We have had two days of very strong winds and wind slabs have formed in exposed upper and mid elevation terrain as well as on or around terrain features like subridges and gullies on exposed slopes off the ridgelines. Heavy snowfall today will bury existing wind slabs underneath making them hard to see. Winds are forecast to increase this afternoon and, with wind slabs building on top of wind slabs, it'll be safest to avoid steep slopes with freshly wind drifted snow and look for obvious signs of instability like cracking or collapsing. (click here to learn more about wind slabs.) Getting caught in even a small windslab could be dangerous as it could step down into older, weak snow and become bigger and more consequential.

Cornices are becoming more widespread along ridgelines and will continue to grow larger and more sensitive with today’s winds and heavy snowfall. Cornices often break back further than expected, on to what looks like flat terrain. Give them a wide berth and avoid travel below them.

Though weak layers are getting buried deeper beneath the new snow, recent triggered avalanches on buried layers of faceted snow on steep slopes show dangerous conditions exist in the Ogden area mountains. Many slopes have poor structure – soft sugary, weak layers, both mid-pack and near the ground. It seems some of the steep slopes are just waiting for a trigger, like more weight from snow and wind or a rider. It's hard to predict which slopes will slide though those facing northerly through easterly are the most likely and should be avoided, especially in continuously steep terrain or terrain with gullies, trees or cliff bands. This type of avalanche has the potential to run far down into low elevation terrain as evidenced by Wednesday's Hells Canyon slides so avoid travel under steep northwest through east facing slopes. Getting caught in this type of avalanche could be unsurvivable.

As with wind slabs, cracking and collapsing are bulls-eye clues to instability, but for persisent slabs these clues may not be present, and snow pit tests could be unreliable.

To learn more about persisent slab and other types of avalanche problems, click here.

Though not across the entire Ogden zone, areas of high snowfall intensity will create 1-2' deep storm snow avalanches very quickly during the day. The Bountiful bench has already picked up 9+ " so even travelers on low elevation trails should avoid crossing or being under steeper terrain today. With conditions changing so rapidly, the safest option is to stay of off all slopes steeper than about 30 degrees to avoid this problem.