Cornices
N
NE
E
SE
S
SW
W
NW
- Alpine
- Treeline
- Below treeline
- Likelihood
- Unlikely - Possible
- Size
- 1–3
Several cornice failures were observed in the past 48 hours and some of these did trigger storm slabs on the slopes below up to size 2.
Avalanche forecast
View on mapJasper
Apr 12 – 13, 2013Parks Canada
Archived · expired 13 years ago
Avalanche danger
Sun
Mon
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
Highlights
Significant snowfall is expected for the Columbia Icefield area - conservative terrain choices are advised until the snow has a chance to stabilize.
Avalanche problems
Storm Slabs
NNEESESSWWNW- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 1–3
The primary concern is where new storm slabs are sitting on previous crusts,in which case they may be triggered by light loads. Existing windslabs on lee aspects will also become more sensitive to triggering with the increased load from the new snow.
Weather Forecast
Weather models show the Columbia Icefield area receiving steady snowfall for the weekend, with up to 25cm total by Sunday night. Winds should remain light SW below 2000m, but will be gusting in the strong range (SW-NW) in the alpine. Temps remaining cool and freezing levels below 1300m.
Snowpack Summary
Windslabs on lee aspects (NE) of exposed ridgecrests above treeline are covered by 5-10cm of new snow. New snow is sitting on previous temperature crusts below 2100m and on sun crust on solar aspects. Cornices are big and heavy, and several natural cornice falls have been observed in the past few days. Melt freeze crust carries well in AM.
Avalanche Summary
No new avalanches observed today, but several large cornice failures reported in the past 48hrs. Of note, several of these cornice falls did trigger deep persistent slabs with crown fracture depths of up to 1m, and some were observed to have triggered more recent storm/wind slabs with a depth of 10-40cm.
Confidence
Intensity of incoming weather systems is uncertain