In partnership with: Utah Division of State Parks and Recreation, The Friends of the Utah Avalanche Center, Utah Department of Emergency Services and Homeland Security and
“keeping you on top”
December 30, 2007 7:30 am
Good morning, this is
It’ll be a
different day out there boys and girls.
Increasing westerly winds and additional snowfall pushing storm totals
to nearly 2’ in the
Active and widespread sluffing was the rule yesterday with soft slab development in the afternoon in wind affected areas. A glide avalanche (more info-encyclopedia) released in upper Broad’s Fork and one backcountry skier reported triggering a 1-2’ deep 20’ wide pocket above Lake Desolation on a steep northeast facing slope at 9500’. I would expect those to be commonplace today.
Additional snowfall, rising temperatures, and blowing winds has created an unstable upper snowpack. Naturals are likely in the upper elevations with the increasing winds and during periods of high snowfall rates. Cornice development will be impressive, and those venturing onto slopes steeper than 35 degrees will get immediate feedback from the widespread instabilities. Ski cuts and cornice drops will be very effective here. I do not expect large catastrophic avalanches today, but rather widespread sensitive soft slabs on any wind drifted slope at all elevations.
Bottom Line for the
The danger is HIGH on any wind drifted slope steeper than about 35 degrees. Natural avalanches and human triggered avalanches are likely. High precipitation rates and graupel with frontal passage will ensure a CONSIDERABLE danger even in the storm snow.
There is also an isolated MODERATE danger on steep, shady slopes facing northwest, north and northeast, above about 9,500’, where it is possible to trigger a deep, dangerous slide releasing near the ground.
We should see intermittent snowfall today prior to frontal passage, with additional bursts of snow during and after it moves through. An additional 8-12” is likely in areas favored by a west to northwest flow today. Winds will continue to blow 25-35mph along the ridgelines and shift to northwest in the early afternoon. Temperatures climb to near 20, then drop again toward the low single digits tonight. Snow should start to taper off tomorrow morning with flurries expect through the morning. Heights and temperatures rise through the early part of the week ahead of a system of wet and windy storms Thursday through the weekend.
Yesterday the Wasatch Powderbird Guides did not fly due to weather. Today if the weather allows they will be in Days, Silver,
For an avalanche education class list, updated 12/22/07, click HERE.
If you want to get this avalanche advisory e-mailed to you daily click HERE.
The UAC has temporary job openings for doing avalanche outreach in more rural areas. Click HERE for info.
UDOT highway avalanche control work info can be found HERE or by calling (801) 975-4838.
Our statewide tollfree line is 1-888-999-4019 (early morning, option 8).
For our classic text advisory click HERE.
If you’re getting out and see anything we should know about please let us know. You can leave a message at (801) 524-5304 or 1-800-662-4140, or email us at [email protected]. (Fax 801-524-6301)
The information in this advisory is from the U.S. Forest Service, which is solely responsible for its content. This advisory describes general avalanche conditions and local variations always occur.
Bruce Tremper will update this advisory by 7:30 on Monday morning.