Avalanche Forecast

Issued: Apr 9th, 2014 4:20PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Deep Persistent Slabs, Cornices and Wind Slabs.

snow safety, Parks Canada

Banff Yoho Kootenay.

Spring conditions are arriving. High North terrain offers the best skiing and early starts and finishes are important. Daytime heating will increase the hazard especially in thin snowpack or rocky areas where the basal facets could be triggered.

Summary

Weather Forecast

Thursday will have some light flurries with gusty West winds and alpine temperatures between -11'C and -2'C. Friday will also have light flurries, freezing levels around 1800m and gusty west winds. Saturday is a mix of sun and cloud with light winds and alpine temperatures between -6'C and 0'C.

Snowpack Summary

Moist snow to 2000m on all aspects and to ridge top on solar aspects. Wind slabs forming in open areas. Western areas such as Emerald and Field have a deep and stable snowpack. The Lake Louise, Hwy 93 N, & Sunshine areas have a weaker snowpack and we are still getting easy to moderate sudden collapse results on the basal depth hoar in some areas.

Avalanche Summary

Cascade Waterfall and Rogans gulley both produced size three avalanches to ground yesterday afternoon during the warm up. Several other natural slides to ground in shallow areas have been reported by our nearest neighbors today as well as a few natural cornice failures. These will continue to occur with daytime heating over the next day or two.

Confidence

Problems

Deep Persistent Slabs

Daytime warming in thinner snowpack areas or larger triggers such as cornices may trigger this weakness. Thin rocky snowpack areas may also be susceptible to skier triggering.

Avoid shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Cornices

Several natural cornice failures have been observed in the last two days caused by new snow loading and warm temperatures. Minimize exposure to overhead cornices.

Cornices become weak with daytime heating, so travel early on exposed slopes.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Wind Slabs

Gusty SW winds have formed new wind slabs in immediate lee areas.

Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 10th, 2014 4:00PM