Avalanche Forecast

Issued: Mar 15th, 2017 4:06PM

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

aaron beardmore, Parks Canada

Banff Yoho Kootenay.

Rain and warm temperatures continue to induce a large avalanche cycle. A cooling trend on Friday will be short lived, after which a second wave of weather will impact the forecast region.

Summary

Weather Forecast

Continued warm temps are expected tomorrow followed by a cooling trend on Friday. The wind is supposed to stay elevated in the strong range from the West. A second wave of precip is expected, yet again, on Saturday, accompanied by temperatures near zero.

Snowpack Summary

Additional snowfall and very warm temperatures have tipped the snowpack and an avalanche cycle is still underway. A 50 cm dense slab has overloaded two prominent weaknesses in the snowpack; one down 40cm and the other in facets near the base of the snowpack. Expect rain soaked snow at low elevation and a continued avalanche cycle.

Avalanche Summary

A major avalanche cycle is underway, avoid avalanche terrain.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Saturday

Problems

Deep Persistent Slabs

The entire snowpack is built upon a structurally weak base, which is producing very large avalanches. Large deep persistent slabs have been observed and some are running into the valley bottom.

Use conservative route selection, choose moderate angled and supported terrain with low consequence.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

2 - 4

Wind Slabs

A 40-50cm cohesive windslab exists at higher elevations, and in wind effected areas near treeline. This slab reacts easily to tests and continues to produce avalanches

Be aware of the potential for wide propagations.

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 3

Valid until: Mar 16th, 2017 4:00PM