The avalanche danger is HIGH on all aspects and elevations. Natural avalanches are likely, and human-triggered avalanches are very likely. Heavy snowfall and strong winds have created dangerous avalanche conditions, and avalanches may break several feet deep and hundreds of feet wide, running thousands of vertical feet on any number of buried weak layers in the snowpack.
For today, I will avoid being on or underneath avalanche terrain. There is plenty of great travel and good snow to be had on lower angle slopes less than 30 ° in steepness.
Strong winds have created sensitive wind drifts on all aspects in mid and upper elevation terrain. Cornices have grown large and sensitive and may break further back from ridgelines than you expect. On northerly-facing slopes, any avalanche involving wind-drifted snow may step down to a deeply-buried persistent weak layer. Avoid any wind-drifted slope.
Yesterday there were reports of cracking and collapsing within the new snow, this is a sign of unstable conditions and if you see cracking and collapsing avoid being on or underneath steep slopes. The storm snow will be reactive today failing within density inversions, or at the interface with the old snow surface. On northerly-facing slopes, any avalanche involving storm snow may step down to a deeply-buried persistent weak layer.
Photo (Mortensen) of cracking in the new snow, this is a sign of weaknesses and if you are seeing this, then avoid steep slopes (greater than 30° in steepness).
There are a number of buried weak layers in our snowpack this season, with additional snow and wind any of these layers are weak enough that they could avalanche deep enough to bury a human. We have a weak layer of sugary facets near the ground, formed in November/December and has caused many large avalanches this season. This layer is most likely to be triggered in steep, thin snowpack areas, and on repeater slopes. We have a layer of near surface facets that are now buried 2'–3.5' feet deep, formed during the cold weather at the end of January. We also have a layer of dirty graupel that is showing full propagation in extended column tests and may have facets involved. To top it off, we have a layer of buried near surface facets that is more likely to be found in mid and low elevation terrain.
What: The avalanche danger for the warning area is HIGH today.
When: In effect from 6am MST this morning to 6am MST Sunday
Where: For all the mountains of Utah and Southeast Idaho, including the Wasatch Range, Bear River Range, Uinta Mountains, Wasatch Plateau, Manti Skyline, the La Sal Mountains, the Tushar Range....
Impacts: Heavy snow and drifting by strong winds have created widespread areas of unstable snow and very dangerous avalanche conditions at all elevations. Natural and human-triggered avalanches are certain. People should avoid travel in all avalanche terrain and keep out of avalanche runouts. Avoid being on or under terrain steeper than 30 degrees.
Yesterday, there were a couple of backcountry avalanche reported to the Utah Avalanche Center from the Provo Region. Highway operations reported many avalanches. Check out all avalanches and observations HERE.
Video (Cromwich) of a natural avalanche just outside of the Aspen Grove parking lot.
Currently, under overcast skies trailhead temperatures are in the mid-teens °F and the highest peaks are in the single digits °F. Winds are blowing lightly from the southwest in the teens gusting to the 20's at the lower ridgelines and from the east in the 30's gusting to the 40's MPH at the higher ridgelines. Today, look for partly cloudy skies with continued snowfall, 1"-3" additional snow expected and .2"-.4" of water. Temperatures will be 25-30 °F and winds will blow from the west-northwest 10 gusting to 20 MPH at the lower ridgelines and 30 gusting to 45 MPH at the highest ridgelines with the off chance of gusts to the 50's MPH. Clouds and snowfall may slow down later this afternoon. Storm totals as of 5 am range from 18"-25" of snow and 3"-4.5" of water.
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This information does not apply to developed ski areas or highways where avalanche control is normally done. This forecast is from the U.S.D.A. Forest Service, which is solely responsible for its content. This forecast describes general avalanche conditions and local variations always occur.
