Avalanche Forecast

Issued: Mar 30th, 2016 8:05AM

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

Parks Canada danyelle magnan, Parks Canada

Mild overnight alpine temps prevented a good overnight recovery. The sun and warm temps today will quickly break down crusts. Be very cautious on slopes where the snow is becoming moist. On steep solar aspects avalanche danger may rise to High.

Summary

Weather Forecast

A strong ridge of high pressure will bring strong sun and warm temps. Today alpine temps of 4'C with freezing levels to 2500m and generally light winds will rapidly break down the surface crust. Overnight a weak temp inversion will prevent a strong recovery. Thursday and Friday will be similar with freezing levels rising to 2800m.

Snowpack Summary

A spring melt-freeze cycle is just beginning on solar aspects and at lower elevations. Where it exists the surface crust is still relatively thin and will break down quickly. On shaded aspects the snow remained dry yesterday but that will change today. There are multiple crusts in the top meter. Wind slabs can be found in alpine lee features.

Avalanche Summary

Solar and warm temperatures have been triggering loose wet avalanches, as well as slab avalanches up to size 3 over the past few days. Recent activity has been primarily from sun exposed slopes, as temps had remained relatively cool at higher elevations with good overnight recoveries. Glide crack releases and cornice failures have been occurring.

Confidence

Problems

Loose Wet

An icon showing Loose Wet
Temps were warm overnight and the weak surface crust will break down quickly. Snow on N-E aspects at higher elevations that previously remained dry will deteriorate with warm temps today. Travel early and be very cautious as the snow becomes moist.
Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.Watch for clues, like sluffing off of cliffs, that the snowpack is warming up.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Cornices

An icon showing Cornices
The strong solar will weaken cornices, which are very large on many ridges. Cornice failures are likely triggers for deeply buried weak layers and can trigger large avalanches.
Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.Extra caution needed around cornices with current conditions.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

2 - 3

Persistent Slabs

An icon showing Persistent Slabs
Intense solar and warm temps could wake up deeply buried weak layers. Recent tests on these crusts indicate that they will likely take a heavy trigger like a cornice fall or another avalanche, but if triggered very large avalanches are possible.
Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.Choose well supported terrain without convexities.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 4

Valid until: Mar 31st, 2016 8:00AM