Observation: Summit

Location: Colorado

Route & General Observations

Colorado to 2300′ on a generally east aspect

Red Flags
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Observer Comments

Moderate to intense wind transport on ridgelines noted in the AM when skies weren't obscured.

No cracking or collapsing... with plenty of opportunities for collapsing as we set the skin track, walking over alders & on thin spots near the edges of clearings/trees.

Driving south through Turnagain Pass: Visibility was limited, but we spotted a few recently opened glide cracks, and what looked to be 2 additional small glide avalanches beyond the one reported Thursday.

Weather & Snow Characteristics
Please provide details to help us determine the weather and snowpack during the time this observation took place.

Overcast skies with clouds lowering, eventually obscuring some neighboring peaks by the afternoon.
No precip, even though it looked likely to arrive for much of the day.
Light north winds, occasionally gusting moderate above 2000'.
Warm - right around freezing all day!

Snow surface

Ski penetration of 8-10" below the powerline, with 6-8" up to the trees. No wind affect on the surface along the entire route!


The Thanksgiving Crust was 18-24" down from the road to our high point of 2300'. See below for two pits - one at 1900' and one at 2300' - which were dug to compare crust structure/faceting at two different elevations.

The crust was much thicker and buried less deep at 1900', with variation in crust thickness even along the brief distance of the 1 meter pit wall. Small facets (.5mm) surrounding the crust - above and below it at 1900' - didn't show a significant difference in layer hardness when compared to the rounds above and below. No results - even on overdrive - for CTs on the T-Day crust at 1900'.

At 2300' facets were only found below the top of the Thanksgiving Crust, which was 5mm thick and firmly bonded to the slab above it. At this location, the facets were larger (.5 - 1mm) and softer (fist+), in a 3cm thick layer that had very consistent structure across the pit wall. For propagation tests, I got a ECTN result only after "extreme" overdrive (~15 extra taps with lots of force) while a PST failed to the end after just a 30cm cut length. See below for full details!

Photos & Video
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