Significant snowfall overnight, has added a new load to an already weak snowpack. The additional weight of a rider will likely result in an avalanche, breaking into layers of weak snow in the lower snowpack. Smart terrain choices are prudent today, especially in areas you know old sugary snow exists, under the new snow.
New snow (13") recorded at the Schneider Meadows snotel overnight, will make for touchy storm slabs for at least the next 24 hours. These slabs will not be specific to slope aspect, but rather any slope greater than 30 degrees is potentially dangerous. Storm slabs will generally stabilize after a 24-hour period.
The weak snow sitting on top of a stout crust, will get a run for its money over the next few days. Adding the weight of a rider, increases the probability of triggering a dangerous persistent slab avalanche. You must dig down to determine if a crust, with weak sugar snow on top is present in the area you're riding. If you find this combination, choose simpler terrain or avoid avalanche terrain. This can be a difficult problem to manage and terrain is our best way of handling this problem.
We found all the ingredients of a persistent slab avalanche sandwich in the Southern Wallowas last weekend at 7,000'. An avalanche sandwich consists of strong snow (think crust) weak snow in the middle (sugar snow) and more strong snow on top (new snow/wind slab). You add the weight of a rider and you are going to test this weak combo. The average skier/snowboarder can potentially trigger this weak layer even when it's buried 3' beneath the surface. A snowmobiler upwards of 8'. It's important to understand how the North America Avalanche Danger scale works.
