Avalanche Forecast

Issued: Jan 14th, 2013 4:00PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is moderate. Known problems include Wind Slabs and Loose Dry.

max darrah, Parks Canada

Jasper.

Inverted temperatures will mean that it will feel cold in the valley, while upper elevation start zones may be undergoing a rapid temperature increase. Ice climbers should avoid climbs below solar facing slopes.

Summary

Weather Forecast

The big story over the next few days is the spike in temperatures, especially up in the alpine. As a new warm and moist airmass slides in, this will introduce a rapid temperature change to a cold snowpack. Strong NW winds in the alpine and the possibility of rain below treeline. Possibility of intense solar radiation and inverted temperatures.

Snowpack Summary

Snowpack remains thin and facetted at lower elevations. Last week's storm snow has buried a surface hoar layer (Jan6) down approx 30cm. New windslabs at upper elevations that were previously stubborn to trigger may quickly become touchier as they undergo a rapid temperature change and increased loading with strong winds.

Avalanche Summary

Tuesday's warm temps will introduce rapid temperature change to a cold snowpack and may lead to a natural cycle and/or touchy slab conditions, as well as increased loose snow avalanches from steep solar aspects.

Confidence

Timing or intensity of solar radiation is uncertain

Problems

Wind Slabs

Last week's 30cm storm has produced new wind slabs on a variety of aspects. These slabs are resting on a surface hoar layer (Jan6) that is fairly widespread yet remains stubborn to triggers. Rapid warming will make these slabs easier to trigger.

Travel early before the heat of the day, and avoid big slopes in the afternoon.Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Loose Dry

Where wind has not affected the slope, 30cm of cold unconsolidated snow is sluffing out of steep terrain. Solar input and warming temps are expected to increase the frequency of these natural avalanches.

Avoid ice climbs that are exposed to steep rocky terrain on solar aspects.Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Jan 15th, 2013 4:00PM