Avalanche Forecast

Issued: Jan 31st, 2019 8:02AM

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

Parks Canada andrew jones, Parks Canada

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Snow is once again in the forecast! Watch for slab development as we head towards a period of natural avalanches in the coming days.

Summary

Weather Forecast

A low pressure system is poised to stall over the area for the next 3 days delivering 10cm today, 10cm tonight, 22cm on Friday and 10cm on Sunday. For today, freezing levels climb to 1300m with and alpine high of -4 and SW winds 20km/h. Ridge winds will pick up this afternoon and gust to 50km/h with the arrival of a front.

Snowpack Summary

10cm of new snow overnight with moderate S winds. New snow sits atop hard wind slabs in the alpine and exposed areas at treeline. The January 17 surface hoar is buried 30-50cm and is most reactive between 1400-1900m, and where it overlies a crust on steep solar aspects. A reloaded crust from November has been reactive on steep south aspects.

Avalanche Summary

No new avalanche activity observed in the HWY corridor yesterday. On Tuesday there was a skier accidental size 2.5, on a steep, rocky, unsupported, South facing slope. 2 involved, 1 partial and 1 full burial, see MIN.

Confidence

Intensity of incoming weather systems is uncertain

Problems

Loose Dry

An icon showing Loose Dry
Snow is forecasted for the next several days. Expect new snow to bond poorly causing loose avalanches in steep terrain. This problem will transition into a storm slab as snowfall amounts build up over the next 24hrs. Winds will increase snow loading.
Be cautious of sluffing in steep terrain, particularly where the debris flows into terrain traps.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 1.5

Persistent Slabs

An icon showing Persistent Slabs
The Jan 17th Surface Hoar layer is now down 30-50cm. This layer exists on all aspects, and is most problematic between 1400-1900m and on steep solar aspects where it overlies a crust.
Use caution on open slopes and convex rolls where buried surface hoar may be preserved.Convex features and steep unsupported slopes will be most prone to triggering.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Feb 1st, 2019 8:00AM