Sea To Sky

Wind slabs at upper elevations remain a concern. Don't let improving conditions tempt you into unsupported terrain.

Moderate -

Thursday: Cloudy with sunny periods. Winds light from the southwest. Freezing level around 800 metres with alpine temperatures of -9. Friday: A mix of sun and cloud with isolated flurries bringing a trace of new snow. Winds light from the southeast. Freezing level to 700 metres with alpine temperatures of -9. Saturday: Cloudy with sunny periods and isolated flurries bringing a trace of new snow. Winds light to moderate from the west. Freezing level to 600 metres with alpine temperatures of -9.

Reports from Tuesday include observations of a natural cornice release triggering a Size 2.5 wind slab avalanche near the Pemberton Icefield. Ski cutting in the Whistler area also produced several Size 1 wind slab releases. Much like the previous day, numerous loose snow point releases were again observed running naturally from steep solar aspects during the afternoon.For Thursday, lingering wind slabs are the main concern. Look for these in the immediate lee of exposed terrain features, and particularly on northerly aspects.

At higher elevations, the widespread mid-February melt-freeze crust is now typically down 20-40 cm. This crust extends as high as 2200 m and is up to 15 cm thick at treeline. The recent storm snow is reported to be bonding well to the crust, but professionals in areas with deeper storm snow amounts are being cautious with this assumption. Reports from Monday also suggest that the storm snow is now faceting with the current cold temperatures and that new surface hoar is forming. Recent cornice failures have been reported on high northerly aspects but cornices are generally expected to have gained considerable strength over the past couple days of cold temperatures. Wind slabs at higher elevations are expected to diminish in reactivity over the coming days, but should be treated with continued caution while the potential for human triggering still exists.