Avalanche Forecast
Issued: Jan 2nd, 2019 4:44PM
The alpine rating is Storm Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeA vigourous storm system is forecast to bring heavy amounts of snow and moderate to strong winds to the region Wednesday night through Thursday.
Summary
Confidence
Moderate - Intensity of incoming weather systems is uncertain on Thursday
Weather Forecast
WEDNESDAY NIGHT: Snow, accumulation 15-25 cm / Moderate southwest wind / Alpine temperature -7 C THURSDAY: Snow, accumulation 20-30 cm / Moderate to strong southwest wind / Alpine temperature -3 C / Freezing level 1200 mFRIDAY: Snow, accumulation 10-15 cm / Moderate to strong south wind / Alpine temperature -7 C SATURDAY: Scattered flurries / Light to moderate west wind / Alpine temperature -6
Avalanche Summary
Expect to see widespread avalanche activity on Thursday as a vigorous storm passes through the region Wednesday night through Thursday.A notable MIN report from Saturday describes a large (size 2) snowmobile remote (from a distance) triggered storm slab in the Clemina Creek area. (link here) Another recent notable event was a large (size 2.5) persistent slab release that was skier triggered below a ridgecrest on a southwest aspect in the Connaught Creek area in Glacier National Park.
Snowpack Summary
20-30 cm of new snow falling Wednesday through the day and night will add to the 30-40 cm of snow that fell last weekend. Moderate to strong southwest winds along with a rise in freezing level associated with the latest weather system is expected to promote storm slab development at all elevations.An aspect-dependant mix of facets, surface hoar, and sun crust buried mid-December now 100-150 cm deep, is reported to be less reactive in snowpack tests and showing signs of strengthening. A heavy trigger might still coax reactivity out of steep north and east facing slopes between 1900-2300 m or a steep south-facing slope in the alpine.The lower snowpack is generally strong and settled, with a crust that formed in late October near the bottom of the snowpack.
Problems
Storm Slabs
Heavy snowfall combined with a rising freezing level and moderate to strong southwest wind will promote storm slab development. Deepest deposits will be found in alpine and treeline lee terrain.
If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.Minimize exposure during periods of heavy loading from new snow, wind.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 3rd, 2019 2:00PM