Avalanche Forecast

Issued: Mar 30th, 2021 3:00PM

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

Avalanche Canada jcoulter, Avalanche Canada

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Expect spring sun and rising freezing levels to increase the hazard as the day progresses. Leave solar slopes before they get moist. Moderate wind could help keep things cool, but could also be building new wind slabs near ridge crests. 

Summary

Confidence

Moderate - Uncertainty is due to how the snowpack will react to the forecast weather. Uncertainty is due to the limited number of field observations.

Weather Forecast

TUESDAY NIGHT - Clear / moderate to strong north west wind / alpine low temperature near -10 / freezing level at valley bottom.

WEDNESDAY - Mostly clear / moderate to strong west wind / alpine high +2 /freezing level 2000 m

Stating Thursday through Easter weekend, models suggest it is possible we will not get good overnight recovery.

THURSDAY- Potential for no overnight freeze / partly cloudy / moderate south west wind / alpine high +3 / freezing level 2200 m

FRIDAY - Partly cloudy / moderate south west wind / alpine high of 0 / freezing level 2000 m

Avalanche Summary

There were no field observations on Tuesday, but neighbouring regions reported size 1-2.5 avalanches from Monday/Tuesday.

Natural avalanches up to size 2 were reported by our field team on Monday. On the east slope there were reports of storm slabs forming during the day that were reactive to ski cutting in the size 1.5 range. 

Snowpack Summary

The 20-40 cm of recent storm snow appears to be bonding well to previous melt freeze crusts from mid March that were found on all but steep north facing alpine slopes. Moderate northerly winds have been transporting snow and forming new wind slab in lee features. Cornices are reported to be large and looming. With rising freezing levels and sunny skies, snow will likely loose strength as it gets moist at lower elevations and upper elevations on solar aspects. 

The mid-pack is firm and well settled. Some faceted snow and a decomposing melt-freeze crust can be found near the base of the snowpack.

Terrain and Travel

  • Be alert to conditions that change with elevation and sun exposure.
  • Be especially cautious as you transition into wind affected terrain.
  • Extra caution for areas experiencing rapidly warming temperatures for the first time.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.
  • Closely monitor how the new snow is bonding to the old surface.

Problems

Loose Wet

An icon showing Loose Wet

Loose wet avalanches in steep southerly terrain should be on your radar with sunny skies and freezing levels rising to ridge top on Wednesday. A natural cycle is likely with spring sun hitting fresh storm snow for the first time.  

Leave slopes before they get moist and avoid overhead hazards like cornices and avalanche paths in the heat of the day.

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

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Wind Slabs

An icon showing Wind Slabs

Moderate to strong westerly winds have been loading lee terrain, especially near ridge crests. Also watch for stiffer wind slabs in more exposed, open terrain.

Sheltered terrain out of the wind will provide better quality riding.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Cornices

An icon showing Cornices

Recent strong southwest through northwest winds have been building fresh cornice growth. 

Cornices falls can be a hazard on their own, and can also act as a trigger for avalanches on the slopes below. 

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1.5 - 3

Valid until: Mar 31st, 2021 4:00PM