Avalanche Forecast
Issued: Mar 1st, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
trettie,
Avalanche Canada
***UPDATED***
Steer clear of freshly wind loaded features. Wind slabs are expected to remain reactive to human triggers.
Avoid thin and rocky start zones, especially in the alpine and upper treeline where deeply buried weak layers remain concerning.
There are preliminary reports of a serious avalanche incident near Invermere today. We do not currently have anymore information on this.
Summary
Confidence
Moderate
Avalanche Summary
There are preliminary reports of a serious avalanche incident near Invermere today. We do not currently have anymore information on this.
On Tuesday two skiers were caught in a size 2 avalanche on a sparsely treed northeast aspect at 2200 m. The crown was over 1 meter in places and showed concerning propagation. wind loading was a factor. Check out this MIN for more details.
Deep persistent slab avalanches continue to occur almost daily in this region. The most recent notable was a size 3 triggered by a natural cornice fall on a east aspect.
Snowpack Summary
Up to 30 cm of low density recent storm snow sits over wind affected surfaces. Expect deeper deposits on north and east facing slopes, from southwest winds.
Buried surface hoar sits 30-50 cm deep in sheltered terrain features, and a thin sun crust exists at the same depth on steep south-facing terrain.
The lower snowpack contains a number of buried weak layers such as surface hoar with variable distribution, as well as a widespread layer of large, weak basal facets and depth hoar in some areas. These weaknesses have been responsible for a number of recent very large, destructive avalanches and will continue to be a concern.
Weather Summary
Wednesday Night
Cloudy with a few centimeters of new snow expected. Moderate to strong southwest winds and a low of -12 °C at 2000 m.
Thursday
Mostly cloudy with up to 5 cm of new snow expected. Moderate westerly winds and a High of -4°C at 2000 m.
Friday
Mostly cloudy with trace amounts of new snow expected. Light southwest winds and a high of -8°C at 2000 m.
Saturday
A mix of sun and cloud with no new snow expected. Light southerly winds and a high of -8°C at 2000 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
- Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
Problems
Wind Slabs
Moderate winds and recent storm snow have built reactive slabs at higher elevations. Slabs may sit over a layer of surface hoar in sheltered terrain features, or over a sun crust on south facing slopes which may increase reactivity.
Aspects: North, North East, East, South East, South, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
The base of the snowpack remains very weak. Very large human triggered avalanches are possible at higher elevations. Avoid shallow and rocky areas, where the snowpack varies rapidly from thick to thin.
The mid and lower snowpack also contain several surface hoar layers, most prominent in the Purcells. Due to the overall weak snowpack structure, small avalanches are likely to step down to any of these deeper weak layers creating large and destructive avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 2nd, 2023 4:00PM
