Avalanche Forecast

Issued: Mar 15th, 2018 4:00PM

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

jonas hoke, Parks Canada

Jasper.

Incoming new snow should improve the skiing significantly. Check the bond of this new snow to the previous surfaces carefully before committing to any big terrain.

Summary

Weather Forecast

An unusual upper level flow is creating a weather pattern that is unusual and challenging for the weather models to predict.Friday: Cloudy with snow (up to 15cm). Alpine temps: Low -5 C, High -3 C. Ridge wind light. Freezing level: 1900m.Saturday: Flurries. (up to 5cm). Alpine temps: Low -7 C, High -3 C. Light ridge wind. Freezing level: 1900m.

Snowpack Summary

Fresh snow with light (gusting moderate) Northerly winds is building fresh storm slabs in exposed areas. Incoming snow is falling on a melt-freeze crust on solar aspects below 3000m and old facetted wind slabs on polar aspects above 1700m. The weak Feb. 8th interface under the old windslabs may remain a concern on high north aspects.

Avalanche Summary

No new avalanche activity has been observed or reported.

Confidence

Intensity of incoming weather systems is uncertain

Problems

Storm Slabs

Fresh storm slabs may sit on a hard melt-freeze crust on solar aspects, and facets on polar aspects, assess the bond at these interfaces carefully before committing to any avalanche start zones.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Use caution in lee areas. Recent wind loading have created storm slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Loose Wet

With the freezing level forecast to be as high as 1900m on Friday, this could be a significant problem at lower elevations (particularly on ice climbs).

Use caution above cliffs where small avalanches may have severe consequences.Avoid terrain traps, such as gullies, where the consequences of a small avalanche could be serious.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 1.5

Persistent Slabs

At upper elevations polar aspects still held cold, faceted snow and did not receive either solar triggers or significant snowpack settlement this past week. Steep, unsupported slopes should be treated with due respect.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1.5 - 2.5

Valid until: Mar 16th, 2018 4:00PM