Avalanche Forecast

Issued: Mar 25th, 2015 8:42AM

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

Peter, Avalanche Canada

Kootenay Boundary.

Warm temperatures and sunshine are the main drivers of avalanche hazard at the moment. Minimize your exposure to large slopes if the snowpack is becoming moist or wet.

Summary

Confidence

Fair

Weather Forecast

Thursday: Cloudy with sunny breaks and chance of showers. The freezing level rockets up to 2500 m, maybe even higher. Winds are light from the SW. Friday: A system is poised to cross the region late on Friday or Saturday morning. The day should start with sunny breaks and high freezing levels (3000 m). As the system crosses there will be precipitation, slightly cooler temps, and increasing SW winds. Saturday: Possible showers early, then clearing. The freezing level is near 2000-2200 m and winds are moderate from the SW.

Avalanche Summary

No new avalanches were reported on Tuesday. On Sunday and Monday a few size 1-2 storm slabs were reported from the northern part of the region. These were all from NW-NE aspects between around 2000 and 2300 m. One slide on Sunday was reported as a size 2.5 that may have been triggered by a cornice fall and appeared to release on the mid March crust.

Snowpack Summary

Light snow continues to accumulate with approximately 20-30 cm in the past several days. Fluctuating temperatures have resulted in variable snow surfaces (dry, moist, crusty) depending on aspect and elevation. Moderate SW winds have formed fresh wind slabs in lee and cross-loaded terrain at and above treeline. The mid March crust layer is now down 40-60cm. 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

Wind Slabs

Forecast southwesterly winds could redistribute any dry snow scouring windward slopes and forming fresh wind slabs in exposed lee terrain. Warm temperatures and sunshine could make these more sensitive to triggering.

Use ridges or ribs to avoid pockets of wind loaded snow.>Choose conservative lines and watch for clues of instability.>

Aspects: North, North East, East, South East.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Loose Wet

Expect loose wet slides on steep sun-exposed slopes during the day. These sluffs could gain considerable mass.

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: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Mar 26th, 2015 2:00PM