South Columbia

Conditions are generally safe, but there are still isolated hazards from cornices and wind slabs. Check out the newest forecaster blog as you plan your spring objectives.

THURSDAY NIGHT: Cloudy with starry breaks, light northeast-east wind, treeline temperatures dropping to -16 C.

FRIDAY: Mix of sun and cloud, isolated flurries with trace amounts of snow, light northeast wind, treeline temperatures warm to -6 C.

SATURDAY: Mostly sunny, light wind from the north, treeline temperatures warm to -3 C.

SUNDAY: Sunny, increasing southwest wind, treeline temperatures warm to 0 C

A few large cornice failures (size 2) were reported on Monday and Tuesday, and a skier-triggered size 3 cornice reported Wednesday in Rogers Pass. There were also a few small (size 1) human-triggered wind slab avalanches in alpine terrain (see photos of this remotely-triggered wind slab from Wednesday).

At treeline and above up to 20 cm recent snow covers a crust on all aspects to 2200 m and up to mountain tops on solar aspects. Recent northeast wind has formed wind slabs on lee aspects below ridgetops and left a variety of wind affected surfaces. Another prominent crust layer is found 40-80 cm deep.

Cornices are very large and exposure to slopes beneath them should be minimized, especially if the weather is sunny, warm, or windy.

• Pay attention to cornices and give them a wide berth when traveling on or below ridges.
• Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.