Snowy Range-Green Rocks and Centennial Ridge: 20°F, windy, sunny at 11:45
 

Vehicle count:          11:45 am                    2 pm
Visitor Center                7 (4 sm, 3 sk)
lower Barber Lk Road          0               
Corner Mountain               8 sk      
Little Laramie parking area   8 (5 sm, 3 sk)          28 total below Sand lk rd
Sand Lake road                4  sk      
lower turnout                 7  sm      
upper turnout                 3  sm      
road below Barber lk rd       41 (38 sm, 3 sk)
Green Rocks                   51 (34 sm, 17 sk&lodge) 102 total above Sand lk rd

Ski tour:
Forest Service road across from Centennial Visitors Center up Mullen Creek to Percy Park (crest of Centennial Ridge).  Followed recent skier's tracks; encountered 4 snowmobilers on FS rd.  Dug pit ~50 ft below crest in top flat of Question Mark clearing.  Skied back on same trail.  3 hours from CVC to Percy Park, 1 hour back.  Percy Park is accessible by snowmachine.  Tim Gilbert was skiing Libby Creek Trail and Sally Creek.  We were able to communicate by radio from Green Rocks to Mullen Creek and Tim was able to receive at Skinny Dip Meadow on Sally Creek but unable to transmit on either Spruce or Pole Mt. repeaters.
 

Snow pit:
Time:  3:30 pm
Location:  SW1/4 NE1/4 NW1/4 Sec 9 T15N R78W,  open
Elevation:  ~9560'
Orientation:  E facing open slope ~50 ft below crest, possibly in wind deposition zone
Slope Angle:  25° at pit, slope ~30° elsewhere
Depth:  82"  (208 cm)
Description from top down:      Temperatures:  OA 18 °F
        0-20cm:         compacted fresh snow, 3-4 finger                20cm 21 °F      
        20-22cm:        sun crust locally, 2mm xtals, pencil            
        22-140cm:       hard slab, 1mm linked xtals.  Cross-bedding     40cm 25 °F
                        visible in deposition but uniformly hard.       60cm 27 °F
                        Grain size increases towards base.  1-f to p.   80cm 30 °F
                                                                       100cm 31 °F     
                                                                       120cm 32 °F
        140-208cm:      consolidated TG, 2mm facets, hard until 140cm 32 °F
                        broken through.  1f-pencil      
                        

Shovel shear test:  moderate shear at suncrust (20 cm), rest of slab solid no shear.
    Did not free block deep enough to test TG-slab adhesion, but believe it would
    require a major trigger to break the slab free in this location.

Summary:  This pit is only applicable to the upper, wind loaded portion of the
    Question Mark run.  Locally the slab is stable, although a loose snow slide
    may be possible on steeper slopes.  This is some of the hardest snow I've
    dug through-a climax slide involving this slab would likely produce injury
    just from the snow pack itself, and be exhausting to dig through.  Tim dug
    a pit in the Libby Creek valley and reported 12" new snow on a 12"
    consolidated slab with ~17" of depth hoar at the base.  Easy shear
    at the new snow/slab layer, difficult to break off the slab, but it
    broke in a large cohesive block when it failed.  Overall, I'd rate
    the avalanche risk as moderate, but higher on steep and windloaded
    slopes.  A major trigger or the presence of destabilizing rock bands
    could lead to dramatic slab releases.  In light of the slide at
    Berthoud Pass this weekend, caution is still advisable until the
    snow pack starts to warm up and homogenize.