Avalanche Forecast
Issued: Mar 23rd, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
ahanna,
Avalanche Canada
Overnight snow and wind have likely formed wind slabs in lee terrain features at upper elevations. The best riding can be found in wind sheltered areas where the new snow hasn't formed a slab.
Summary
Confidence
Weather Forecast
Disagreement between weather models has resulted in a high degree of uncertainty around how far inland the heavy precipitation associated with this storm will push. The bulk of the storm will pass Tuesday night with unsettled convective activity following behind, resulting in scattered flurries through the day Wednesday.
Tuesday night: 10 cm in Smithers and south, 20+ cm along the western border of the region and possibly hot spots in high lying areas to the east . Extreme westerly winds easing to moderate and shifting northwest. Alpine high temperatures around -6. Freezing level 1100 m.
Wednesday: 5-10 cm new snow. Moderate northwest wind. Alpine high temperatures around -7. Freezing level 1100 m.
Thursday: Mix of sun and cloud. Northwest wind increasing to strong. Alpine high temperatures around -7. Freezing level 1000 m.
Friday: Mix of sun and cloud. Strong northwest wind shifting southwest. Alpine high temperatures around -5. Freezing level 1000 m.
Avalanche Summary
Reports of avalanche activity on Monday come primarily from the southwest of the region, near the Howson range, including:
- a natural size 2 wind slab on an east aspect around 2000 m
- explosive-triggered cornices and wind slabs size 1-3
- natural loose wet avalanches out of steep rocky solar aspects
- skier triggered size 1 loose dry out of steep terrain.
Touchy storm slab conditionshave been observed since Saturday at Sinclair. Reactive wind slabs were reported in the Hudson Bay Mountain area on Friday prior to the storm.
Snowpack Summary
Recent snowfall amounts have varied widely with elevation and between ranges within the region. 20-50 cm of snow from the past week overlies hard wind affected snow at alpine elevations, potentially surface hoar crystals on sheltered north aspects, and melt-freeze crust on south aspects and below treeline. Recent observations suggest warm temperatures have aided bonding at this interface. At lower elevations, recently rain soaked, now refrozen and crusty surfaces are covered by a dusting of snow.
The mid and lower snowpack is reported as well settled and strong in most areas. However, weak facets exist at the base of the snowpack in the more shallow snowpack zones within much of the region and always have the potential of being triggered on steep, rocky slopes with a shallow or thin to thick snowpack; especially with large loads such as a cornice fall.
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Seek out sheltered terrain where new snow hasn't been wind-affected.
- Dial back your terrain choices if you are seeing more than 20 cm of new snow.
Problems
Wind Slabs
New snow and elevated southwest winds have formed new surface instabilities that vary by location in the region. Expect thicker, more widespread storm slab formation in the snowier southwest of the region and wind slabs more confined to leeward terrain at exposed elevations closer to Smithers.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 24th, 2021 4:00PM
