Avalanche Forecast

Issued: Apr 14th, 2018 5:30PM

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

jsmith, Avalanche Canada

Northwest Inland.

Rising temperatures and the chance for a bit of sunshine on Sunday may be enough to trigger loose wet avalanches on steep slopes facing the sun.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

SUNDAY: Mix of sun and cloud. Light northeasterly ridgetop winds. Alpine temperature -3. Freezing level rising to around 1400 m.MONDAY: Mix of sun and cloud. Light northeasterly ridgetop winds. Alpine temperature -5. Freezing level around 1100 m.TUESDAY: Mix of sun and cloud. Light southwesterly ridgetop winds. Alpine temperature -4. Freezing level around 1200 m.

Avalanche Summary

No new avalanches were reported in this region on Friday. 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

10-15 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

Loose Wet

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

Minimize exposure to sun exposed slopes when the solar radiation is strong.Watch for signs that the snow is heating up such as pin-wheeling or the surface snow becoming moist.Cornices become weak with daytime heating. Give them a wide berth both from above and below.

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Wind Slabs

Recent snow and strong winds have formed thin wind slabs in leeward areas near ridge crests and convex features. These slabs may still be reactive in isolated locations.

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

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 1.5

Valid until: Apr 15th, 2018 2:00PM