Avalanche Forecast

Issued: Mar 19th, 2018 4:50PM

The alpine rating is low, the treeline rating is low, and the below treeline rating is low. Known problems include Wind Slabs.

Avalanche Canada ghelgeson, Avalanche Canada

It is a good time to be traveling in the mountains, but remember that low danger does not mean no danger. Loose wet avalanche activity should be limited Tuesday, but stubborn old wind slabs and large cornices demand our respect.

Summary

Confidence

High - Timing, track, or intensity of incoming weather system is uncertain on Thursday

Weather Forecast

Tuesday offers a bit of a drying trend for most of the province. A low approaching from the Gulf of Alaska may bring some precipitation to the region beginning Wednesday afternoon.TUESDAY: Broken cloud cover, freezing level beginning at 700 m rising to 1400 m, light westerly wind, trace of precipitation possible. WEDNESDAY: Overcast, freezing level beginning at 800 m rising to 1100 m, light south wind, 4 to 6 mm of precipitation expected.THURSDAY: Broken cloud cover with some clearing in the afternoon, freezing level holding around 700 m, light to moderate south/southwest wind, 5 to 8 mm of precipitation possible.

Avalanche Summary

A few skier triggered soft slabs size 1 to 1.5 were reported from west facing alpine terrain Sunday. These were likely running on the mid-March crust.Saturday's reported avalanche activity was limited to sluffing and snowballing in steep terrain. There was a rather anomalous size 3.5 that was seen on the Cheakamus Glacier from Whistler last Thursday.  We don't have details on the failure plane of this avalanche, but it may have run on the mid-February crust.

Snowpack Summary

A new crust exists on the surface on solar aspects at all elevations. High elevation polar aspects (those facing north and east) continue to hold dry snow, this is also where new surface hoar has been spotted on the surface.5 to 20 cm of wind distributed snow fell last week which came to rest on the mid-March crust on all but high elevation north aspects.50 to 100 cm below the surface is a combination of facets, surface hoar, and/or crust known as the mid-February layer. This interface has not been active recently, but it does continue to produce resistant planar results in snowpack tests. The mid and lower snowpack is strong and well settled.Variable winds in the past month have built up cornices on many ridgelines. They will become touchier as daily temperatures rise and when they are subject to the strong early spring sun on clear days.

Problems

Wind Slabs

An icon showing Wind Slabs
It is a good time to be traveling in the mountains. Increased cloud cover should put the brakes on loose wet activity. Use normal caution and be aware that small wind slabs near ridge crest may be sensitive to human triggering.
Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.Give cornices a wide berth while on or below ridges.Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Mar 20th, 2018 2:00PM