Avalanche Forecast
Regions: Banff Yoho Kootenay.
Our danger ratings are for the highest level we expect to see over the course of the day. The heat and solar inputs will be the main factors for the increase in avalanche danger. Start early and end early, to take advantage of the overnight recovery.
Weather Forecast
Warm temperatures and clear skies will continue through the weekend. Daytime highs at valley bottom will climb to +13 with freezing levels as high as 2500m. 3000m winds will gradually increase through the weekend with values in the moderate to strong range by Sunday. Solar inputs will pack a punch on steep southerly aspects by mid day.
Snowpack Summary
10-20cm recent snow remains preserved on Northerly aspects and low angle terrain, on steep solar aspects a surface crust has formed. Some recent wind effect at higher elevations that seems limited to ridge crests. Recent profiles show the Feb. 19 and Jan. 27 facets in the upper meter with hard to no results. Cornices are huge.
Avalanche Summary
No new avalanches reported today with good visibility. Earlier this week several large persistent slabs were reported in high north aspects and we assume these were triggered by large cornice falls. We expect an increase in avalanche activity as day time heat and strong solar inputs effect the snowpack.
Confidence
Timing or intensity of solar radiation is uncertain
Avalanche Problems
Loose Wet
This weekend will bring an increase in freezing levels and solar input. We should see some recovery over night, but watch afternoon solar effect as conditions can deteriorate quickly.
- Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.
Aspects: East, South East, South, South West, West.
Elevations: All elevations.
Likelihood: Possible - Likely
Expected Size: 1 - 2
Persistent Slabs
We have had a few persistent slabs triggered by cornices (which are large!) over the past few days, mainly on alpine N aspects. If solar slopes start to break down from heat on Friday, these weak layers could reawaken on other aspects and elevations.
- Pay attention to overhead hazards like cornices which could trigger the persistent slabs.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Unlikely - Possible
Expected Size: 2 - 3
Wind Slabs
We suspect moderate winds have created isolated wind slabs on immediate lee slopes in the alpine. Though small in size, this problem could pose a significant hazard in the wrong terrain.
- Watch for pockets of windslab in steep alpine features.
Aspects: North, North East, East.
Elevations: Alpine.
Likelihood: Unlikely - Possible
Expected Size: 1 - 1.5