Avalanche Forecast

Issued: Mar 25th, 2015 8:38AM

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

Peter, Avalanche Canada

South Rockies.

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 - Due to the number of field observations

Weather Forecast

Thursday: Cloudy with sunny breaks. The freezing level rockets up to 2800 m, maybe even higher. Winds are moderate from the SW. Friday: A mix of sun and cloud. The freezing level remains near 3000 m and winds are moderate increasing to strong from the SW. Saturday: Possible showers/flurries. The freezing level is near 2200 m and winds are strong from the SW.

Avalanche Summary

There are no new reports of avalanches from the region for the past couple days. However, neighbouring regions reported some loose dry slides on Tuesday and widespread natural slab avalanches to size 1.5 above 1800 m on Monday.

Snowpack Summary

Light snow continues to accumulate above 1500-1700 m. Many areas have likely received 20-30 cm in the past several days. Periods of strong W-SW winds may have redistributed the new snow in exposed high elevation terrain, creating fresh wind slabs on lee and cross-loaded slopes. Lower elevation slopes are probably moist or wet and the snowpack continued to rapidly dwindle. A weak rain crust from last weekend is down 30-50cm and generally seems to have a good bond with snow above. There are a couple older persistent weak layers in the midpack that are still intact and have the potential to wake-up with substantial warming or heavy loading. Cornices may become fragile with afternoon warming.

Problems

Wind Slabs

Forecast southwesterly winds could redistribute 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.

Highmark or enter your line well below ridge crests to avoid wind loaded pillows.>

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.

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

Deep Persistent Slabs

Rapid warming and solar radiation could make deeper persistent weaknesses more susceptible to triggering, especially and sun-exposed and thinly snow-covered slopes.

Use caution around convexities or areas with a thin or variable snowpack.>Minimize exposure to sun exposed slopes when the solar radiation is strong.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

3 - 5

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