Avalanche Data: The avalanche averaged 4’-5’ deep, about 65” at its deepest point, was 400’-500’ wide and ran 450’ vertically. Classified as a HS-AM-R4-D3-O, this avalanche failed on weak facets near the ground. While slope angles averaged 36 degrees, a steep breakover about a third of the way upslope was closer to 40 degrees. It was in this steep, rocky section where the snowpack was the weakest. The southern half of the range often experiences weaker snow and stronger winds.

Weather and Snowpack History: The western Uinta snowpack is historically plagued by cold temperatures, shallow snow depths, very weak snow and strong winds… this winter is no exception. An active weather pattern in October, deposited early season snows above 9,000’ and it looked like a banner start to the season. The storm track shifted north and the western Uinta’s were left high and dry throughout November. The first in a series of storms began moving into the region on Dec. 1st, depositing 12” of snow, followed by a slightly stronger system on Dec. 7th. New snow totals averaged 14” in the area the accident occurred and gusty southwest winds accompanied this storm. An avalanche watch was issued on the 7th describing an overall danger of CONSIDERABLE in upper elevation wind loaded terrain. Clear, cold weather following this storm allowed near surface facet development. A vigorous storm system on the 21st stacked up an additional 16” of snow and warranted issuing an avalanche warning as high winds and heavy snow created a HIGH avalanche danger on steep northerly facing slopes. A natural, albeit pockety, avalanche cycle occurred during the storm. The 22nd dawned clear and cold and with new snow on a weak pre-existing snowpack, we knew all the ingredients for an avalanche accident were aligning. Two snowmobile triggered avalanches occurred in the southern half of the range and probably many more that we didn’t hear about, but no serious incidents were reported… we dodged a bullet. Another storm rolled in on Christmas Eve delivering 8” of very light density snow, but west and northwest winds gusting in the 50’s along the ridges accompanied the system. The avalanche advisory posted on Dec. 25th called for an overall CONSIDERABLE avalanche danger on steep, upper elevation slopes and specifically mentioned there were pockets of HIGH danger on these same slopes where wind drifts were present. In addition, the advisory mentioned “the possibility of triggering a deep, scary avalanche that breaks into weak snow near the ground still exists, especially in steep, upper elevation terrain facing the north half of the compass”. Unfortunately an avalanche fatality on Christmas Day occurred near 1000 Peaks in Weber Canyon in that exact kind of terrain. Click here for that accident summary. On the 27th and 29th, two snowmobile triggered avalanches ran on facets near the ground in steep, leeward upper elevation terrain. 2007 went out with a bang as a series of storms continued to pound the region. The Uinta’s were on the storm tracks cusp and what we lacked in storm snow we made up for with wind. West and northwest winds began blowing on the evening of Dec. 29th with hourly averages in the 30’s, gusts in the mid 40’s. By the evening hours of Dec. 30, nearly a foot of new snow stacked up and winds raged in the 70’s and 80’s. A Special Avalanche Advisory was issued to warn the public of the HIGH avalanche danger. We continued the Special Advisory for Dec. 31st and most of our local media contacts advertised the increased danger for the western Uinta’s in their newscasts. I warned of “large dangerous slides, breaking into old snow near the ground, especially on steep, rocky, upper elevation slopes resulting in an unsurvivable avalanche.”