Avalog Join
Archived

Avalanche Forecast

Jan 14th, 2013–Jan 15th, 2013
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
3: Considerable
The avalanche danger rating below treeline will be considerable
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
3: Considerable
The avalanche danger rating below treeline will be considerable
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
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: South Columbia.

This forecast is based on a weather model that shows rapidly increasing alpine temperatures on Tuesday. If it doesn’t warm up, then these danger ratings are one notch too high.  See the forecasters blog for warming details.

Confidence

Poor - Timing, track, or intensity of incoming weather is uncertain

Weather Forecast

Monday night and Tuesday: A high pressure dominates the weather bringing dry conditions. Freezing level are expected to rise up to 2500 m. and the sun to shine in the alpine with valley clouds. Winds should be strong from the Northwest.Wednesday: Dry, sunny and warm conditions persist. Thursday: A cold front should lower freezing levels and bring a trace of precipitation.

Avalanche Summary

A few recent natural slab avalanches up to size 2.5 on steep South and Northwest aspects were reported in the Northern part of the region. There was also several natural and skier triggered slab avalanches up to size 1.5 on various aspects all over the region.

Snowpack Summary

The upper snowpack instabilities that were starting to settle could become unstable again if rapid warming occurs with the forecasted weather for the next 2 days. Read the forecaster blog to learn more about this process. The 50-90 cm of recent snow is sitting over weaker snow surfaces including surface hoar (found especially at and below treeline in sheltered areas), a sun crust (on steep S to SW -facing slopes) and facets. The distribution of buried surface hoar is patchy, but where it exists, it may become touchy again. Recent strong winds have also left wind slabs in the lee of terrain breaks such as ridges and ribs at alpine and treeline elevations. A strong mid-pack overlies a weak facet/crust layer near the base of the snowpack, which is now considered inactive.

Avalanche Problems

Persistent Slabs

Be aware of rapid warming and solar radiation forecasted tomorrow and Wednesday which will most likely weaken the snow surface, possibly triggering an avalanche on the surface hoar layer down around 80 cm.
Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.>Avoid paths that have not avalanched recently.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 5

Wind Slabs

New wind slabs may be found behind terrain breaks such as ridges and ribs. These could be triggered by rapid warming and sun radiation over the next few days.
Cornices become weak with daytime heating, avoid traveling on slopes exposed to them.>Be aware of the potential for wide propagations due to the presence of hard windslabs.>

Aspects: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 5