Avalanche

Snowshed Mtn

Lydia and MichaelFlathead Range & Glacier NP
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Quick report

Cracking
isolated

Our skis and boots experienced all four seasons in a single day: 4" of fresh snow at upper elevations,  gusty ridgelines, slushy snow near the exit, and a brief hike out on dry ground . 

  • Instability Assessments: We dug on northerly slopes at mid and upper elevations with no propagation results in pit tests.  1 recent slab avalanche on a windloaded and rocky slope in upper elevations. 
  • While lower elevations received .5" of wet snow this morning, above 5800' had up to 4" fresh snow. Lower elevations had very wet surface snow on the exit. Skinning on steeper, sun exposed slopes was difficult due to sliding on the supportative melt-freeze crust.
  • We found recent wind loading on old cornices and up to 7" wind slabs (4F) in isolated locations.
  • There was minimal loose wet evidence visible from the weekend.

This was our first day as field partners, so we stuck to simple terrain and had clear discussions at decision points like before entering avalanche terrain, before we skied, and near wind loaded ridges.

Cracking occured in wind slabs on previously formed cornices ( up to 2') and radial cracking under skis on wind loaded slopes.

Weather

Cloud Cover
broken
Wind Loading
moderate
Rain Elevation
5600
Recent Snowfall
10
Snow Avail For Transport
small smounts

Experienced the spring mixer today - white rain at trailhead, moderate gusts transporting snow at upper elevations, breaks of sunshine through mostly cloudy skies, graupel and S-1 until 1200. Winds were northwesterly and westerly, with decreased gusting strength in the afternoon.

Snowpack

  • N slope at 6200'
    • HS=175cm
    • ECT21N down 10cm on new snow interface
    • Right-side up snowpack with 3" overnight snow
  • NE slope at 6650' in steep, sheltered terrain
    • HS=210cm
    • ECTN14 and ECTN13 x 2 down 14cm on melt-freeze crust (2mm thick and P)
    • See attached snowprofile.
  • NE slope at 7200' in open, slightly wind loaded location
    • HS=280cm
    • ECTN13 x 2 in top 15cm on multiple wind slab interfaces

Avalanche

Size
D2.5 R3
Type
HS
Aspect
SE
Trigger
N
Elevation
6900 ft

We saw old activity including 8 x LW up to size D1.5 and 4 x PS up to size D2.