There is a storm warning for Jasper Sunday night but the amounts are expected to be less in the Maligne area; however, the snowpack is inherently weak and untrustworthy. We expect the avalanche hazard to rise with the incoming weather system.
Strong to extreme winds can push the new snow further down the start zone than one would normally encounter. Watch for Sunday's storm increasing this problem into non-typical locations.
Sunday night's storm may exceed forecasted amounts. If that happens, expect a storm slab condition particularly in alpine locations.
The incoming storm snow will test the inherently weak Facets and Depth Hoar near ground. Avalanches initiating in the upper snowpack are likely to step down to this layer and gain significant mass.
Sunday's Icefield patrol was very poor visibility. A size 2.5 deep persistent slab just south of Marmot, as well as a couple wind slabs up to size 2 in the Churchill Slide Paths area, were observed from 93N on Saturday.
Don't forget to post avalanche observations to the MIN.
10cm of new snow over the last few days has been redistributed by strong SW winds, creating wind slabs in the alpine and into exposed tree line. A weak melt freeze crust facet combo down 25cm below 2100m is showing sudden collapse results in snow pit tests. Generally, the bottom of the snowpack is weak facets and depth hoar.
A snowfall warning has been issued for Jasper with potentially 20cm or more with strong to extreme southwesterly winds. The snowfall will taper off Monday afternoon. Weather models are showing only 10cm for the Maligne area yet one should expect this amount to be exceeded.
Detailed weather forecasts from Avalanche Canada: https://avalanche.ca/weather/forecast
