Storm slabs may become more sensitive to human triggering Thursday as temperatures rise. This forecast is based on very little snow falling on Thursday, if storm snow starts to exceed 20 cm, the hazard will bump up to considerable at all elevations.
Confidence
Low - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
The current weather pattern is rather complex, and the weather models are not in agreement, so take this weather forecast with a grain of salt.WEDNESDAY NIGHT: Freezing level at valley bottom, around -10 C in the alpine, light south/southeast wind, no significant snowfall expected.THURSDAY: Overcast, freezing level rising to 1600 m, light to moderate south/southeast wind, precipitation beginning in the afternoon, 2 to 10 cm expected. 10 to 20 cm possible Thursday night.FRIDAY: Overcast, freezing level at 600 m, light south/southeast wind, 5 to 10 cm of snow possible.SATURDAY: Broken cloud cover, freezing level around 600 m, light variable wind, 1 to 5 cm of snow possible.
Avalanche Summary
On Tuesday there was a bit of small (size 1) loose dry activity, but these were not running very far. Over the weekend, small size 1 wind slabs were reactive to skier traffic.
Snowpack Summary
The South Coast mountains have picked up 25 to 40 cm of new snow over the past few days. Winds have likely formed fresh wind slabs in wind exposed features. The new snow rests on a variety of wind affected surfaces from scoured to wind-pressed to stiff old wind slabs that were formed during a previous extreme wind event. The new snow may be resting on isolated pockets of facets in sheltered locations. Below that, the snowpack is well-settled and strong.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.