Avalanche Forecast
Issued: Mar 3rd, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
Ross Campbell,
Exercise extra caution on southerly aspects if the sun comes out! The Solar radiation in March can pack some punch!
Summary
Weather Forecast
We are into a cooling/drying trend after our warm wet weather from earlier this week as a High-Pressure system moves over Rogers Pass. On Friday we are expecting a mix of sun and cloud, light NE winds and the FL falling to 1300m. The same conditions are expected over the weekend, but with more sun and less cloud.
Snowpack Summary
Cooling temps Thursday evening will create a crust at lower elevations. Earlier this week at TL we received ~45cm of snow, warm temps, and strong winds creating storm slabs. The new snow overlies the Feb 26th interface which consists of surface hoar, crusts, facets, and hard wind slabs depending on aspect elevation, incline, and terrain feature.
Avalanche Summary
HWY corridor: Avalanche control on Tuesday evening produced numerous avalanches to size 3.5. We also obs several natural avalanches to size 2 in the last 48 hours.
From Wednesday in the Backcountry: Multiple reports of human-triggered avalanches to size 2 in the Connaught drainage, and a MIN report of touchy storm slabs on Glacier Crest.
Confidence
Timing, track, or intensity of incoming weather system is uncertain
Problems
Storm Slabs
Storm slabs buried a mix of surfaces; sun crust on steep solar aspects, small surface hoar around Treeline and below, facets and firm wind slab elsewhere. S'ly aspects with sun crusts and low elevation unsupported rolls may be more sensitive.
- Lingering storm slabs may still be reactive on specific terrain features
- Convex features and steep unsupported slopes will be most prone to triggering.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
A persistent weak layer of surface hoar and/or sun crust sits 60-90cm down, depending on wind loading and aspect. With elevated temps and a new snowload, this layer may be reactive in areas where it has not previously slid.
- Persistent slabs may be more sensitive to human triggering on solar asp where they sit on sun crust
- Persistent slabs will be most susceptible in steep unsupported terrain with a shallow snowpack
Aspects: All aspects.
Elevations: Treeline.
Likelihood
Expected Size
Valid until: Mar 4th, 2022 4:00PM
