Avalanche Forecast

The region continues to be in the storm track through the weekend.

WEDNESDAY NIGHT: Freezing level at valley bottom, strong southeast wind, 5 to 12 cm of snow expected.

THURSDAY: Overcast, freezing level rising to about 1000 m, strong west/northwest wind, 6 to 12 cm of snow expected during the day with 5 to 15 cm Thursday night.

FRIDAY: Broken cloud cover, freezing level at valley bottom, moderate to strong northwest wind, no snow expected during the day, 2 to 5 cm possible Friday night.

SATURDAY: Overcast, daytime temperature at valley bottom beginning around -15 rising to near 0 C during the day, strong southwest wind, 4 to 8 cm of snow expected during the day with 10 to 20 cm Saturday night.

Widespread whumphing was reported Tuesday which is a clear sign of an unstable snowpack. More details in this MIN report.

There was likely a widespread natural avalanche cycle on Sunday and Monday as a result of heavy loading from snow and wind.

There were numerous reports of touchy conditions on Sunday as evidenced here and here. 

There was a fatal avalanche accident in the Hasler area on Saturday. The incident occurred on a northeast aspect between 1400 and 1600 m. The avalanche was a size 2.5. The fracture line was estimated to be 50-100 cm and is suspected to have been a persistent slab avalanche running on a weak layer of surface hoar. Click here to link to a report on the incident.

The north of the region has seen little snow since Monday night, but the south of the region picked up an additional 10 to 25 cm of snow. This adds to the 40-60+cm of warm snow that fell through the weekend with strong southwest and west winds which formed reactive storm slabs and wind slabs in exposed terrain.

All the new snow in the last week has increased the load on a widespread persistent weak layer consisting of surface hoar. The layer is likely 80-120 cm deep near Renshaw and 60-100 cm deep around Torpy and further north. Reports suggest this layer is most prevalent around treeline elevations, but likely reaches into the alpine and down into the trees too. It may sit above a crust below 1600 m. The likelihood of triggering this layer has likely increased with the new load from the snowfall. The consequence of triggering this layer is high.

• Avoid all avalanche terrain during periods of heavy loading from new snow and wind.
• Only the most simple non-avalanche terrain free of overhead hazard is appropriate at this time.
• Storm slabs in motion may step down to deeper layers resulting in large avalanches.
• In times of uncertainty conservative terrain choices are our best defense.