Observation: Summit

Location: Fresno

Route & General Observations

Standard skin track to 2850′. Looking for recent surface hoar, checking out faceting in the snow over the crust, thickness and supportability of the crust and snowpack structure above the Halloween crust and facets.

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

Mostly overcast skies with a few sucker holes
Light snow throughout the day with only 0.5" of accumulation
Winds picked up around 1 pm blowing from NE gusting into the 20s
Temps in the single digits F.

Snow surface

Trace of new snow over 1-2" of soft faceted snow over a rain/melt-freeze crust (calling it the New Year's crust to make it easy and it was buried by the New Year's Eve snow) of variable thickness.
The crust was thin and breakable (0.5-1 cm thick) until around 1600' when coming up through alders to more wind exposed terrain. Once out in the open it varied from very thin and easy to break through skinning to very hard and not able to punch through with the handle end of the pole (4-8 cm thick). There were patches of soft facets and patches of rock hard wind crust coated with the rain crust. The steeper slopes generally had a thicker crust versus mellower slope angle. Once we dug in it became evident that there are multiple layers of crust in the upper snowpack (more on this below and see photos). It was one of the more unusual crust distributions we had seen. The combination of the wind events prior to and during the rain/warm up made for very interesting surface.
There was very small surface hoar over the faceted snow on the crust down low in the trees but we did not see it higher up. There were small facets (0.5 mm) on top of the wacky crust situation in most of terrain we traveled in with the exception being spots that were scoured to the New Year's crust.
In the Alpine the winds were already moving the available soft snow and forming small slabs that were cracking as we skied over features.
The New Year's crust situation covered in facets will be an issue when the storm rolls in tomorrow.


We dug in two locations.
Pit @ 1900', East aspect, 27° slope, HS: 90 cm. There is a 10 cm layer (down 30 cm) of well developed facets over the Halloween crust (40 cm down). However, due to the layers of crust (New Year's) and 1F to P hard snow over this set-up there were no results in stability tests.
Pit @ 2650', South aspect, 20° slope, HS: 135 cm. Multiple layers of crust (New Year's) in the upper snowpack from the rain/warm up (see photo). The facets over the Halloween crust were 55 cm down and 4F sandwiched between the crust and pencil hard snow. The facets were rounding. There were no results in stability test on this layer.
With the robust crusts in the upper snowpack it seems unlikely that avalanches could step-down to the facets over the Halloween crust.

Photos & Video
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