Public Observation

Observation Details

Signs of Unstable Snow

Observations

Observations from the Downing mountain area during the 1/31 - 2/1 storm. Monday weather was very windy, with sustained winds over 20 miles an hour and extensive transport. New snow formed moderately reactive soft slabs in many open locations above about 6,500 feet. New snow totals were up to about 20 cm. Tuesday weather was much calmer, and the total storm total was less than 30 cm at 8,000 feet.

We didn't observe any notable surface hoar or facets before the storm. The new snow was reactive to ski cutting during the storm, with moderate shooting cracks and propagation of soft storm slabs in ski cuts on steep unsupported slopes on Monday. On Tuesday, we did not note any cracking or obvious signs of instability, however we limited our terrain to moderate slope angles. Many of the soft slabs in exposed locations had stiffened into relatively unreactive hard slabs by Tuesday afternoon. We didn't observe any natural avalanches during the storm cycle, but visibility was limited.