Avalanche Forecast

Issued: Mar 14th, 2013 4:06PM

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

rupert wedgwood, Parks Canada

Jasper.

Avoid avalanche terrain at and above treeline. Skiers report triggering a size 2.5 avalanche in the Maligne area on Thursday.

Summary

Weather Forecast

Snowfall is expected to tapper off over the next 2 days. 5-10cm over the next 24hrs with the potential for more in the Icefields area. Cold arctic area is invading the valleys to the North and East. To the South, in the Icefeilds area, and at upper elevations warming moist air is giving inversion conditions. The colder air will prevail by Saturday.

Snowpack Summary

Soft to hard slabs are forming in the alpine under the influence of moderate to strong Westerly winds. In the Columbia Icefields area 70cm of new snow has fallen in the past 48 hours, 40cm of which fell in the past 24hrs. At treeline soft slabs exist in the most wind exposed terrain. Lesser amounts of snow fell near Jasper townsite.

Avalanche Summary

Poor visibility and flat light has obscured observations at treeline and above. The large snowfall amounts in the past 48 hrs and field tests in the alpine and treeline lead us to believe that avalanche activity is underway at upper elevations, both as point release and slabs. Cold temps in the north have stopped moist avalanche below treeline.

Confidence

Wind effect is extremely variable on Friday

Problems

Storm Slabs

70 cm of new snow has fallen in the Icefields area in the past 48hrs. This snow has formed stiffer wind slabs in the alpine than at treeline. Near treeline the slabs are softer and less sensitive to triggering. Moderate shears were recorded at 2450m.

Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.It is a good time to stay within the boundaries of a ski resort.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Loose Dry

Quantities of loose snow plaster steep cliffy terrain which is often encountered in and around ice climbs. With sufficient volume there currently to produce sizable avalanches, and more on the way, you would do well to avoid this terrain.

Avoid ice climbs that are in terrain traps below large start zones.Avoid travelling on ledges and cliffs where sluffing may have severe consequences.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

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