If the wind picks up on Thursday, treat danger as CONSIDERABLE and expect to find reactive wind slabs.
Cold exposure is a major concern for backcountry travelers (read more in this blog).
Winds have shifted to the north and may be forming fresh, reactive slabs in a reverse-loading pattern and at lower elevations than is typical.
A weak layer down 80 to 150 cm is suspected to have been the culprit of recent large avalanches in the region. This layer may take a few days to adjust to the new snow load. Avoid thin, shallow areas where triggering is more likely.
On Tuesday, operators reported numerous natural, human, and explosive-triggered storm slab avalanches, up to size 3 on north and east aspects in the alpine and treeline.
Last Saturday, natural persistent slab avalanches were reported to size 3 in the Whistler backcountry.
Looking forward to Thursday, backcountry travelers should watch for evidence of wind transport and be cautious in wind-loaded areas.
30 to 50 cm of recent storm snow overlies wind-affected surface in exposed areas and in sheltered areas a weak layer of surface hoar.
A melt-freeze crust is found down 60 to 80 cm and becomes thin and variable above 1900 m.
Another crust from early Dec is down 80-150 cm. A few large avalanches observed in the region on January 6 are suspected to have failed on this layer.
Snowpack depths are 120-230 cm around treeline and decrease rapidly below.
Wednesday Night
Mainly cloudy with isolated flurries. Northerly winds 30 to 70 km/h. Treeline temperatures drop to -10 C.
Thursday
A mix of sun and cloud with isolated flurries. Northerly winds 20 to 40 km/h. Treeline temperatures drop to -18 C.
Friday
Sunny with no new snow. Northerly winds 20 to 50 km/h. Treeline temperatures drop to -23 C.
Saturday
Sunny with no new snow. Northerly winds 15 to 30 km/h. Treeline temperatures around -20 C.
More details can be found in the Mountain Weather Forecast.
