Avalanche Forecast
Issued: Mar 10th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
cgarritty,
Avalanche Canada
Start small and use terrain to your advantage as you assess the outcome of Tuesday's storm. Expect the new snow's depth and reactivity to increase as you gain elevation and move into wind-exposed areas.
Summary
Confidence
Moderate - Forecast snowfall amounts are uncertain.
Weather Forecast
Tuesday night: Cloudy with easing flurries bringing 5-10 cm of new snow. Moderate to strong west winds.
Wednesday: A mix of sun and cloud. Light to moderate northwest winds. Alpine high temperatures around -10.
Thursday: A mix of sun and cloud. Light variable winds. Alpine high temperatures around -11.
Friday: Mainly cloudy. Light northeast winds. Alpine high temperatures around -13.
Avalanche Summary
Observations of avalanche activity from Tuesday's storm are still limited, however mainly light snowfall is expected to have been overshadowed by the effect of strong winds redistributing new and recent snow into wind slabs around leeward slopes. New wind slab formations are likely to remain reactive to human triggering on Wednesday.
Snowpack Summary
15-25 cm of new snow is expected to accumulate in the region by Wednesday morning. The new snow has buried variable surfaces that include well developed surface hoar in sheltered areas, sun crusts on southerly slopes, and wind-affected surfaces.
A weak layer of surface hoar crystals and/or faceted grains may be found around 100 cm deep on northerly aspects at treeline and lower alpine elevations. For some of the region, the layer may have been destroyed by strong wind immediately before burial on February 22nd, but it may still exist in sheltered terrain features in parts of the region. In these areas, larger avalanches composed of new snow may cause isolated step down avalanche activity at this layer.
Weak faceted snow and melt-freeze crusts exist near the base of the snowpack in some of the region, particularly the eastern and northern parts. This layer is considered dormant, as it hasn't produced an avalanche since February 20th. This layer may require a very large load, such as a cornice fall, or rapid weather changes to reactivate.
Terrain and Travel
- Be carefull around freshly wind loaded features.
- Minimize exposure to sun-exposed slopes when the solar radiation is strong.
Problems
Wind Slabs
Light new snow amounts and strong to extreme winds have been forming new wind slabs in leeward terrain. Fresh slabs are likely to be sensitive to human triggering on Wednesday and may be found well below ridgetops and into exposed lower elevations.
Aspects: North, North East, East, South East, North West.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Mar 11th, 2020 5:00PM
