Avalanche Forecast Kootenay Boundary

Date Issued: Valid Until:

Avalanche Canada shorton, Avalanche Canada

Avalanche Forecast

Mon Mar. 11th ยท 3:01PM

Alpine

Danger Ratings Considerable

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low

Problems

Storm Slabs Storm Slabs

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low
Danger will increase on Tuesday as a storm passes through the region.

Confidence

Moderate - Forecast snowfall amounts are uncertain

Weather Forecast

MONDAY NIGHT: Storm arriving overnight with 10-15 cm of snow, 30-50 km/h southwest wind, alpine temperatures drop to -10 C.TUESDAY: Snow continues throughout the day with another 5-10 cm bringing total accumulation to 15-25 cm, 20-40 km/h southwest wind, alpine high temperatures near -5 C, freezing level 1000 m.WEDNESDAY: Lingering flurries with localized accumulations of 5 cm, light northwest wind, alpine high temperatures near -8 C, freezing level 1000 m.THURSDAY: Sunny with cloudy periods, light southwest wind, alpine high temperatures near -5 C, freezing level 1200 m.

Avalanche Summary

A few small loose dry avalanches were reported over the weekend. One large (size 3) slab avalanche was triggered remotely on a southwest aspect on Sunday. The avalanche failed on a crust layer 20-30 cm deep, but showed surprisingly wide propagation.

Snowpack Summary

Expect 15-25 cm of new snow on Tuesday accompanied with strong southwest wind. Several crust layers have formed on south aspects in the past few weeks, while other aspects have a mix of hard wind-affected snow or soft faceted snow. Two layers of weak surface hoar crystals are buried in the snowpack between 40 and 80 cm deep, which were buried in mid-February and early-February. The layers may be associated with a melt-freeze crust on southerly aspects. Avalanche activity on these layers has tapered, but it may still be possible to trigger one of these layers in isolated areas such as steep cutblocks and large open glades.

Problems

Storm Slabs

Storm Slabs

Fresh slabs will form at higher elevations as snow accumulates throughout the day.

Be careful with wind loaded pockets Be aware of how much snow is accumulating through the day and how it is bonding to old snow below.Watch for signs of instability such as whumpfing or cracking.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Possible

Expected Size

1 - 2