The snowpack around Cooke City ranges from 6 to 10 feet deep. Persistent weak layers are not widespread and the pack has had time to adjust from the near record breaking snowstorm last week (photo page). Avalanche activity has been minimal the past few days; a clear indicator avalanches are becoming harder to trigger.
Alex Marienthal of the GNFAC stands on fresh debris on the north Face of Mt Blackmore. This slide originated near the ridgeline and appeared to be triggered by a cornice drop. Photo GNFAC
WET AVALANCHES: Above freezing temperatures and the potential for rain will increase the wet avalanche danger on steeper slopes. Pinwheels and point releases are signs instability. If these signs are present, move to lower angle terrain or to shadier aspects.
WET AVALANCHES: Above freezing temperatures will increase the wet avalanche danger on slopes getting full sunshine. Rolling pinwheels are a sign the snow surface is losing cohesion and wet-loose avalanches may occur.
This avalanche in Trespass Creek of the Crazies was triggered by a snowmobiler on Sunday (2/12). The dots are where two of the part were stopped when the slide roared by...about 30' away. Photo: J. Works
This human triggered avalanche occurred in Sunlight Basin in the southern Madison Range. The slope has an east-northeast aspect and was heavily wind loaded. The slide was triggered from low on the slope and it propagated a few hundred feet uphill. The rider who triggered the slide was not caught, but another rider in the run out zone was partially buried near the toe of the debris. Fortunately nobody was injured in this incident. Photo GNFAC
A snowmobiler triggered this avalanche from low on the slope. The rider who triggered the slide was not caught, but another rider parked in the run out zone was partially buried. The slide failed at the ground and deposited up to 15' of debris in the run out. Fortunately nobody was injured in this incident. Photo GNFAC
From Lucas Zukiewicz, SNOTEL guru. A history of big storm events at Fisher Creek site.
1971 – From 11/23/70 to 12/5/71 SWE at Fisher increased from 7.2” to 15.5”. 8.8” 14 day storm total.
The unique part of 1971 was the consistency of the snowfall throughout the winter. 30 day totals for each month were substantial. From 1/6/71 to 2/4/71 the SNOTEL site received 16.2” of SWE. This 30 day period saw continuous snowfall with the average daily snowfall rate being 0.5”. Certain days exceeded 1.9” of SWE.
Wet Avalanches: Above freezing temperatures will increase the wet avalanche danger on slopes getting full sunshine. Rolling pinwheels are a sign the snow surface is losing cohesion and wet-loose avalanches may occur.
This avalanche was triggered late Sunday on the backside of Daisy Pass underneath Chimney Rock. Snowboarders were returning to town on their sleds when they hit this slope. Noone was caught. Although the skies are clear and winds are calm, this avalanche reminds us that it is still dangerous out there! Photo: K. Birkeland
