Avalanche Forecast
Issued: Apr 5th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Loose Wet, Storm Slabs and Cornices.
swerner,
Avalanche Canada
Start and finish your day early. Warm temperature and sunshine will increase the likelihood of avalanche activity, especially on steep slopes that are baking in the sun.
A conservative approach to terrain is a great way to ease into your day while assessing along the way.
Summary
Confidence
Weather Forecast
Wednesday: A mix of sun and cloud with strong solar input and light ridgetop wind from the southwest. Freezing level 1700 m and alpine temperatures near -4 C.
Thursday: WARM. Freezing levels rise to 3000 m by the afternoon. Alpine temperatures +3C and ridgetop wind moderate from the southwest.
Friday: Cloudy and warm. No overnight freeze and freezing levels remain near 3000 m. Alpine temperatures near +3C. Freezing levels should drop to 1400 m by Saturday with alpine temperatures near -10 C.
Avalanche Summary
Sunday night's storm showed evidence of a widespread natural avalanche cycle up to size 3 on Monday but the average storm/ wind slabs were reported to size 2 and failed in the recent storm snow. Some larger avalanches may have failed on the end of March melt-freeze crust. Most notable was a natural size 3.5 storm slab that started at 2600 m and ran to the valley bottom.
Avalanche hazard will likely spike on Wednesday with sunshine and the effects of solar radiation on the recent storm snow.
Snowpack Summary
Wednesdays' sun and warming will likely create moist/ wet surface snow on all aspects up to 1500 m and to the mountain top on southerly slopes.
15 to 30 cm of storm snow has blanketed the region and buried multiple crusts in the upper snowpack. Moderate to strong west/ southwest wind will be redistributing the new storm snow in exposed high elevation terrain forming wind slabs and developing large cornices.
The new snow brings 50-70 cm above will a crust from late March. The amount of snow on the crust tapers rapidly at lower elevations. This crust is present on all aspects up to an elevation of 2600 m. Below the crust, the snow is moist.
The early-December rain crust is approximately a metre off the ground. Large slab avalanches have failed on this interface earlier last week following a rain and warming event. This layer may be dormant now due to colder weather and a good overnight refreeze, however, it may appear again during the next big warm-up or with increased load from wind, snow and/or rain.
Terrain and Travel
- Watch for changing conditions today, storm slabs may become increasingly reactive.
- Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
- If triggered loose wet avalanches may step down to deeper layers resulting in larger avalanches.
- Cornices become weak with daytime heating or solar exposure.
- The more the snowpack warms-up and weakens, the more conservative you`ll want to be with your terrain selection.
Problems
Loose Wet
Sun and warm temperatures will weaken the snow surface on sun-exposed slopes, creating wet avalanches. Watch for wet and heavy snow and be aware of overhead exposure to big sunny slopes.
Wet loose avalanches could trigger deeper wet slabs.
Aspects: East, South East, South, South West, West.
Elevations: All elevations.
Likelihood
Expected Size
Storm Slabs
Up to 30 cm of new storm snow has accumulated throughout the region building fresh storm slabs. The slabs will be most reactive where they overlie a crust and when the sun comes out.
Moderate to strong southwest wind has redistributed the new snow forming wind slabs in lee terrain features in the alpine and at treeline.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Springtime cornices are large and unpredictable. The sunshine can pack a punch and lead to cornice failures. Give them a wide berth when travelling at ridge crest and avoid overhead exposure.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 6th, 2022 4:00PM
