Avalanche Forecast

Issued: Apr 2nd, 2022 4:00PM

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

rbuhler, Avalanche Canada

South Coast Inland.

The new snowfall with moderate to strong wind is expected to form new wind slabs in exposed terrain at higher elevations.

Solar-triggered wet loose avalanches are possible in the afternoon if the sky clears and the sun is strong.

Summary

Confidence

Low - Uncertainty is due to the timing, track, & intensity of the incoming weather system. Uncertainty is due to the timing or intensity of solar radiation and its effect on the snowpack.

Weather Forecast

Stormy conditions are expected between Saturday night and early Tuesday expect for a brief period late Sunday afternoon when a break between systems is expected. Snowfall amounts are uncertain with weather models showing substantial variability.

Saturday Night: Snowfall 3-6 cm, moderate to strong SW wind, freezing level low around 1000 m.

Sunday: Snowfall 5-20 cm, sunny breaks in the late-afternoon, moderate to strong SW wind, freezing level high around 1500 m.

Sunday night and Monday: Snowfall 15-30 cm, strong SW wind, freezing level high around 1400 m.

Tuesday: Lingering flurries in the morning, sunny breaks in the afternoon, light to moderate W wind, freezing level high around 1300 m.

Avalanche Summary

Early reports from Saturday include a skier-triggered size 1 wind slab on a northeast aspect at 2450 m which had an average thickness of 25 cm and slid on a melt-freeze crust.

On Friday, a ski cut in the north of the region triggered a size 1 wind slab on a northeast aspect at around 2200 m elevation which was 15-20 cm thick. In the Coquihalla area, two natural cornice releases were reported on northwest aspects and a size 1 solar-triggered loose dry avalanche was observed in the alpine.

Snowpack Summary

The new storm snow will continue to bury a strong, supportive crust which extends to mountain top on solar aspects and to around 2200 m on northerly aspects. Strong southwest wind will be redistributing the new storm snow in exposed high elevation terrain forming touchy wind slabs.

The rest of the upper snowpack consists of a number of crust/facet/surface hoar interfaces buried in March that seem to have bonded well during the recent warm weather.

The middle and lower snowpack are generally strong and well bonded.

Terrain and Travel

Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
Wind slabs may be poorly bonded to the underlying crust.
Even brief periods of direct sun could produce natural avalanches.
As surface loses cohesion due to melting, loose wet avalanches become common in steeper terrain.

Problems

Wind Slabs

New snowfall with moderate to strong southwest wind is expected to form reactive new wind slabs on Sunday. These may be touchy where they overlie a firm crust.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Loose Wet

Rain at lower elevations on Sunday morning will increase the likelihood of human-triggered wet loose avalanches.

If the sun makes an appearance Sunday afternoon, solar-triggered wet loose avalanches should be expected on steep sun-exposed slopes.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Apr 3rd, 2022 4:00PM