Watch for changing conditions at higher elevations and be cautious around shallow snowpack areas where wind slabs could step down to deeper weak layers.
Summary
Confidence
High - The weather pattern is stable
Weather Forecast
A high pressure system sits over the Interior resulting in a fairly benign weather pattern until Friday. Wednesday/ Thursday: Clear skies with alpine temperatures near -11 and light easterly winds and freezing levels in the valley bottom. Friday: Cloudy with new snow amounts 8-15 cm. Alpine temperatures near -6 with ridgetop winds light from the southeast.
Avalanche Summary
On Monday, several size 2 wind slab avalanches were skier triggered in the lee of ridgetops and a natural cornice failure was able to entrain mass on the slope below but did not pull a slab. Also reported on Monday was a significant large natural avalanche (size 2.5) on a wind-loaded east facing slope in the Rossland range. This avalanche likely released on a deeper persistent weak layer.Expect wind slabs to linger on lee and crossloaded features at higher elevations.
Snowpack Summary
A variety of surface conditions exist including wind effected snow, sun crusts and surface hoar. Up to 50cm of settled snow now sits above an interface that was buried in mid-January. The interface is composed of facets, surface hoar, and/or sun crusts and the strength of this interface is reportedly variable. Recent snowpack tests have shown sudden results on that interface. Areas with thin snowpacks (e.g. less than 150 cm) have a generally weak snowpack structure with sugary facets near the ground. This includes shallow alpine slopes and most of the Rossland range. These deeper weaknesses warrant monitoring and create a complicating picture especially when it comes to terrain selection and decision making. These layers may sit dormant now with this stable weather pattern but they could reawaken with a change.
swerner,
Avalanche Canada
