Avalanche Forecast

Issued: Nov 26th, 2019 8:09AM

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

Parks Canada ross campbell, Parks Canada

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Early season conditions are still in effect. Buried rocks, alder and stumps could ruin your season. Days are short, give yourself plenty of time to get back to the parking lot.

Summary

Weather Forecast

An Arctic high pressure moves over Rogers Pass, bringing with it cold and clear air. There is a chance of convective flurries and moderate winds from the NE though today. No significant accumulated precipitation is in the long term forecast. The only notable weather event that is forecasted, will be cold Northerly winds this week.

Snowpack Summary

The weekend's 40cm of storm snow was accompanied by mod-strong S'ly winds, which have built fresh storm slabs. These slabs overlay either 5-10mm surface hoar at treeline and below, or a crust, which is widespread below 1600m and on steep solar aspects. Persistent slabs exist down 60-90 cm and may be triggered by larger loads.

Avalanche Summary

Sunday's storm produced a decent natural avalanche cycle to size 3 in Rogers Pass over the weekend. These avalanches traveled through brush-filled terrain below treeline, into valley bottoms. Avalanche activity has tapered off since the storm; with only one report of a skier triggered avalanche yesterday on Glacier Crest.

Confidence

Due to the number of field observations

Problems

Storm Slabs

An icon showing Storm Slabs

40cm of new snow fell over the weekend accompanied by strong winds, creating storm slabs that buried the November 22nd Surface Hoar.

  • Use caution in alpine and open treeline lees. Recent snowfall has created storm slabs.
  • Minimize exposure to terrain traps where the consequences of an avalanche could be serious.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Persistent Slabs

An icon showing Persistent Slabs

The persistent slab is down 60-90cm and sits atop a crust/surface hoar/stellar layer.

  • If triggered the storm slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Nov 27th, 2019 8:00AM