Avalanche Forecast

Issued: Jan 28th, 2013 9:24AM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Storm Slabs.

Avalanche Canada jfloyer, Avalanche Canada

Summary

Confidence

Fair - Intensity of incoming weather is uncertain

Weather Forecast

Synopsis: Northwesterly flow will bring a series of low-intensity pulses of precipitation interspersed with short-lived periods of clear weather to the region through the forecast period. Temperatures will start out fairly cool but rise Tuesday afternoon and into Wednesday to become mild.Tuesday: Mainly dry during the day. Temperatures rising from -8C in the morning to around -4C in the afternoon. Northwesterly winds, gusting to 30km/h at ridgetop.Wednesday: Light snowfall, up to 5cm. Treeline temperatures around 0C. Northwesterly winds gusting to 50km/h at ridgetop.Thursday: Dry and bright. Temperatures rising through the day with the possibility of above zero temperatures at treeline in the afternoon. Generally light northwesterly winds.

Avalanche Summary

On Monday, there were a few, mostly loose snow avalanches on north-facing slopes at higher elevations. There was one small (size 1) human-triggered avalanche reported from 1500 m at valley bottom near a creek. I suspect this is the kind of place surface hoar (most likely the Jan 24th layer, buried 40 cm) would be well preserved. Another small human-triggered avalanche was reported from a north-facing slope in the alpine.

Snowpack Summary

HST 40 to 50 cm over Jan 24 SH/sc. HST settling into soft slab - watch on solar and SH (esp BTL). Pockety WSL N & E aspects. Jan 4 SH down 90 TL & BTL. Rime or Zr CR reported in Monashees.(Eagle Pass, MPS)

Problems

Storm Slabs

An icon showing Storm Slabs
Watch for storm snow settling into a more cohesive slab on steep southerly slopes where it covers a crust or shady sheltered slopes in open glades where it rests on surface hoar. NW winds will develop fresh wind slab on S and E facing slopes.
Whumpfing, shooting cracks and recent avalanches are all strong indicators of an unstable snowpack.>Watch open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.>Use ridges or ribs to avoid pockets of wind loaded snow.>Highmark or enter your line well below ridge crests to avoid wind loaded pillows.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 4

Valid until: Jan 29th, 2013 2:00PM