Avalanche Forecast

Issued: Apr 18th, 2018 4:43PM

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

jsmith, Avalanche Canada

Northwest Inland.

Forecast new snow and strong winds will form small wind slabs in leeward areas near ridge crests and on convex features which may be reactive to human triggers.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

THURSDAY: Snow; accumulation 5-10 cm. Moderate to strong southwest wind. Alpine temperature -2. Freezing level 1200 m. FRIDAY: Cloudy with flurries; accumulation 3-5 cm. Moderate south wind. Alpine temperature -2. Freezing level 1200 m.SATURDAY: Mix of sun and cloud with flurries. Light west wind. Alpine temperature -3. Freezing level 1100 m.

Avalanche Summary

No new avalanches were reported in this region on Tuesday. However, I would expect the incoming storm on Thursday to form fresh wind slabs reactive to human triggers in wind affected terrain at treeline and above.

Snowpack Summary

Forecast new snow and strong winds are expected to create touchy wind slabs in wind affected terrain 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 crusts on solar aspects and below treeline.Sugary facets may be found near the base of the snowpack in shallow, rocky snowpack areas on shady aspects.

Problems

Wind Slabs

Forecast new snow and strong winds are expected to create small wind slabs on lee features at treeline and above.

Use ridges or ribs to avoid pockets of wind loaded snow.Give cornices a wide berth when travelling on or below ridges.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Apr 19th, 2018 2:00PM