Avalanche Forecast

Issued: Apr 18th, 2023 4:00PM

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

Avalanche Canada swerner, Avalanche Canada

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Storm slabs may be reactive to human triggers on Wednesday, especially if your local riding area receives 15 cm+ of new snow overnight.

Summary

Confidence

Low

Avalanche Summary

No new avalanches were reported on Tuesday. Loose wet pinwheeling from steep solar aspects was seen during short periods of sunshine.

Observations are very limited at this time of year, please consider sharing any information or photos you have on the Mountain Information Network to help guide our forecasts.

Snowpack Summary

Up to 25 cm of new snow by Tuesday morning brings recent storm snow to 35-50 cm (rain below 600 m). The recent snow and extreme southerly wind have formed new storm slabs.

At upper elevations, the recent snow is likely sitting on hard surfaces on windward aspects and settled old snow on northerly aspects. However, northerly aspects did show sudden planar test results on an interface down 45 cm. Below 1400 m, the recent snow is sitting on a crust on all aspects.

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

Weather Summary

Tuesday Night

Mostly cloudy with flurries 5-15 cm. Ridgetop winds 20-45 km/hr from the southeast. Temperature at treeline around -3 C and freezing level 500 m.

Wednesday

Mix of sun and cloud with isolated flurries 3-15 cm. Ridgetop wind 30 km/h from the southwest. Temperature at treeline around -1 C with freezing levels near 1000 m.

Thursday

Cloudy with isolated flurries 3-10 cm. Ridgetop wind 25 to 45 km/h. Temperature at treeline around -1 C and freezing level near 1000 m.

Friday

Cloudy with light precipitation. Ridgetop wind 30 km/h from the south. Temperature at treeline around 0 C and freezing level 1100 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
  • Use small low consequence slopes to test the bond of the new snow.

Problems

Storm Slabs

An icon showing Storm Slabs

35-50 cm of new snow and extreme southerly wind have formed fresh storm slabs at upper elevations.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Apr 19th, 2023 4:00PM