Avalanche Forecast

Issued: Apr 10th, 2015 9:23AM

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

bcorrigan, Avalanche Canada

Northwest Inland.

Check out the Northwest Coast bulletin for information on the touchy persistent slab problem, which may also be present in parts of the inland region.If you'd like to share your observations, here, we'd love to have the input !

Summary

Confidence

Fair - Due to the number and quality of field observations

Weather Forecast

Light snow today, with the freezing level near 1200 m. Winds strong from the South West. SATURDAY: Cloudy with flurries. The freezing level will come down to 500m overnight, and rise to near 1000 m during the day. Forecast winds winds moderate from the SW.SUNDAY: Cloudy with flurries, freezing levels between 500 and 100m, winds moderate to strong from the South WestMONDAY: Much the same as the previous two days, but the freezing level may climb to 1500m during the day.

Avalanche Summary

In the past week, loose wet avalanches to size 2 were reported to have triggered slabs up to size 2.5, possibly releasing on the March 25th surface crust/ surface hoar layer. No reports of avalanches from yesterday, but one commercial operator reports that strong winds are stripping new snow down to the old crust surface and depositing it on lee slopes as windslabs.

Snowpack Summary

Moderate to strong winds are now scouring windward slopes and loading lee features. A crust with surface hoar buried on March 25th is still considered a potential problem in parts of the forecast region and has been most reactive, recently, in the north part of the region.This may come back to life with the new snow and wind loading. Cornices are now large and may collapse with increased load from the storm.

Problems

Wind Slabs

Wind slabs on lee slopes are definitely on the radar, with the potential for triggering a wind slab that might step down to the weak March 25th layer.

Use ridges or ribs to avoid pockets of wind loaded snow.>Be cautious as you transition into wind affected terrain.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Persistent Slabs

The weak March 25th layer is between 45 and 75cm deep. If triggered it could produce large destructive avalanches.

Dig down to find and test weak layers before committing to a line.>Choose conservative lines and watch for clues of instability.>Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 4

Valid until: Apr 11th, 2015 2:00PM