Gunnison
AvalancheIrwin Guides · Jan 30, 2014 · Gunnison
Weather
Overcast and snowing all day with snowfall rates that increased from S-2 to S-5 around noon with some periods of grauple. Ridgetop winds were strong from the SW in the am, there was a brief lull mid-day, and then they increased to extreme from SW in the afternoon. Blowing snow was intense most of the day. 8†of snow (0.65†SWE) fell since 7am, bringing the total on the storm board to 14†(1.75†SWE) and the HS to 65â€Â. Temperatures at the study plot were in the mid-20s all day.
Snowpack
In protected areas, storm slabs up to 10†were reactive today on facets near a thin (3mm) rain crust that formed early in the storm. As winds picked up during the day, thicker and stiffer slabs formed on cross-loaded slopes near and above treeline. These slabs are up to 18†thick with ~6†of 4F hard snow at the surface and F snow down to the crust. In wind- and sun-protected areas, the snowpack is mostly weak and faceted below the recent storm snow. On westerly aspects near and above treeline, thin but stiff slabs lurked near the surface of the old snow. On sun-exposed slopes, a variable melt-freeze crust lies directly under the recent storm snow with a layer cake of crusts and facets below that.
Avalanche
Skiers triggered several D1 sluffs earlier in the day on west and east terrain. A SS-ASc-R1D1-S ~ 6†deep x 20’w x 60’long ran on the rain crust in on SE aspect ATL. Skiers triggered several thicker slabs, 8-10†deep on various aspects. These were all less than 20' wide and ran up to 150’.