Avalanche Forecast

Issued: Apr 13th, 2018 4:41PM

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

jsmith, Avalanche Canada

Northwest Inland.

Recent snow and wind have formed small wind slabs on lee features below ridgetops.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

SATURDAY: Cloudy with isolated flurries. Moderate southwesterly ridgetop winds. Alpine temperature -4. Freezing level around 1000 m.SUNDAY: Mostly cloudy. Light northeasterly ridgetop winds. Alpine temperature -4. Freezing level rising to around 1200 m.MONDAY: Mostly sunny. Light northeasterly ridgetop winds. Alpine temperature -6. Freezing level around 900 m.

Avalanche Summary

No new avalanches were reported in this region on Thursday. On Wednesday, a size 2 wind slab and a 2.5 deep persistent slab both on west aspects between 1000-1300 m were triggered by explosives near Ningunsaw.

Snowpack Summary

5-10 cm of recent storm snow and strong southeasterly winds have formed fresh wind slabs on lee features at treeline and above.Weak layers buried around March 19th are roughly 40 cm below the surface (up to 100 cm in deeper snowpack areas). These weak layers include surface hoar on shaded aspects at high elevations and hard crust layers on solar aspects and below treeline.Near the bottom of the snowpack, weak and sugary facets are found in shallow, rocky snowpack areas. Storm slabs have stepped down to these facets and produced very large avalanches in the far northern parts of the region.

Problems

Wind Slabs

Recent snow and strong winds have formed thin wind slabs in leeward areas near ridge crests and convex features. These slabs may be touchy were they sit on a recent crust.

Use caution when transitioning into wind effected terrain.Avoid areas that look freshly loaded with snow; especially convex features below ridgetops.Avoid shallow, rocky areas where the snowpack transition from thin to thick.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 1.5

Loose Wet

When the sun comes out it will quickly weaken the new snow and cause loose wet avalanching on steep solar slopes.

Watch for signs that the snow is heating up such as pin-wheeling or the surface snow becoming moist.Avoid steep terrain that is in the sunshine.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Apr 14th, 2018 2:00PM