Avalanche Forecast
Issued: Mar 29th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs, Loose Wet and Cornices.
swerner,
Avalanche Canada
Storm slabs at higher elevations may be reactive on Tuesday, especially in wind-loaded areas.
If the sun pokes through the clouds it can quickly initiate natural avalanches and weaken cornices.
Summary
Confidence
Weather Forecast
A ridge of high pressure will dominate for the next couple of days bringing cooler and dryer conditions. The Duffy will see stronger ridgetop wind than the Southern part of the region.
Tuesday: Mix of sun and cloud. Ridgetop wind moderate from the northwest. Alpine temperatures near -2 and freezing levels 1200 m.
Wednesday/ Thursday: Mix of sun and cloud. Ridgetop wind generally light with strong gusty periods from the southwest. Alpine temperatures near +1 and freezing levels 1800 m.
Avalanche Summary
A widespread natural avalanche cycle occurred on Sunday afternoon and evening up to size 2.5 during the storm. A near miss was also reported on the Coquihalla size 2.5. Check out this MIN report for more details.
A report from Mt. Rohr on Saturday showed a fresh cornice-triggered slab from a steep piece of terrain, a great reminder of cornice and associated avalanche hazards.
Looking forward, new snow from Sunday's storm may need a day or so to settle and form a good bond with the old surface. Extra caution should be taken in wind loaded areas, which may begin to include more south slopes as a forecast shift to north winds takes place.
Snowpack Summary
40-60 cm of new snow blanketed the region by Monday morning. This snow fell with strong southwest wind building fresh reactive storm and wind slabs. The new snow has buried a mix of widespread hard crust and a bit of moist new snow below about 1700 metres and to either sheltered low density or wind-affected dry snow above this elevation. The lower snowpack is strong and settled.
Cornices along ridgelines are large and looming, especially after this storm. Avoid slopes with cornices overhead and give them a large berth while travelling along ridgelines.
Terrain and Travel
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Problems
Storm Slabs
40-60 cm of fresh snow accompanied by strong wind have formed widespread storm slabs that are likely still easy to trigger, especially in wind-loaded areas.
With all of this new snow, even brief periods of sun can quickly trigger natural avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Wet
The spring sun can pack a punch quickly and initiate loose wet avalanches. Watch for signs of instability like natural avalanche activity, wet or moist snow surfaces, and snowballing, especially on solar aspects.
Aspects: East, South East, South, South West, West.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Cornices are large and looming along many ridgelines, and have likely grown with the recent snow and wind.
Aspects: North, North East, East, West, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Mar 30th, 2021 4:00PM
