Avalanche Forecast

Issued: Mar 25th, 2016 4:00PM

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

garth lemke, Parks Canada

Jasper.

http://www.pc.gc.ca/apps/scond/Cond_E.asp?oID=23025&oPark=100244Human triggered avalanches are possible and have the potential to be large and destructive. Be cautious of thin snowpack areas and limit your exposure to large slopes. With warm afternoons its best to get an early start and end early.

Summary

Weather Forecast

Friday and Saturday will have 1600m freezing level with -10 Celsius overnight. Saturday will be variable cloud with periods of sun. Light westerly winds through weekend. Sunday-Monday will have increased clouds and 2-4cm of snow, perhaps higher amounts in Marmot basin area. Sunday night may have less of a freeze.

Snowpack Summary

Moist surface snow in the afternoons and isothermal conditions in shallow spots BTL on solar aspects. Overnight -10 Celsius helping with morning freeze. There is significant variation in snowpack depth through-out the area with a large proportion being shallow. The persistent slab down 30-70cms has been most active in the area around the ski hill.

Avalanche Summary

Thursday's field team in the Icefields area report only minor pin-wheels and snow-balling on immediate solar aspects. No field patrol Friday.

Confidence

Timing or intensity of solar radiation is uncertain on Saturday

Problems

Persistent Slabs

This problem has been most active in the Whistler/Portal Creek area but is widespread through the forecast region. When triggered, it will be big with serious consequences. Warm and sunny conditions will increase this danger.

Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Loose Wet

This problem is subject to intense periods of solar radiation. In shallow snowpack spots and sunny conditions, the danger rating will rapidly increase.

Avoid ice climbs that are exposed to steep rocky terrain on solar aspects.Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Cornices

Some cornice failures are being noted. It can act as a large trigger initiating deep weaknesses plus their sheer mass, whether or not it initiates an avalanche, would be like being hit by a car.

Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones.Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Mar 26th, 2016 4:00PM