Avalog
Register
Get forecast notifications
Create an account to receive email notifications when forecasts are published.
Register
Login
Archived

Avalanche Forecast

Dec 24th, 2019–Dec 25th, 2019
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate

Regions: Glacier.

While natural activity has tapered off, human triggered avalanches are still quite possible. Make conservative terrains choice. This is not the time to go all out.

Weather Forecast

Cloudy with sunny periods and isolated convective flurries bringing trace amounts of precipitation.  The alpine temperature will reach a  high -8 °C with the freezing level rising to 900m. Winds will be mostly light from the SW. Valley cloud is likely at lower elevations where a slight temperature inversion exist.

Snowpack Summary

The top 70cm of snow remains fairly unconsolidated in most places, and still has that post-storm powdery feeling. A new surface crust exists on steep solar aspects. The Dec 11th SH (5-12mm) is well preserved and is now down 90-120cm. The Nov 23 SH/Cr is down 160-185cm. Early season crusts still persist in the lower snowpack.

Avalanche Summary

Helicopter deployed explosives produced a large size 3.0 slab avalanche on Mt Fidelity, in an area that was previously uncontrolled. The natural avalanche cycle has tapered off, however human triggered avalanches in areas that haven't slid remain likely.

Confidence

Avalanche Problems

Storm Slabs

We're 2 days out from the last lashing of the storm and the storm snow remains reactive. Slab formation has been kept at bay by cold temperatures and light winds, but this snow can be triggered on convexities, cross loaded slopes and near ridgelines.

  • If triggered the storm slabs may step down to deeper layers resulting in large avalanches.
  • The new snow will require several days to settle and stabilize.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2

Persistent Slabs

The Dec 11th Surface Hoar(SH), size 5-12mm is down approximately 1m. Try to find this layer in your snow profile today; it is very recognizable. Most of the large natural avalanches that are currently visible in the backcountry slid on this layer.

  • Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones.
  • Be wary of slopes that did not previously avalanche.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible

Expected Size: 2 - 3.5