Alud

Avalanche Alley, Fish Lake, Southern Wallowas

Caleb MerrillSouthern Wallowas
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Quick report

Wet and sloppy summarize our travel from Clear Creek up to about 6000'.  Limited visibility from snow and clouds limited our observations of other natural avalanches.  We received 3-4" of new snow during our ride.  There was good quality riding on slopes less than 30 degrees above 6,000'.   I know we keep beating this drum, but it's not the time to push it out there.  Keep wide terrain margins as our snowpack hopefully starts to heal.... If you want a more stable snowpack, go to the Blues.  

2 Recent Large avalanches were observed. Inconsistent test results (ECTX, CTV, CT20SP). Poor snowpack structure was observed.

Weather

Air Temp
32
Cloud Cover
obscured
Wind Loading
none
Rain Elevation
5000
Recent Snowfall
10-15
Snow Avail For Transport
moderate amounts

We started out at the snopark with 36 degree temperatures and rain. Rain transistioned to snow around 5000'. Throughout the day we received 10-15 cm of new snow above 6,000'. Forecasted winds were not apparent at our elevation of travel (up to 6800').

Snowpack

Two large natural avalanches and recent reports of others (Simmons Ridge) in the Southern Wallowas is all the bulls-eye data we need to know we are dealing with an angry dragon.  We conducted a crown profile of the Avalanche Alley recent natural, and found a total snowpack depth of 200 cm/6.5' and an average crown height of 120 cm/4 feet of snow ranging from F+ to Pencil hard snow sitting on a layer of facets that was buried on January 4th.   We conducted some snowpack tests at or near the crown.  CTV (column failed on Isolation).  CT20SP down 120cm.  ECTX (No Propagation), and PST40/125(end) down 120cm. PST 50/125 down 125cm.  The collapsing and cracking that has been observed in this zone was not noted today- meaning you may not get as many obvious clues to the instability below you.   Let this not make you complacent, as the potential for triggering a large deadly avalanche is very real.  Areas to avoid would be thin, rocky spots within the snowpack.  This is where we believe you could awaken the dragon. 

We did note other failures within the upper snowpack- mostly on density changes and preserved lighter-density snow.  Triggering an avalanche in one of these upper layers could easily put enough weight on our house of cards to trigger a deeper and more destructive avalanche.  

Avalanche

Size
D2.5 R4
Type
SS
Aspect
NE
Trigger
N
Elevation
6800 ft

We observed two large natural avalanches in our travels around Fish Lake today. We had very limited visibility, and suspect that there were more natural avalanches that we could not see. The first avalanche ran across FS Rd. 66, putting 3+ feet of debris on the road, and the debris terminated in the creek below the road. The crown height averaged 4 feet deep, and the avalanche failed on small grained (1-1.5 mm) facets that sat above a thin crust. SS-N-R4-D2.5-O. While riding around fish lake, we observed the terminus of avalanche debris hitting lake elevation. We could not see the crown.