Observation: Primrose Cirque

Observation Date
02/9/2016
Observer Name
Joey Dempster

Region:

Location Name or Route
Primrose Cirque, Timpanogos
Weather
Sky
Clear
Weather Comments
Bluebird, of course. Very warm in the sun, air temp around 40 at Aspen Grove at noon.
Snow Characteristics
Snow Surface Conditions
Powder
Wind Crust
Melt-Freeze Crust
Damp
Snow Characteristics Comments

If you didn't like the snow today, just move over 20 feet.  There was a little bit of everything.  Dense settled powder, lots of wind deposition, hard surfaces up high that invoked fear of a "slide for life" for the first time this season, avalanche debris, and breakable crust.

Red Flags
Red Flags
Rapid Warming
Red Flags Comments
Ol' Reliable, aka Robert's Horn, started going off at 11 as usual. It appeared that it had already spat out the biggest avalanches that it was capable of in the first days of the warming trend, and now it's just smaller slides that aren't running past the obvious deposition zones. Stay off of the debris after about 10:30 and you aren't likely to be in the line of fire. However, that debris provides the annual golden road to the top in the morning before it becomes active, with all weak snow having been pulverized and cleared out by the roaring wet slides of the last few days.
Avalanche Problem #1
Type
Wind Slab
Problem #1 Comments

There was ample wind deposited snow above 8000 feet, mostly on North facing gully and ridge sides.  Textbook cross-loading of such features could be observed all the way up the cirque, and had to be cross several times.  All of the ones that my party tested, ski cut, skinned across, and flat-out skied were welded in place.  A few very shallow, very small pieces cracked out and slid, but nothing of consequence.  They were probably more recently formed, and had little depth or mass.  The major deposition is a week old and isn't budging.  However, in the steepest and most consequential spots, we gave the wind pillows a wide berth.  No reason to test the ones that were most likely to be exceptions to today's rule of general stability.  If you were going to find trouble today, it would have been with a wind slab.

Comments

In the Falls Couloir (above 2nd Falls), off to the side, I measured 235cm (almost 6 feet) of snow on the ground!  I think this was on the high side, but in general, the snow is deep and stable in wind sheltered areas on timp.  Stability tests in this area did not budge (ECTX and CPST 80/90 with a collapse but 0 movement).  Columns, as they have been for a couple of weeks in all of my tests, can't even be pried off of the old january facet bed surfaces that were causing problems a few weeks ago.  I'm still mindful of that layer, but I'm about to put it to bed mentally for good after another few days of nice weather.  It just isn't showing any signs of weakness at this point.  

The hazard I observed today was generally low, all the way to 10,000 feet, with the exception of the obviously loaded steep starting zones which I treated as if they were "moderate" hazard, but, as mentioned above, in the few places where we did get to ski cut this snow, it didn't budge.  So I'm going to go out on a limb and say that hazard is actually LOW at this point, at least in Primrose, and also having skied steep powder in Snake Creek on Monday with no signs of instability either in shovel tests or ski tests.  If there is a potentially active deeply buried weak layer left in the snowpack, I haven't seen it in a week of looking very hard.

Today's Observed Danger Rating
Low
Tomorrows Estimated Danger Rating
Low
Snow Profile Coordinates