Avalanche Forecast

Issued: Mar 27th, 2015 10:26AM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Loose Wet and Wet Slabs.

ghelgeson, Avalanche Canada

Kootenay Boundary.

Warmth is the main driver of avalanche hazard at the moment. Minimize your exposure to large slopes if the snowpack is becoming moist or wet.

Summary

Confidence

Fair - Freezing levels are uncertain on Monday

Weather Forecast

Saturday: Freezing level hovering around 2000m all day. Moderate NW winds at treeline, Strong NW winds at ridgetop. Cloud cover reducing to about 40% in the late afternoon. No significant precipitation expected.Sunday: Freezing level hovering around 2000m. Light SW winds at treeline, moderate SW winds at ridgetop. Broken cloud cover, sunny breaks possible. No significant precipitation expected.Monday: Freezing level starting around 2000m, rising to 2500m by the afternoon. Calm at treeline, moderate W/SW winds at ridgetop Scattered cloud. No significant precipitation expected.

Avalanche Summary

Storm slabs ran to size 2 on all aspects Thursday as cold snow was subjected to rapidly warming temperatures. Loose wet avalanches ran on all aspects to size 2.5. The larger loose avalanches were running on north through west facing terrain between 1900m and 2100m.

Snowpack Summary

5 to 20 cm of new snow was left in the wake of Wednesday night's storm. Most (if not all) of this storm snow was affected by rain that fell to ridgetop Thursday afternoon as temperatures rose as high +4 at 2000m. This wet surface snow did not re-freeze Thursday night. The mid-March crust layer is now down 40-60cm, and possibly deeper on wind loaded features. Most recent reports suggest that the overlying snow is bonding well to the crust. However, a snowpack test on Tuesday from the northern part of the region produced an easy sudden "pops" result on a crust/facet interface down 70 cm. This was on a northwest aspect near 2200 m.

Problems

Loose Wet

Loose wet activity is expected to persist with the bulk of the activity occurring below 2000m. Periods of sun could initiate fresh rounds of loose wet activity at upper elevations too.

Be aware of party members below you that may be exposed to your sluffs.>Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Wet Slabs

Warming has added a lot of strength to the snowpack, but it may still be possible for riders to trigger a slab failing on the mid-March crust in the alpine. Strong W winds may increase the reactivity of this slab at upper elevations too.

Dig down to find and test weak layers before committing to a line.>Avoid freshly wind loaded features.>Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 4

Valid until: Mar 28th, 2015 2:00PM