Avalanche Forecast
Issued: Mar 24th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Deep Persistent Slabs, Persistent Slabs and Loose Dry.
AL,
Avalanche Canada
An Easterly flow will bring snow to the Eastern slope of the Rockies. In areas where this new snow overlays crusts, expect to see loose dry avalanches activity.
Summary
Confidence
Avalanche Summary
No new avalanches were observed or reported Friday.
Snowpack Summary
Surface sun crusts exist to ridgetop on solar aspects and to 2000 m on shady aspects. The middle of the snowpack holds several crust layers that has produced numerous natural slab avalanches over the past 10 days. The base of the snowpack is weak, unconsolidated depth hoar in almost all areas.
Weather Summary
A North Easterly flow will affect the forecast region this weekend. Increased cloud cover and light precipitation will begin Friday night with snowfall accumulation values of 5-15cm (more to the East). Due to the convective nature of the weather system, snowfall values could vary from valley to valley. Daytime High freezing levels will climb to 1500m. Ridgetop winds will remain in the light to Moderate range.
Terrain and Travel Advice
- Uncertainty is best managed through conservative terrain choices at this time.
- Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
Problems
Deep Persistent Slabs
The weak depth hoar at the bottom of the snowpack inspires little confidence. Multiple parties have remotely triggered large slabs from thin areas in the snowpack. Give careful consideration to the slopes overhead as large avalanches may run well into the runout zone or into lower-angle terrain. Avoid big terrain features and be especially cautious in thin or rocky areas, where triggering is more likely.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
Three persistent weak layers formed in January are down 40-110 cm. Buried sun crusts on steep solar slopes present the greatest concern for triggering, however, weak facets and isolated surface hoar can be found on the same interfaces on shaded aspects.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Dry
Incoming snowfall will overlay a supportive crust on all aspects below 2000m and to ridgetop on solar aspects. We expect this new snow to bond poorly to the crust. As storm snow accumulates we will likely see it shed on the crust interface, and form loose dry avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Mar 25th, 2023 4:00PM
