Seek out cold dry snow on higher elevation north and east aspects and watch for wind slabs in extreme terrain. Keep an eye on the effects of the sun, it could produce loose wet avalanches on south and west facing slopes Friday afternoon.
Confidence
Moderate - Timing or intensity of solar radiation is uncertain on Saturday
Weather Forecast
Friday offers one last day of temperatures on the cool side before the heat really comes on for the first time this season. THURSDAY NIGHT: Freezing level around 1000 m, light west/southwest wind, trace of snow possible.FRIDAY: Broken cloud cover, freezing level holding around 1000 m, light to moderate west/southwest wind, no precipitation expected.SATURDAY: Broken cloud cover, freezing level rising to 1800 m, light southwest wind, no precipitation expected.SUNDAY: Clear skies, freezing level at 2700 m, light variable wind, no precipitation expected.
Avalanche Summary
No new avalanche activity was reported on Wednesday. Explosive control produced small (size 1) slab avalanches on Tuesday. No other avalanches were reported.
Snowpack Summary
Relatively light amounts of moist snow have fallen on a variety of snow surfaces including a crust on steep southerly slopes and possibly weak surface hoar crystals on sheltered and shaded slopes. The new snow may take a little time to bond, especially on northerly aspects at higher elevations. The new snow has been formed into a hard and thick crust on south facing slopes, at least in the North Shore mountains.A layer of weak and sugary faceted grains sits on a melt-freeze crust about 50 to 120 cm deep. The layer is likely most prominent in the North Shore Mountains and on north aspects. This layer continues to be reactive in snowpack tests. The problem is not typical for the region and we expect this persistent weak layer to continue to linger.The lower snowpack is generally strong.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.