Avalanche Forecast
Issued: Mar 26th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
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Avalanche Canada
Human triggered avalanches are possible. Watch for changing snow conditions when you gain elevation and transition into open wind affected terrain.
Summary
Confidence
High - The number, quality, or consistency of field observations is good, and supports our confidence.
Weather Forecast
FRIDAY NIGHT: Cloudy, 20 km/h northwest wind, treeline temperatures around -4 C.
SATURDAY: Mix of sun and cloud with some light flurries but no notable accumulations of snow, 30-40 km/h southwest wind, freezing level up to 1700 m, treeline temperatures around -2 C.
SUNDAY: Flurries with 10-20 cm of snow, 40-50 km/h southwest wind, freezing level up to 1500 m, treeline temperatures around -3 C.
MONDAY: Another 10-15 cm of snow by the morning then mostly cloudy during the day, 30 km/h northwest wind, freezing level drops to valley bottom and treeline temperatures drop to -8 C.
Avalanche Summary
Avalanche activity over the past few days has primarily been small (size 1-1.5) dry loose avalanches in the top 20 cm of snow and some small cornice failures that did not trigger any slabs. However, each day there have been a few notable slab avalanches. On Thursday a natural size 3 avalanche was observed on a east aspect at 1800 m in the Valhallas. The crown 100 cm thick, but no other details are known. On Wednesday there was a size 2 skier triggered avalanche on a east facing slope at 2250 m in the southern Selkirks (running on a 30 cm deep crust layer).
On Saturday there will be a lingering possibility to trigger storm slab, wind slab, and dry loose avalanches in the upper snowpack.
Snowpack Summary
At alpine and treeline elevations 10-20 cm of recent snow sits above sun crusts on solar aspects and small surface hoar on shaded aspects. 30-50 cm of snow has accumulated above an interface that formed during the mid-March dry spell, which consists of a widespread crust (except on north-facing slopes above 1800 m). Overall the snow seems to be bonding well to these interfaces, although there have been a few isolated avalanches running on crusts layer over the past few days. Lower elevations have undergone daily melt-freeze cycles, with moist or crusty surfaces likely found up to at least 1800 m.
Terrain and Travel
- Be careful with open slopes and convex rolls, especially in more extreme terrain.
- Use ridges or ribs to avoid areas of wind loaded snow.
- Minimize exposure to sun-exposed slopes when the solar radiation is strong.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Problems
Storm Slabs
While the upper snowpack is generally strong, slab avalanches are still possible on some steep terrain features. The most likely spot to find reactive slabs is in lee terrain features where there has been recent wind loading. There are also some surface hoar and crust layers in the top 50 cm of the snowpack, and while none of these layers are overly concerning, they may act as sliding layers.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 27th, 2021 4:00PM
