Avalanche Forecast

Issued: Apr 1st, 2016 6:12PM

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

rupert wedgwood, Parks Canada

Jasper.

Start your trips early and finish early, run for cover if the sun comes out in the afternoon.

Summary

Weather Forecast

Overnight temperatures will have the freezing level close to Treeline.Â Light precipitation in the form of rain or flurries is forecast on Saturday. Temperatures will be cooler over the weekend with freezing levels on the weekend rising to 2400m. Winds are light westerly. Cooling on Monday eventing may allow a good overnight valley bottom freeze.

Snowpack Summary

Snow conditions are isothermal below 2200mÂ on all but the most northerly facing slopes.Â South and Westerly facing terrain up to 2,400m has a well developed temperature crust at the surface if freezing occurs. Below 1,700mÂ this curst is present regardless of aspect. The snowpack at all elevations has a weak base and several mid-pack weaknesses

Avalanche Summary

A widespread avalanche cycle took place on Thursday evening with little overnight freezing this will likely occur again this evening. Numerous point releases from the alpine then triggered wet slabs that ran to ground. The largest events were on south and westerly facing and ran to size 2.5. Fewer slides are occurring on northerly terrain.

Confidence

Freezing levels are uncertain on Monday

Problems

Deep Persistent Slabs

This problem is becoming more active. When triggered, it will be big with serious consequences. Warm and sunny conditions will increase this danger. Steep sun facing rocks, cornice failures, and loose avalanches from above are on going.

Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.Watch for clues, like sluffing off of cliffs, that the snowpack is warming up.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 3

Cornices

Increase occurrence of 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.

Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.Cornices become weak with daytime heating.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Loose Wet

The problem will remain active over the weekend with freezing levels reaching 2,400m. The danger rating will increase particularly on thin snowpack zones if the sun comes out or rain occurs. Loose avalanches can initiate larger avalanches below.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.Be very cautious with gully features.

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Apr 2nd, 2016 4:00PM