Avalanche Forecast

Issued: Apr 16th, 2022 4:00PM

The alpine rating is low, the treeline rating is low, and the below treeline rating is low. Known problems include Cornices.

Garth Lemke,

Cornice activity remains the main concern. Select your route to avoid exposure to them. They are large and foreboding. Monday night into Tuesday may bring less of an overnight freeze and warmer low elevation daytime temperatures hence be vigilant.   

Summary

Weather Forecast

Saturday night will be clouds, flurries, 4cm of snow, -11C, and light winds. Sunday will have sun and cloud, no new snow, -6C, 1400m freezing level, and light west winds. Monday will be clouds and flurries, a trace of new snow, -10 to -3C, 1800m freezing level, and light South winds. Flurries, 5cm of snow, and 1700m freezing levels on Tuesday.

Snowpack Summary

North winds have pressed surface snow and scoured exposed features TL and above. Isolated wind slabs and cross loaded pockets exist in the alpine but have bonded well to previous surface. On solar aspects a crust down 10-15cm exists up to 2400m in addition to a 1-5cm thick melt-freeze crust down 10cm on all aspects up to 2200m elevation.

Avalanche Summary

Saturday's patrol observed a few loose dry steep solar aspects alpine but nothing bigger than a size 1. Two natural cornice failures were noted on the Churchill range from Thursday and Tuesday and did not trigger slabs below. On Wednesday, a cornice triggered size 2 wind slab was noted on Pyramid and another off Manx peak near Marmot basin.

Confidence

Freezing levels are uncertain on Monday

Problems

Cornices

An icon showing Cornices

Cornice failures have been observed this past week. The activity is likely from a combination of strong spring solar input, new cornice growth and cold temperatures making them susceptible to failing. They are not triggering slopes below. 

  • Minimize exposure to corniced features.
  • Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Apr 17th, 2022 4:00PM