PATROL LOG-MEDICINE BOW NORDIC SKI PATROL
Kevin Chamberlain

Sunday, March 26, 2000:

Snowy Range-Green Rocks and Potholes corridor
        35°F, very windy, snowing at 10:45, sunny in afternoon

Vehicle count:  10:40 am
Visitor Center  1       sm
lower Barber Lk Road    2       sk
side road near CM       5       
Corner Mountain 0       
Little Laramie parking area     2       sm
Sand Lake road  0       
turnout 0       
road below Barber lk rd 18      16 sm, 2 sk
Barber Lk rd to Green R 40      32 sm, 8 sk
Green R to Snowy L      28      20 sm, 8 sk
Snowy Lodge     7       sk

snowstake:  42 in

Ski tour:
Green Rocks trailhead north along Potholes corridor approximately
2/3rds of the way to Brooklyn lake.  Stopped for lunch and snowpit
in SE1/4 SE1/4 Sec 11, 10360¹.  Skied back along same trail.  1/2
to 1 inch of fresh snow on soft snow-baked crust in the trees, with
wet, spring conditions in open areas.  Difficult to ski especially
in the open areas as the snow was very fast but the crust broke
randomly.

It is with great sadness that I must report that the Potholes corridor
has been discovered and used by snowmobilers.  Over the distance I skied,
the trail was tracked by at least two and possibly 4 wide-track
snowmobiles, on all but two small sections of the trail.  There is only
about 1/4 mile total that is untracked.  The resulting ruts are 1/2 to a
foot deep and make this trail hazardous to ski until at least a foot of
new snow has accumulated.  It will be especially hazardous with only a
few inches of snow as the ruts may be hidden but dangerous.  The day the
snowmobilers used the trail was relatively warm and the ruts had frozen
firmly overnight.  The perseverance of this party must be noted, there
were several areas where they squeezed their machines through rubbing
trees on both sides.

While on patrol a report was filed at the Visitor¹s center of snowmobiles
using the lower Libby Creek trail.  A party of campers heard and saw the
snowmobilers travelling from the Barber Lake trail onto the lower Libby
Creek several times during the weekend.  It must be assumed that deep
ruts exist in that trail also and that it is hazardous for skiing.

Snow pit:
Location:  SE1/4 SE1/4 Sec 11 T16N R79W, along 15¹ tall ridge
Elevation:  ~10360'
Orientation:  E facing open slope, leeward with thick forest above
Dip:  18 °
Depth:  5'7"  (172 cm)
Description from top down:      Temperatures:  OA 35 °F
        0-2cm:          fresh snow, fist indentation    
        2-8cm:          suncrust, icy, 1 finger 
        8-27cm: fine (0.5mm) loosely consolidated        20cm  33 °F
                crystals, fist   
        27-30cm:        coarser xtals (1mm), 3 finger           
        30-31cm ice layer, pencil               
        31-65cm consolidated xtals (1 mm) 2 finger       40cm  31 °F
                         60cm  31 °F
        65-79cm xtal clusters (1-2mm), 4 finger         
        79-88cm coarse, polygonal xtals (2-4mm),
                loosely consolidated, fist       80cm  32 °F
        88-110cm        consolidated slab (1mm), 2 finger       100cm 33 °F
        110-117cm       loose xtal clusters (2mm xtals, 6mm
                clusters), fist 
        117-139cm       coarse, consolidated slab, 2mm xtals,
                2 finger        120cm 33 °F
        139-172cm:      TG depth hoar, 2-3mm facetted crystals, 140cm 34 °F
                well-formed trapezoids, loose, fist     160cm 35 °F
                        
Modified shear test using skis: no shear induced.  
Shovel shear test:  failed at 8, 25, 65 and 110 cm with moderate to heavy force

Summary:  slope is relatively safe and snowpack is relatively stable
despite several soft layers within it.  With continued warm temperatures
expect the pack to strengthen even more.