Observation: Turnagain

Location: Turnagain Pass

Route & General Observations

Broken sky cover with low fog/clouds in and out. WARM. Temps in the upper 30’s
at 1000′ and upper 20’s at the Sunburst weather station 3800′ (finally got the
data coming in at Sunburst but the webcam is still having some issues). Wind was
light from the east.

There were several older natural slabs that pulled out mid-storm on 3/29. Mostly
in the small to medium category, 8-12″ crowns in the usual places.

Surface conditions:
2″ of low density snow overnight on top of 8″ of settled 3/29 storm snow. Sun
and warm temperatures was really getting to the snow surface. By 3pm southerly
aspects damp (I’d expect a crust tomorrow morning).

Signs of instability:
-Recent avalanches (see photos)
Natural slab avalanche occurring mid-day on east facing Seattle Ridge.
Possibly triggered by a chunk of a cross-loaded cornice falling.
Human triggered slab on Tincan Proper.
Human and natural triggered damp snow sluffs in top 2″. These were running
on slopes >38 degrees.
-Minor cracking
-No collapsing

-Snow pit results:
Dug several test pits in Sunburst area (2,800-3,800′) to monitor 3/29 storm
snow bonding. One out of 5 test pits showed concerning results – ECTP11 35cm
down just below two thin crusts in faceted snow (SW aspect 3,000′). This was in
a wind loaded area. The wind slab had bonded to the thin crust below creating a
situation where the weak faceted snow under a few thin crusts was the weak layer.
Note: all other pits has stubborn failures just below the 3/29 snow, typical for
wind slab the day after wind with new snow.

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.