Avalanche Forecast
Regions: Purcells.
Avalanche danger is decreasing, but the potential for human triggered avalanches remains. Pay attention to how the weather is changing the snowpack through the day, as it could have an effect on travel and avalanche conditions.
Confidence
High - We have a good understanding of the snowpack structure and confidence in the weather forecast
Weather Forecast
THURSDAY NIGHT: Partly cloudy. No new rain/snow expected. Light variable winds, with some periods of strong northwest in the high alpine. Freezing level falling to around valley bottom.Â
FRIDAY: Partly cloudy with a drizzle of rain. Light southwest ridgetop winds, trending to moderate west in the high alpine. Freezing level rising to 2000 m through the day.
SATURDAY: Partly cloudy. Possible light rain/snow. Light southwest ridgetop wind trending to strong in the high alpine. Freezing level around valley bottom overnight, rising to 2200 m through the day.
SUNDAY: Partly cloudy. Possible light rain/snow. Light southwest ridgetop wind trending to strong in the high alpine. Freezing level rising as high as 2500 m.
Avalanche Summary
On Thursday, several loose wet avalanches up to size 1.5 were reported on slopes getting cooked by the sun.Â
On Tuesday, and Wednesday widespread loose wet avalanches were reported due to warm temperatures and/or sunshine (mostly size 1-2, a couple size 2.5 or 3). East of Kaslo, a naturally triggered size 2.5 windslab was reported on a north aspect in the alpine.Â
Snowpack Summary
5-10 cm of new snow and possibly thin windslabs in the alpine. Refrozen crust on all aspects up to 2200 m, softening in the afternoon at low elevations, and on steep, sunny slopes. Recent warm temperatures, sun, and rain have made the top 5-15 cm of the snowpack moist.
30 to 75 cm below the snow surface, you'll find a frozen sun crust on solar aspects. This layer was buried in early March, and it was a cause of several avalanches last week, but the recent warm weather seems to have helped this layer heal.Â
The lower snowpack is generally strong and well bonded.
Terrain and Travel
- If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.
- Be alert to conditions that change with elevation.
- When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
- Avoid steep slopes when air temperatures are warm, it is raining, or solar radiation is strong.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Avalanche Problems
Wind Slabs
Westerly winds are expected to continue redistributing available snow into wind slabs in lee features in the alpine and treeline.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2
Loose Wet
Freezing levels are falling overnight, but the surface snow may not solidly refreeze. Loose wet avalanches have been most common on steep, sunny slopes.
Paying close attention to how thick and supportive the surface crust is throughout the day, and sticking to shady slopes if the sun is packing a punch are good ways to avoid any wet loose avalanche problems.
Aspects: South East, South, South West, West.
Elevations: All elevations.
Likelihood: Unlikely - Possible
Expected Size: 1 - 2