Avalanche Forecast

Issued: Mar 2nd, 2018 4:35PM

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

ghelgeson, Avalanche Canada

South Coast.

Clear skies combined with the strong late-winter sun will likely initiate natural avalanche activity. Avoid being on or underneath steep sun exposed slopes. South facing features may be particularly problematic due to a buried sun crust.

Summary

Confidence

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

Weather Forecast

We are moving into a high and dry period for the foreseeable future. Northwest flow across the province will allow a couple of shortwave troughs to ripple along the upper flow giving a mix of sun and cloud. At this time, precipitation amounts will be insignificant.SATURDAY: A few clouds, freezing level rising to around 1000 m, very light variable wind, no precipitation expected.SUNDAY: Scattered cloud cover, freezing level rising to around 800 m, light west wind, no precipitation expected.MONDAY: Scattered cloud cover in the morning, cloud building throughout the day, freezing level rising to around 800 m, light westerly wind, no precipitation expected.

Avalanche Summary

No new activity reported Wednesday or Thursday, but we suspect that a small natural storm slab avalanche cycle occurred. On Tuesday storm slab avalanches up to 15 cm in depth were very touchy and sensitive to ski cutting, check out these two MIN reports here and here.

Snowpack Summary

The region picked up 20 to 40 cm of snow Wednesday and Thursday with moderate winds out of the east/southeast. This adds to the 50 to 70 cm that fell between Saturday and Tuesday. All of this snow rests on previously wind-affected surfaces and a sun crust on southerly aspects.A hard rain crust that extends into alpine terrain is buried about 60 to 120 cm deep. There are no substantial weak layers below the crust.Cornices have formed on many alpine ridgelines. They will become touchier as they grow in size, as temperatures rise, and as they are subject to the strong late-winter sun on clear days.

Problems

Storm Slabs

20 to 40 cm of snow fell Wednesday and Thursday with moderate east/southeast wind, watch for wind and storm slabs in unusual locations. The forecast calls for clear skies, and the strong late winter sun is likely to initiate natural avalanches.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.Caution with south facing slopes, the sun will likely induce natural storm slab avalanche failure.Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Cornices

Large cornices have formed along many ridgelines. Cornices are inherently unstable, unpredictable, and demand respect, especially when the sun is out.

Firm cornices may pull back into flat terrain at ridgetop if they fail.Give cornices a wide berth when traveling on or below ridges.Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.

Aspects: North, North East, East, South East, South, South West.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Mar 3rd, 2018 2:00PM