Avalanche Forecast
Issued: Jan 25th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
cmortenson,
Avalanche Canada
Gather information as you travel. Assess the bond of new snow if deposits are over 20 cm or anywhere variable easterly or southerly winds have created slab like properties. Keep in mind recent snow likely sits atop surface hoar.
Summary
Confidence
Weather Forecast
Continued cool temps and a mix of clouds, sun and isolated flurries for this week with winds shifting to easterly.
MONDAY NIGHT: Mainly clear, light to moderate southerly wind, treeline temperatures around -10 C.
TUESDAY: A mix of sun and clouds, light to moderate easterly wind, treeline temperatures around -8 C.
WEDNESDAY: A mix of sun and clouds, light to moderate southeast wind that shift to northeast, treeline temperatures around -11 C.
THURSDAY: Mainly cloudy with sun breaks, light easterly winds, treeline temperatures around -14 C.
Avalanche Summary
Isolated large avalanches have been reported to have failed during the weekend storm on recently buried surface hoar in the southeast of the region. Otherwise, no significant avalanche activity has been reported since Tuesday in the southern and central regions. Debris are still evident from these size 1-3 storm slabs (in the south of the region) and some very large (size 3-4) deep persistent slabs in the north. In the northern regions (e.g. Stewart or Ningunsaw), large explosives were able to trigger a couple of very large avalanches on deep persistent layers near the ground in the past week.
Snowpack Summary
10-20 cm of new snow fell over the weekend. If winds increase to moderate levels, anticipate fresh wind slabs may form in the immediate lee of wind affected ridge crests treeline and in the alpine. This new snow has also buried surface hoar in sheltered locations at and below treeline, which should be investigated anywhere snow fall deposits exceed 20 cm. New snow also buries a crust below 1000 m.
A total of 100-150 cm of settled snow has fallen in January, which has helped strengthen early season weak layers. Deeper layers appear to have gone inactive in the southern part of the region. However, in the northern part of the region (e.g. Bear Pass, Ningunsaw) there has still been regular avalanche activity on weak snow at the bottom of the snowpack with large loads such as explosives or cornice collapses.
Terrain and Travel
- Make observations and assess conditions continually as you travel.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
- Be aware of the potential for larger than expected storm slabs due to the presence of buried surface hoar.
- Watch your sluff: it may run faster and further than you expect.
Problems
Wind Slabs
Variable winds shifting to easterly may transport the 10-20 cm of recent snow and build fresh wind slabs in immediate lee of windy ridge crests in the alpine and at treeline.
Fresh snow deposits may be particularly reactive anywhere snow has developed slab properties over buried surface hoar, such as wind loaded lee areas. Elsewhere, loose snow avalanches (sluffs) can be expected in all steep terrain.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 26th, 2021 4:00PM
