Avalanche Bulletin - Sea to Sky

Avalanche Bulletin - Sea to Sky

Date Issued:

Valid Until:

Forecaster:JSmith

 

Large cornice failures are more likely during periods of warm weather.

 Use caution when traveling on corniced ridgetops and limit your exposure to slopes with large cornices overhead.

Sun, 24 AprMon, 25 AprTue, 26 Apr
Alpine2 Moderate2 Moderate1 Low
Treeline1 Low1 Low1 Low
Below Treeline1 Low1 Low1 Low
Confidence: Moderate
  • Uncertainty is due to the limited number of field observations.

Travel and Terrain Advice

  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.
  • Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
  • Back off slopes as the surface becomes moist or wet with rising temperatures.
  • Avoid exposure to steep sun exposed slopes.

Cornice

Cornices may be weak and reactive to human triggers. They create a significant falling hazard, and can produce large slab avalanches as they fall onto the slope below.  

Cornice failures are more likely during hot and sunny weather.

Wind Slab

Lingering wind slabs may remain reactive on lee features in the alpine.

 Use ridges or ribs to avoid areas of wind loaded snow. 

Forecast Details

Avalanche Summary

Numerous naturally triggered wet loose avalanches up to size 2 were reported on steep solar aspects in the alpine on Saturday. Some of the wet loose avalanches triggered small (size 1-1.5) wet slabs.

We currently have very limited avalanche observation data from this region.

Please consider posting your observations to the Mountain Information Network (MIN). Photos of current conditions and avalanches are the most helpful. 

Snowpack Summary

Lingering wind slabs may remain reactive on isolated, steep slopes in the alpine.

The recent snow is sitting on a variety of hard snow surfaces, including crusts and wind scoured snow. 

Below this, there are several crusts in the upper snowpack. In areas where there are weak facets sitting on top of the crusts, there is potential for large natural slab avalanches when freezing levels reach mountain tops for multiple days.

Avoid large slopes and avalanche paths during periods of intense warming.

Cornices are very large and more prone to failure during periods of intense warming.

Weather Forecast

Saturday night: Partly cloudy / Moderate southwest wind / Low of -4 / Freezing level 1500 m.

Sunday: Sunny in the morning, then increasing cloud throughout the day and 10-20 cm snow overnight ( rain below around 1300 m) / Moderate south wind / High of 4 / Freezing level 1800 m.

Monday: Mostly cloudy with isolated flurries/showers; 0-5 cm / Moderate south wind / High of 2 / Freezing level 1600 m.

Tuesday: Mix of sun and cloud with isolated flurries/showers; 0-5 cm / Light southwest wind / High of 0 / Freezing level 1400 m.

Source: avalanche.ca

Avalanche Bulletin - Sea to Sky