A storm is forecated overnight but snowfall amounts are uncertain. If fsnowfalls are significant i.e. >10cm we can expect avalanche danger to return to Considerable. Cloudy skies are forecast so the solar influence should be minimal on Monday.
Summary
Confidence
Moderate - Intensity of incoming weather systems is uncertain on Monday
Weather Forecast
Forecast models differ. One says we may see up to 15cm of snow from an upslope storm coming through the region while the other says only a few cm's. If we do get the higher amounts forecasted we can expect avalanche danger to return to considerable at treeline and above! Winds are forecast to increase out of the Sw into the moderate range overnight with a freezing level near 1900m.
Avalanche Summary
A few loose wet slides up to sz 1 were observed later in the day on Sunday.
Snowpack Summary
In the am, the surface crust was holding together pretty well with overnight lows of -10C at 2200m. This crust is up to 20cm on solar aspects but it was fully broken down on these aspects by later in the day due to the solar radiation. Expect to encounter a melt freeze crust on all aspects up to 2200m then the only place you wont find the crust will be on true north aspects. The base of the snowpack still consists of weak facetted crystals that are the foundation of the stronger upper snowpack layers. Thin shallow snowpack areas remain the most likely places to trigger a failure in these basal crystals that may propagate out into deeper areas. Solar radiation is having a strong influence on the stability right now. Expect stability to decrease as temperatures warm up throughout the day. These decreases will be most apparent on solar aspects especially where the snowpack is shallow. Cornices are also large and have been failing with the heat so be sure to keep and eye on these features.
mike.koppang,
Alberta Parks
