Avalanche Forecast
Issued: Nov 24th, 2019 3:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
cgarritty,
Avalanche Canada
Venture cautiously as you investigate the outcome of the storm. Use this forecast as an initial assessment and gather information as you travel.
Remember to post your observations to the Mountain Information Network!
Summary
Confidence
Low - Uncertainty is due to the limited number of field observations.
Weather Forecast
Sunday night: Isolated flurries bringing a trace to 5 cm of new snow. Moderate northwest winds.
Monday: A mix of sun and cloud. Light to moderate northwest winds. Alpine high temperatures around -7.
Tuesday: Mainly sunny. Light to moderate northeast winds increasing over the day. Alpine high temperatures around -9, cooling over the day.
Wednesday: Sunny. Moderate northeast winds. Alpine high temperatures around -15.
Avalanche Summary
Observations from the succession of storms that impacted the region have yet to come in, but it is expected that the significant load of new snow (along with strong winds) promoted widespread natural storm slab avalanches at elevations where snow accumulated instead of rain.
Looking forward, clearing weather is likely to make travel in the mountains a more inviting prospect, however this is a time to be on high alert in any areas where new snow buried a smooth surface. Concern is reduced in areas where the new snow hasn't yet overcome the depth of ground roughness.
Snowpack Summary
No post-storm observations have yet been reported, but it is expected that heavy rain over Friday and Saturday gave us light new snow amounts below the alpine as temperatures cooled while possibly adding a metre or more of new snow to alpine areas - thereby tripling recently observed snowpack depths at higher elevations.Â
A heavy coastal focus was noted in precipitation amounts, with 157 mm of rain recorded at Shames and only 36 mm at Rosswood.
Beyond the sheer quantity of new load in more coastal alpine areas, the bond between the new snow and the melt-freeze crust on the previous surface is expected to be poor, particularly in areas that did not experience rain in advance of the recent snowfall (higher elevations).
Problems
Storm Slabs
Heavy snowfall has likely formed thick storm slabs in the alpine that may remain reactive over the near term. A poor bond is expected between the new snow and the old snow surface. Picking out where the new snow sits on a smooth surface and where it is anchored in place by ground roughness may be tricky.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Nov 25th, 2019 5:00PM
