Rain and Large Pinwheels on Andesite

20 to 30 cm (8 to 12 in.) of rain-soaked snow existed on the surface on all aspects up to the summit of Andesite Peak today. Looking across at Castle and Basin Peak the rain line appeared to go much higher based on the fact that there was no snow in the trees or on the rocks. Ski kicks on test slopes or small snowballs rolled onto steeper slopes entrained large amounts of wet snow and resulted in 35 to 50cm (12 to 20 inches) wide pinwheels up to 150 cm (5 ft.) in diameter. These loose wet instabilities were very easy to trigger and widespread. Some ski width wide loose wet sluffs also occurred in response to ski cuts on steep test slopes.

Snowpit tests did reveal what used to be a layer of facets buried between 80 and 90 cm below the surface. These grains were moist and easily clumped together and looked much more rounded. Tests targeting this previously weak layer did not show any sign of instability (PST 90/100 END, ECTX, DTT 22 SC, Deep ECTN 23).

The winds were strong to gale force out of the S and SSW. Rain started again around 11:00.