. It is currently considered dormant but could become active later this season. Check out the forecaster blog for more information. 

• Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
• Be aware of the potential for large avalanches due to the presence of buried persistent weak layers.
• Shooting cracks, whumphs and recent avalanches are strong indicators of an unstable snowpack.