Avalanche Forecast
Issued: Feb 7th, 2016 4:00PM
The alpine rating is Wind Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeEvidence of a widespread avalanche cycle in the Yoho Valley today. Windslabs remain very touchy. Stick to low angle moderate terrain and move through the mountains conservatively for a few days yet.
Summary
Weather Forecast
A warming trend will influence the forecast region starting mid week. It is unknown at this point as to how much the trend will affect the snowpack. Until then expect continued moderate to strong at high elevations with little to no precipitation.
Snowpack Summary
Wind slabs exist in the alpine and at tree line that are easy to trigger. The Jan 6 surface hoar/facet/sun crust layer, down 40-100cm, is becoming less reactive to skier triggering, however sudden collapse results persist on the Jan 6 and Dec 3 layers. Isolated whumphing on mid-pack facets/surface hoar have been observed this past week.
Avalanche Summary
A major avalanche cycle occured on Saturday (Feb 6). Many slabs up to size 2.5 were observed throughout the Yoho Valley today. Cornices appear to be fragile due to the strong wind yesterday.
Confidence
Problems
Wind Slabs
New snow and very strong wind on Saturday have created touchy wind slabs in the alpine. These slabs are still very susceptible to human triggering.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
An average of 40-100 cm overlies the Jan 6 layer of surface hoar, facets and sun crust. Test results on this layer show it has become stubborn to trigger, but potential for wide propagation remains. The new snow will increase the likelihood of this.
- Use careful route-finding and stick to moderate slope angles with low consequences
- Avoid open slopes and convex rolls where buried surface hoar may be preserved.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 8th, 2016 4:00PM