Lizard-Flathead

Winds are expected to increase, so watch for slab development on lee slopes.

Moderate - Wind speed and direction is uncertain

WEDNESDAY: Mostly cloudy, strong west winds, treeline temperatures around -17 C.THURSDAY: Cloudy with flurries starting in the afternoon, strong west winds, treeline temperatures around -15 C.FRIDAY: 10-20 cm of low-density snow, strong west winds, treeline temperatures around -15 C.

On Monday, one large (size 2) naturally-triggered avalanche was reported on a north-facing alpine feature that likely failed on the mid-December surface hoar layer. Otherwise, avalanche activity has generally quieted down as the cold weather sets in. There have been some isolated reports of whumpfs at small avalanches failing on the mid-December surface hoar layer, but in most areas the snow above this layer has not settled into a slab yet.The current forecasters' blog has additional advice on the developing persistent slab problem (click here).

Cold temperatures are preserving roughly 50 cm of low density snow from last week's storms. The snow is being deposited into harder wind slabs in exposed terrain, but remains low density in sheltered areas. The main question in the snowpack surrounds the mid-December layer sitting beneath the new snow. The layer includes crusts on south and west facing slopes and large feathery surface hoar crystals in sheltered areas at and below treeline. The distribution of the layer, as well as the properties of the snow above it, is variable. The most suspect areas are where the wind has formed stiff slabs above the layer and on slopes with preserved surface hoar. The lower snowpack is generally well settled with a thick prominent crust that was buried near the end of November.