Avalanche Forecast

FRIDAY NIGHT: Cloudy skies with some isolated flurries bringing trace amounts of snow, moderate wind from the west, treeline temperatures around -5 C.

SATURDAY: Cloudy with flurries throughout the day bringing 10-20 cm of snow to the western Purcells and 5-10 cm along the eastern Purcells, strong wind from the southwest, treeline temperatures around -5 C.

SUNDAY: Mostly cloudy with scattered flurries bringing 5-20 cm of snow, light wind from the northwest, treeline temperatures drop to -10 C throughout the day.

MONDAY: Mix of sun and cloud, light wind from the northeast, treeline temperatures around -16 C.

While no significant human triggered avalanches have been reported over the past week, the incoming storm will likely form reactive wind slabs at upper elevations.

We have seen limited recent avalanche activity on the late January surface hoar layer, with the most recent report being a cornice triggered size 2.5 slab west of Forster Creek last Sunday (Feb 13). This avalanche occurred on north aspect at 2250 m. There is uncertainty about whether this problem will become more reactive with the incoming storm or whether it will remain unreactive.

New snow will form some isolated wind slabs at upper elevations and bring 5 to 20 cm of low density snow in sheltered terrain. Roughly 5 to 15 cm of snow sits above hard wind-affect snow and melt-freeze crusts in most terrain, except north-facing terrain at treeline where there may still be soft snow. North-facing treeline terrain also has a 20 to 40 cm deep surface hoar layer that was buried at the end of January. This layer has produced variable results in recent snowpack tests, and may still be reactive on some steep convexities. The lower snowpack is well consolidated, with a crust/facet layer found 80 to 150 cm deep. This layer is currently considered dormant, but could become active later this season as discussed in this forecaster blog.

• Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
• Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
• Use ridges or ribs to avoid areas of wind loaded snow.