Observation: Turnagain

Location: Sunburst

Date:
Observer:
Route & General Observations

We skinned up to 3150′ and dug a pit near the ridgeline on a SW aspect. The snow in the upper 4′ of the snowpack was right side up, and there was 4-6″ low density snow from the past 24 hrs. No major signs of instability, but there were enough signs of recent loading to keep us off the steeper slopes.

With mostly sunny skies, we got a good look at recent activity from the past week. We saw recent avalanches in just about every gully in the Library, all along Seattle Ridge, below the Sunburst Ridge, and on N and W aspects of Magnum. These avalanches varied in size, but most were plenty large enough to bury a person and some propagated a few hundred feet wide. Nothing appeared to have failed deeper than the storm snow interface. We saw multiple fresh cornice falls in the area.

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

Light snow under cloudy skies at the parking lot this morning. Skies cleared as we climbed, and we enjoyed mostly sunny skies for most of the day. Wind was calm all day.

Snow surface

4-6" low density snow from the past 24 hours, sitting on top of the snow from the 1/6-1/11 storm event. Visible signs of recent wind loading at upper elevatioins, both on Sunburst and in the surrounding area.

Snowpack

1200': Total snow depth was 9.5', with 5' settled snow since 1/4. The 12/1 crust was buried 6.5' deep, and was very hard to get a probe through.

2000': Total snow depth was 11.5', with 5.5' settled snow since 1/4 and 7' snow on top of the 12/1 crust.

3150': We dug on a SW aspect on a slope that looked like it had seen some loading (most likely yesterday morning). Total snowpack was about 9.5' deep, but we only dug down about 4' deep. We did not get any alarming test results, with a handful of ECTN's (10, 16, 20) on various storm snow interfaces, and a handful of CT's (10, 18, 21, 22, 26) on similar layers. All of the CT's were Q2-Q3.

Signs were pointing to good stability. BUT, we were still careful with our terrain selection after so much snow in the past week, and clear signs of recent wind loading in the past day. There is still plenty of soft snow in the top 2' of the snowpack that will be easily moved around even with moderate winds.

Photos & Video
Please upload photos below. Maximum of 5 megabytes per image. Click here for help on resizing images. If you are having trouble uploading please email images separately to staff.