Avalanche Forecast

Issued: Feb 7th, 2016 4:00PM

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

deryl kelly, Parks Canada

Jasper.

Warming trend Monday and continuing through the week (our first taste of spring conditions) will shift the hazard quickly over the day. Not to worry, winter will return!

Summary

Weather Forecast

Progressive spring like conditions for the week in the forecast area. The sun will have a strong punch on any solar aspects for Monday and freezing levels will jump to over 3000ms by Tuesday with a strengthening diurnal cycle. Expected day time temperatures to get above 0 with some recovery overnight. Pack your skin wax, sunglasses and tanning oil!Â

Snowpack Summary

New wind slab formed at tree-line and above on North-Easterly aspects below ridge crests and cross-loaded terrain. These slabs are loading a weak and facetted mid-pack that has a layer of concern down about 30 to 60cm at the interface between old facets and new snow. Isolated pockets of decomposing surface hoar at tree-line down 40cm.

Avalanche Summary

No new avalanches reported

Confidence

Timing or intensity of solar radiation is uncertain on Monday

Problems

Wind Slabs

New wind slab formed on lee and cross-loaded terrain. This is in addition to previous slabs found up to 30cm thick formed during the storm at the end of last week and sitting on a weak facetted interface.

Be aware of the potential for wide propagations due to the presence of hard windslabs.Caution in lee and cross-loaded terrain near ridge crests.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Loose Wet

Expect any wet slide will have the potential to trigger preserved persistent slabs below. These slabs may take the season snowpack with it and will be notably destructive. South facing ice features could become very dangerous to an unaware climber

Avoid ice climbs exposed to steep rocky terrain on solar aspects during the middle of the day.Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

35cm of storm snow from last week has formed a slab overlying a weak facetted snowpack. Field teams have found decomposed surface hoar with sudden planar test results in isolated locations at tree line. This is the key interface to assess.

Use caution on open slopes and convex rolls Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Feb 8th, 2016 4:00PM