Recently formed wind slabs are expected to remain reactive to human-triggering on Thursday. Extra caution is required on steep south-facing slopes in the afternoon if the sun is out in full force.
Summary
Confidence
Moderate - Timing or intensity of solar radiation is uncertain
Weather Forecast
A mix of sun and cloud is expected on Thursday. Freezing levels are expected to reach around 1900m in the afternoon and alpine winds are forecast to be moderate to strong from the southwest. Mostly sun conditions are expected for Friday with freezing levels climbing to over 2000m and moderate to strong southwest winds in the alpine. A weak storm pulse may bring a few millimeters of precipitation on Saturday and freezing levels are forecast to reach around 2300m.
Avalanche Summary
On Wednesday, two natural size 1.5 storm slabs were reported from the north of the region. These were 30cm thick and released on an southeast-east aspect in the alpine. A natural size 1.5 loose dry avalanche was also reported in the north from an east aspect gully feature in the alpine. In the southeast of the region, several size 1 wind slabs were ski cut on north through east aspects at 1800-2100m elevation. These were 10-30cm thick on steep leeward features around ridge crests.
Snowpack Summary
Wind slabs on lee aspects in alpine and open treeline. 15-20cm recent storm snow is sitting on a crust at most elevations and aspects which will increase the distance that small avalanches run. The mid February layer is down 30-60cm and is a crust in most areas. This layer is generally well bonded to the overlying persistent slab. However, in isolated ares there is surface hoar or facets overlying this crust making the interface much more likely to produce large avalanches.
rbuhler,
Avalanche Canada
