Incoming snow and northwest winds will build fresh wind slabs today. You are most likely to find these slabs of wind-deposited snow on east through south-facing slopes above treeline. Look for dune-like formations, textured snow, and smooth hollow sounding drifts. If you see snow like this, go down in elevation or switch aspects to avoid triggering an avalanche.
Northwest winds will build wind slabs on Northeast through South facing slopes today. It's possible to find these wind slabs on other aspects as well, as mountain topography changes the wind. Lingering older wind slabs may be found on North and West aspects from earlier this week. All aspects have some type of crust than can serve as a bed surface for these avalanches to run on.
Consistent snowfall, fluctuating temperatures and rain in some areas have created storm slabs near and below treeline. There are lots of density changes and crusts that make finding and triggering a storm slab avalanche possible. If you find slabby snow sitting on top of a crust or lower-density snow, chose slopes less than 30 degrees.
Since Tuesday afternoon, the mountains have received 6-12" of new snow. The Blues, Elkhorns, and Southern Wallowas picked up more snow during this storm with snow totals close to 1'. The Northern Wallowas received less, closer to 6". Despite the differences in snowfall totals, the overall weather patterns and snowpack changes have been similar.
As we near the end of March the snow is more wet and warm. Daytime temperatures are higher and even brief appearances from the sun can change the snow surface. These conditions have resulted in an upper snowpack layered with small density changes and crusts. These crusts can create good bed surfaces for avalanches to run on and can sandwich snow creating weak layers, as found here.
As temperatures increase and if the sun pokes through the clouds the chance of wet loose avalanches increases. This avalanche problem is a consistent possibility in spring. Stay alert to changes in temperature and the effect of the spring sun.
