Medicine Bow Nordic Ski Patrol
Patrol Log: Sunday, January 27, 2002:  Howell
On Sunday Jan. 27 Bob Howell (along with Jim, Aleida, and Chet Weger) skied the Potholes 
route up to the Brooklyn Lake road, then back.  In places along the trail in the open slopes 
just above Green Rock the snow is almost gone, but the conditions are good once you get 
into the trees.  We met four other skiers along the trail.


I dug a snow pit at NAD27 13T 0396765 4580004, at elevation 10440 ft on one of the 
open slopes near the upper part of the trail.  This was a 20 deg. slope facing 108 deg (ESE).  
The air temperature was -5C, with mostly clear sky, and moderate winds.  The snow depth was 104 cm.



 #  Height Temp   Layer comments Hardness   Snow grain structure
     (cm)   (C)
----104 -----------------------------------------------------
 8                 wind slab    1 finger   0.5 mm rounded
----100 --- -6  -------------------------------------------
 7                              4 fingers  0.3 mm somewhat faceted
---- 94 ----------------------------------------------------
 6   90     -8                  1 finger   0.3 mm rounded
---- 87 ----------------------------------------------------
 5   80     -7                  2 fingers  0.5 mm rounded
---- 73 ----------------------------------------------------
     70     -6
 4   60     -5                  1 finger   0.7 mm rounded
---- 56 -----------------------------------------------------
     50     -4                  3 finger   1.5 mm rounded
 3   40     -3
---- 32 -----------------------------------------------------
     30     -3
 2   20     -2                  3 finger   1.5 mm rounded
     10     -1
----  3 -----------------------------------------------------
 1                 ice          pencil     3 mm but very well bonded (ice)
----  0 ---  0 ----------------------------------------------


General comments:
  The bottom layer, despite the large crystals, was very well bonded and hard --
  ice rather than depth hoar.  There was a real but subtle boundary between the
  similar layers #2 and #3 at 32 cm.  Most of the pack seemed reasonable well bonded,
  with the exception of layer 7, just below the thin #8 wind slab.


  The wind slab was thin enough not to be a serious hazard at this location, but
  with more snow on top either the weak #7 layer or the top of the wind slab could
  be a potential failure surface.  The other two soft layers (#3 and #2) were better
  bonded than this #7.


Shovel shear test.  Working down through the pack:
  Moderate force for failure at 100 cm ( top of layer #7)
  Moderate force for failure at  73 cm (top of layer  #4)
  Moderate force for failure at  56 cm (top of layer  #3)
  Large    force for failure at   3 cm (top of ice layer #1)


With the Rutschblock test it took repeated jumps to produce a failure at 100 cm.
After that slid, additional repeated HARD jumps produced a failure at 73 cm.



The car counts were as follows.
Note -- this breaks down the counts into smaller regions, as requested on
the new count forms from the Snowy Range Winter Use Group.


                         ------- 9 AM -------     ------ 4:14 PM ----
                            with    without        with    without
                          trailers  trailers     trailers  trailers
 Corner Mountain Lot         0         1             0        0
 Little Laramie Lot          0         0             0        1


 Below Barber Lk Rd         16         1            16        0
 B. Lk Rd to Cattleguard    10         0             2        0
 Cattleguard to Turnaround  27         3            11        3
 Green Rock Picnic Gnd. Lot  0         4             0        3
 P. G. to Snowy Range Lodge  8         3             3        2


 Total                      61        12            32        9



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Page last modified January 31, 2002
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