Avalanche Forecast

Issued: Mar 12th, 2018 4:00PM

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

landon shepherd, Parks Canada

Jasper.

Highway 93 from Athabasca falls to Saskatchewan Crossing is closed for Avalanche control Monday and Tuesday

Summary

Weather Forecast

Strong high pressure with southern warm air will persist for another 2-3 days bringing rising freezing levels into the alpine and strong sun effect throughout the forecast zone. A small change is expected for later in the week with a return to more seasonable temperatures. Flurries may accompany the change of systems on Thursday.

Snowpack Summary

A relatively cold winter created a structurally weak snowpack slowly warming under spring-like temps and strong solar radiation. Settlement and sintering is occurring with warmer temps and melt-freeze crusts are developing on steep solar slopes. Mid and lower snowpack weaknesses persist but are not reacting to shear tests or natural triggers.

Avalanche Summary

Warm temps and rising freezing levels are resulting in loose dry avalanches on shaded slopes and loose wet avalanches on solar slopes to treeline. Avalanches treeline and below are not propagating widely, occurring to size 2, slowing in terrain that levels out or has dense vegetation. Alpine slopes have slab potential and should become more active.

Confidence

The weather pattern is stable

Problems

Loose Dry

Shaded aspects and elevations above the freezing level.

Avoid ice climbs that are in terrain traps below large start zones.Be careful of loose dry power sluffing in steep terrain..

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 2.5

Loose Wet

solar aspects and elevations below the freezing level

Cornices become weak with daytime heating. Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

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

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 2.5

Persistent Slabs

rising freezing levels and large triggers like cornice failures may wake up deeper slab instabilities

Be wary of large alpine slopes that did not previously avalanche.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 3

Valid until: Mar 13th, 2018 4:00PM