Avalanche Forecast
Issued: Jan 23rd, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
cgarritty,
Avalanche Canada
Yet another storm pulse will keep storm slab problems active on Friday. The South Columbias are expected to receive the heaviest accumulations. Avalanche danger will increase over the day as new snow adds up.
Summary
Confidence
Weather Forecast
Thursday night: Cloudy with continuing flurries bringing 5-10 cm of new snow. Light to moderate southwest winds. Freezing levels remaining near 1400 metres.
Friday: Cloudy with increasing flurries bringing 10-20 cm of new snow. Light to moderate southwest winds. Alpine high temperatures around -2 with freezing levels to 1500 metres.
Saturday: Cloudy with isolated flurries and a trace of new snow. Light southeast winds. Alpine high temperatures around -4 with freezing levels to 1300 metres.
Sunday: Broken skies, becoming cloudy with isolated flurries and a trace of new snow. Light southeast winds. Alpine high temperatures around -5.
Avalanche Summary
There have been several reports over the past three days of natural, human and explosives triggered avalanches. Most of these were size 1-1.5 storm and wind slab avalanches, on northerly aspects in the alpine and at treeline.
Two notable persistent slab avalanches were reported on Tuesday, one natural and one explosives triggered, size 2.5 and 3.5 respectively. Both of these avalanches occurred in the alpine, on northerly aspects.
On Thursday, up to 15 cm of new snow (paired with warm temperatures and strong southerly winds) likely led to touchy storm slabs forming in many areas. Similar conditions are expected for Friday.
Snowpack Summary
Regular snowfall over the past week brought around 20-40 cm of snow to the region. Elevated winds and warm temperatures on Thursday mean that touchy new storm slabs were likely forming at higher elevations while melting of surface snow occurred below about 1500 metres. A similar picture is expected for Friday.
A layer of surface hoar may still be found roughly 80-120 cm deep in the Selkirks and 120-160 cm deep in the Monashees. This layer exists primarily at treeline and below treeline and through it appears to be gaining strength, it could still be triggered by a large load in some areas.
Terrain and Travel
- Storm slab size and sensitivity to triggering will likely increase through the day.
- Use increased caution at all elevations. Storm snow is forming touchy slabs.
Problems
Storm Slabs
Another period of snowfall overnight and through the day will keep storm slab problems active on Friday. Warm temperatures will likely promote slab formation in the new snow below treeline while thicker, wind-stiffened slabs continue to build at higher elevations.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 24th, 2020 5:00PM
