Avalanche Forecast
Issued: Feb 13th, 2022 4:38PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
Tim Haggarty,
A modest helping of snow in the days to come should help to improve ski quality but may limit travel plans into the alpine with decreased visibility. Good skiing remains in sheltered areas at treeline and above.
Summary
Weather Forecast
A low will cross the divide Monday bringing around 5cm through Tuesday morning. Freezing levels should remain at valley bottom. SW winds may reach just into strong values in the alpine early Saturday as the warm front arrives and then increase a bit and shift northwest late in the day as the cold front follows through. Another system will follow..
Snowpack Summary
Extensive wind effect in exposed areas and wind slabs in lee areas at treeline and above. The Jan30 surface hoar/ sun crust interface remains reactive in isolated pockets. New sun crusts on solar slopes into the alpine and a thin temperature crust all aspects to 2100m. Shallow snowpack areas remain weak and faceted.
Avalanche Summary
One example Sunday of a skier remote avalanche at treeline in KNP and a few Saturday of naturals in the alpine in YNP. Visitor Safety staff in YNP observed what looked to be a sz 2.5 Na on NE aspect on Cathedral Crags at 2300m estimated at 200m wide 30-50 deep and at least 24 hrs old.
Confidence
Problems
Wind Slabs
While most exposed areas have been blown into hardpan... continue to watch for slabs in sheltered areas of the alpine and open areas right at treeline where a few reactive examples may linger in steep terrain.
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
The Jan 30 layer exists 30-50cm down as surface hoar on shady aspects and sun crust on steep solar aspects. This remains a concern mainly in isolated sheltered and shaded areas at, or just below, treeline, where surface hoar remains reactive in tests
- Dig down to find and test weak layers before committing to a line.
Aspects: North, North East, East, North West.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Valid until: Feb 14th, 2022 4:00PM
