Steamboat & Flat Tops
AvalancheMax Strotbeck · Feb 6, 2024 · Steamboat & Flat Tops
Weather
Skies were scattered to broken with temperatures at or above freezing. Moderate south winds. No new snow.
Snowpack
I found a snowpack on Iron Mountain that generally ranged in height from 70-90cm on south aspects and 110-160cm on north aspects. A 2cm surface crust was present on south aspects in the morning (which had melted by mid-day) while the surface of north aspects were cold and soft. In a snowpit on a steep, open north aspect, I observed about 25cm of settled storm snow from this weekend sitting atop a buried layer of surface hoar crystals that formed prior to the storm. The mid-pack consisted of a harder 50cm slab of rounded grains that formed over January, which sat atop a layer of surface hoar crystals that were lying flat. The lower-pack which formed from the storms prior to January was faceted, and pencil to 4 finger in hardness on the hand hardness scale. An extended column test showed a failure that initiated on the surface hoar layer directly beneath the recent storm snow, but no propagation occurred (ECTN12 down 25cm on 10-15mm SH). In snowpits dug on south and southeast aspects, below the surface crust was about 15cm of settled storm snow, which sat atop a thick 5-6cm melt freeze crust on steeper aspects that formed in the latter half of January. The mid-pack was 30-40cm of 1 finger hard rounded grains (snow that fell from early to mid-January) sitting atop a thinner melt freeze crust that formed over the post-Christmas dry spell. Extended column tests did propagate on faceted crystals immediately atop this crust, but with vegetation present in both pit walls, I have low confidence that widespread propagation would occur on slopes with similar aspects/elevations. The lower pack was about 30-40cm and made up of faceted crystals and melt freeze crusts.
Avalanche
I did not observe any avalanches.