Avalanche Forecast
Regions: Banff Yoho Kootenay.
Monday looks like a great day to get out and enjoy the fresh snow on North aspects, just watch for recent wind loading. Start and finish early to optimize travel conditions and minimize any increases in avalanche hazard with day time warming.
Weather Forecast
Sunday night will see freezing levels drop to valley bottom and then rise to around 1700 m on Monday, with treeline highs around -4 C. Alpine winds will be in the light to moderate range out of the W and NW. Skies will be mostly clear so solar inputs may be fairly intense despite cooler air temperatures. No precipitation is expected.
Snowpack Summary
10-20 cm of new snow at treeline over previous crusts and wind effect. New wind slabs forming in alpine lee areas from moderate to strong SW-W winds. Moist snow on all aspects up to 1800 m and higher on solar aspects on Sunday. The March 19 crust interface is down 30-60 cm. Basal facets exist in shallow areas east of the divide.
Avalanche Summary
On Sunday loose dry sluffing was observed in steep alpine and treeline areas up to size 1.5 in the new snow. Ski hills reported ski and explosive triggered soft wind slabs in lee areas up to size 1.5. One size 3 cornice failure on Vulture Peak near the Wapta Icefields was also reported.
Confidence
Due to the number of field observations
Avalanche Problems
Wind Slabs
New wind slabs have formed in lee areas of the alpine from the new snow and wind on Sunday. These seem to be bonding ok, but may still be triggered by skiers especially at higher elevations where the wind loading was more intense.
- Watch for shooting cracks or stiffer feeling snow. Avoid areas that appear wind loaded.
- Be careful with wind loaded pockets, especially in steep confined alpine terrain.
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 2
Loose Wet
Strong solar inputs on Monday will increase the likelihood of small loose wet avalanches on steep solar aspects, especially in thin snowpack or rocky areas. Plan your day to avoid this type of terrain as the surface snow warms up.
- Minimize exposure when the solar radiation is strong, especially if snow is moist or wet.
Aspects: South East, South, South West, West.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 1.5
Cornices
Cornices are big and the springtime is when they fall off more frequently. We have had fairly regular observations of cornice failures over the past few weeks, so minimize your exposure to them especially as the day heats up or the winds increase.
- Cornices become weak with daytime heating, so travel early on exposed slopes.
Aspects: North, North East, East.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 2.5