Avalanche Forecast

Issued: Jan 2nd, 2019 3:32PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is moderate. Known problems include Storm Slabs.

Avalanche Canada shorton, Avalanche Canada

Danger will increase throughout the day on Thursday as an intense storm builds fresh storm slabs.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain on Thursday

Weather Forecast

WEDNESDAY NIGHT: 5-10 cm of snow, wind increasing from moderate to strong from the southwest, alpine temperatures drop to -6 C. THURSDAY: 15-20 cm of snow, strong wind from the southwest, freezing level climbing to 1200 m, alpine high temperatures around -2 C.FRIDAY: Another 10-20 cm of snow, strong wind from the southwest, freezing level around 1200 m, alpine high temperatures around -3 C.SATURDAY: Mostly cloudy, light wind, alpine high temperatures around -5 C.

Avalanche Summary

No new avalanches were reported on Tuesday, while ski cutting produced a few small wind slab avalanches (size 1) on freshly loaded slopes on Monday. Looking ahead, a widespread storm slab problem will develop with the incoming storm. The additional weight of the new snow may also stress deeper weak layers.

Snowpack Summary

Fresh storm slabs will form as a storm passes through the region on Thursday and into Friday. Several layers of small spotty surface hoar and thin crusts have been observed in the top 50 cm of the snowpack. Some snowpack tests suggest the snow may be poorly bonded to these layers in isolated areas. However, the main weak layer worth considering is still the widespread weak layer that formed in early December. The layer consists of a rain crust with a weak layer of feathery surface hoar and sugary facets and can be found 50 to 100 cm below the surface. Although there has not been a reported avalanche on this layer in over a week, the incoming storm could be enough to reawaken it.

Problems

Storm Slabs

An icon showing Storm Slabs
Heavy snowfall and strong wind will build fresh storm slabs on Thursday, with the greatest danger on steep and wind loaded slopes.
Minimize exposure during periods of heavy loading from new snow and wind.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.If triggered the storm slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Jan 3rd, 2019 2:00PM