Avalanche Forecast

Issued: Feb 7th, 2016 8:17AM

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

Avalanche Canada pgoddard, Avalanche Canada

Skyrocketing temperatures make avalanche forecasters nervous. Deeply buried weak layers could wake up, creating very large avalanches.

Summary

Confidence

Moderate - Timing or intensity of solar radiation is uncertain on Monday

Weather Forecast

Bring out the flip flops! A strong ridge of high pressure is expected to bring mainly sunny skies (above valley cloud) with no precipitation for the next three days. A warm southerly flow causes the freezing level to rise as high as 3000 m by Tuesday. Alpine temperatures should be well above 0.For more details check out http://www.avalanche.ca/weather.

Avalanche Summary

A widespread cycle of size 1-2 avalanches was triggered naturally and by skiers and explosives on Saturday in response to new snow and very strong SW winds. During this cycle, only one persistent slab was reported. It was triggered by explosives near Revelstoke and failed on the early January layer. While the likelihood of triggering a persistent slab has gone down, the consequences remain high. Forecast warming may make the persistent slab easier to trigger again.

Snowpack Summary

Strong to extreme SW winds on Saturday created wind slabs and cornices in many areas. Wind slabs may be lingering lower in start zones than normal due to the high wind speed. In sheltered areas, 15-40 cm recent storm snow is settling, and in some places may still be reactive as a soft slab. A rain crust sits below this in parts of the Monashees. In the far south, a layer of surface hoar is buried about 50-80 cm down. Professionals are still monitoring the early January persistent weak layer, down 80-120 cm. During Saturday's avalanche cycle, there was only one reported persistent slab, triggered with explosives. Prior to that, more than a week has passed since the last report of a persistent slab. However, in specific locations, it still produces hard, sudden results in snowpack tests, and forecast warming could wake it up again.

Problems

Wind Slabs

An icon showing Wind Slabs
Very strong winds have created wind slabs and fragile cornices on a variety of slopes. These may be extra sensitive with warm temperatures and sunshine.
Choose well supported terrain without convexities.>Travel on ridges to avoid freshly wind loaded features.>Avoid steep, open slopes.>Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Persistent Slabs

An icon showing Persistent Slabs
A deeply buried weak layer can still be triggered in some places, creating very large avalanches. Forecast warming may increase the sensitivity of this problem over the next few days.
Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar. >Be cautious around steep open slopes and convex rolls at and below treeline where buried surface hoar may be preserved. >Minimize exposure to sun exposed slopes when the solar radiation is strong.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

3 - 5

Valid until: Feb 8th, 2016 2:00PM