A gradual cooling trend with forecast precipitation, should bring snow to the alpine and then slowly to lower elevations. Persistent weak layers continue to be a concern for large destructive avalanches.
Summary
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
Light precipitation combined with moderate southwest winds and freezing levels slowly dropping from 2000 metres overnight. Light precipitation, light easterly winds, and freezing levels between 1200-1700 metres on Thursday. On Friday, light to moderate precipitation with moderate southerly winds, and freezing levels slowly dropping. A chance of broken skies on Saturday with moderate southwest winds and freezing levels around 1500 metres.
Avalanche Summary
No new avalanches reported. On Sunday, a size 3 persistent slab avalanche was triggered naturally in the Birkenhead Lake area. The aspect and elevation are unknown; however, the mid-January surface hoar was the likely culprit. This speaks to the ongoing touchy persistent slab problem in the north of the region. On the same day, 2 people were partially buried and 1 person was fully buried in a size 2.5 slab avalanche on a south-facing alpine feature in Marriott Basin. The exact failure plane of the slide was unknown, but warming was thought to have played a major role in initiating the human triggered avalanche. Hats off to everybody who pulled-off a successful rescue. Check out the great Mountain Information post for more details. On Monday, widespread loose wet avalanche activity to size 3 was observed in steep, sun-exposed terrain. The gradual cooling trend will make heat-induced surface avalanches less likely; however, very large persistent slab avalanches are still possible in the north of the region.
Snowpack Summary
Thin new crusts have formed on most aspects above moist snow, and above dry snow on northerly aspects. New surface hoar has been reported from the Coquihalla area. Cornices are reported to be huge and collapse has become more likely with daytime warming. About 50-80cm below the surface, you'll likely find a rain crust which formed on January 28th. This crust is widespread and exists up to about 1900m. Previous wet and heavy storms have likely flushed out the deeper mid-January surface hoar in the south of the region; however, this weakness which lies between 60 and 130cm below the surface is still reactive at higher elevations in the Duffey, Hurley and Birkenhead areas. This layer continues to produce sudden results in snowpack tests and has been responsible for recent destructive avalanches.
triley,
Avalanche Canada
