Avalanche Forecast
Issued: Feb 17th, 2020 5:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
shorton,
Avalanche Canada
Carefully assess terrain where triggering storm slabs is possible such as slopes that are getting hit by the sun, wind-loaded, or steep and convex.
Summary
Confidence
Moderate - Uncertainty is due to how quickly the snowpack will recover and gain strength.
Weather Forecast
MONDAY NIGHT: Partly cloudy, moderate northwest wind, alpine temperatures drop to -12 C.
TUESDAY: Sunny with a few clouds, light northwest wind, alpine high temperatures around -6 C.
WEDNESDAY: Sunny, light south wind, alpine high temperatures around -6 C.
THURSDAY: Sunny, moderate south wind, alpine high temperatures around -6 C.
Avalanche Summary
Avalanche activity has been on the decline over the weekend as stormy weather has eased. A few size 1-2 natural storm slab avalanches were reported on Sunday, primarily in wind affected terrain on north and east aspects. Several small (size 1) human triggered slabs were reported as well. See some photos of recent human triggered slabs on Friday from the Mountain Information Network (here and here). On Saturday, there were reports of whumpfing at Sugarbowl which suggests recent snow could remain reactive in some sheltered terrain, or perhaps that instability was only shortly lived. Overall, triggering storm slab avalanches will remain possible in the coming days.
Snowpack Summary
The past week of stormy weather delivered up to 80 cm of new snow to the Cariboos. The deepest reported amounts were along the Robson Valley, while most parts of the region received at least 40 cm. Up to now it has primarily been a problem on wind-loaded slopes, but as this snow settles into a slab it could become reactive on sheltered slopes too. In some areas this new snow may sit above small surface hoar (in open terrain at treeline), sun crusts (in open south-facing terrain), or a thick rain crust (below 1700 m). Overall there is some uncertainty about whether storm slabs will gain or loose strength in the coming days. The mid and lower snowpack are generally well settled and strong.
Terrain and Travel
- Start on smaller terrain features and gather information before committing to bigger terrain.
- Give the new snow several days to settle and stabilize before pushing into bigger terrain.
- Avoid exposure to steep, sun exposed slopes, especially when the solar radiation is strong.
Problems
Storm Slabs
40-80 cm of snow from the past week is gradually settling and gaining strength, but it could still be possible to trigger storm slabs in wind affected or steep convex terrain.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 18th, 2020 5:00PM
