Avalanche Forecast

Issued: Mar 21st, 2016 4:00PM

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

deryl kelly, Parks Canada

Jasper.

Increasing hazard possible over the day with a strong solar input. It is not a certainty but it's important to be aware of the rapid changes as we move into the spring.

Summary

Weather Forecast

Mild temperatures with freezing levels remaining at treeline and poor overnight recovery (re-freezing). Continued flurries through the evening Monday with rain or freezing rain possible below 1500ms. Tuesday afternoon is forecasting a break in the clouds as winds shift from the north and daytime temperatures drop.

Snowpack Summary

Rain soaked to 2000m with wet flurries to TL on all aspects. Generally, the snowpack is shallow and poorly consolidated with significant variation within the forecasting area. The persistent slab was found to be most active in Portal Creek and surrounding area off the ski hill. This layer will be triggered from thin spots on the slope.

Avalanche Summary

Poor visibility throughout the forecast region. Nothing new to report.

Confidence

Timing or intensity of solar radiation is uncertain

Problems

Persistent Slabs

This problem is still a concern in the Whistler/Portal Creek area. This, along with most recent rain means this area will be in very poor shape for travel.

Be aware of thin areas that may propogate to deeper instabilites.Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 3

Loose Wet

Freezing level expected to remain at treeline for Monday evening. If this is the case, the snowpack will be further weakened and hazard will continue to increase if daytime temperatures get above 0 degrees or with a strong solar input.

Avoid ice climbs that are in terrain traps below large start zones.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

Cornices

First indicators of this problem showing up. Easy enough to avoid but, larger slides, triggered in the deep weaknesses can quickly become a significant issue for groups traveling in the valley bottoms or run outs.

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

Possible

Expected Size

1 - 4

Valid until: Mar 22nd, 2016 4:00PM