With a foot of new snow on the ground, and another 2-4" forecasted throughout the day, avalanches involving new snow can be expected today. The new snow may sluff easily on steep slopes, as well as break out more widely as soft slabs, especially during periods of heavier snowfall or warming. But spring snowstorms are beautifully unpredictable, so pay attention to conditions where you are. Watch for signs of instability including avalanching, cracking in the new snow, and warming of the snow surface with possible greenhousing (where clouds trap warming). I am particularly suspicious of a possible density inversion within today's storm snow where you may find a denser slab on top of weaker, lower-density snow. This layer of lower-density snow can act as a weak layer for avalanching. Pay attention to how the snow feels - a hand pit can quickly determine if there is a density inversion where you will feel softer snow with denser snow on top.

West/northwest winds will drift snow primarily on aspects facing north, through east, and southeast, but drifting is possible on other aspects due to cross-loading and channeling of winds through terrain features. I am expecting most drifts will be found above 9000'.

Today's new snow and wind will add to the cornices that are found along many upper elevation ridgelines. Be sure to avoid traveling along or underneath corniced ridges.

Preserved surface hoar and faceted, recrystallized snow was buried on the shady terrain of the mid and upper elevations, and this layer may become reactive once again with today's storm. This layer was reactive on Cutler Ridge this past Friday (observation) [photo Bill Brandt] and again on Monday (observation). Warmer temperatures this week may have helped heal this layer, but we will need more field observations before making that call.

Persistent weak layers are especially tricky because they can be triggered remotely (that is, from a distance) or break above you. This layer is most likely found on northerly aspects above about 7000'. You will need to dig down 12-24" to identify this layer, and it may not be visually apparent. However stability tests such as compression tests and extended column tests should help identify and evaluate this layer. Too complicated? Avoid the problem by not traveling on or underneath slopes steeper than 30 degrees on northerly aspects at the mid and upper elevations.