10cm new snow fell overnight Sunday. This will make for good quality riding but will also hide previous wind slab in exposed tree line and alpine features. Natural avalanche activity may be tapering off but human triggering of large avalanches remains possible.
Previous strong to extreme southwest winds have created wind slab in the alpine and exposed tree line. These slabs will be difficult to visualize with the new 10cm of low density snow on top.
Expect sluffing of the new snow especially in steep solar terrain.
The bottom of the snow pack is inherently weak with well developed Facets and Depth Hoar. Numerous large natural and explosive triggered avalanches in the past week have run on this layer.
One size 2 wind slab that stepped down to the basal facets was observed in the alpine on Monday in the Icefields area.
Natural avalanches up to size 2.5 were observed in the Icefields region, initiating in alpine and exposed tree line features on Saturday.
Avalanche control with explosives last Wednesday resulted in numerous large avalanches both wind slab and deep persistent slab running to the bottom of the avalanche paths.
Don't forget to post avalanche observations to the MIN.
Up to 10cm overnight on Sunday added to the 30cm since February 7 in the Icefields area. Previous and present southwest winds had stripped exposed terrain in the alpine and continue to add to wind slab development in exposed tree line and alpine features. Generally the mid and bottom of the snowpack is weak facets with depth hoar at the base. Height of snow is variable from 50 to 150cm.
A surface ridge is establishing Tuesday and Wednesday. Expect a mix of sun and cloud with light northerly winds on Tuesday. Similar on Wednesday with wind increasing to moderate values from the west. A low pressure system is expected to bring light precipitation late Thursday into Friday with winds increasing to strong values from the west. Freezing level will remain at valley bottom in the Icefields area.
Detailed weather forecasts from Avalanche Canada: https://avalanche.ca/weather/forecast
