NORDIC PATROL REPORT  -  31 Jan 98  0930-1530

    Myself and Tok (the nordic wonder dog) skied from Green Rock
trailhead to the first overlook on the Libby Creek loop where we dug a
pit. Tok is recovering from an injury and this was her first real
outing in some time and she was psyched!! Chatted with one group of 4
adults, 2 kids, and 2 dogs.  Tok and I returned to Green Rock to count
cars and meet the rest of the group.  Observed several large groups of
skiers headed up various directions.
    After connecting with my wife and a friend we skied back up the
Libby Creek loop.  Met one group on snowshoes (2 adults, 2 kids).  Made
a leisurely tour of the Libby Creek loop.  Near the road on the way out
we met two telemarkers who asked about avalanche conditions.  I told
them what I had observed, and gave the usual cautionary disclaimer.

Weather - Very nice day. NO WIND!  Air temp around 30 F.  Partly cloudy,
with a couple of very minor snow flurries.

Snow stake depth = 38 inches.

Snow pit located  below ridge crest on SE facing slope below first
overlook on Libby Creek Loop.  Picked a spot with obvious wind
loading/drifting on a 33 degree slope.  

Total depth 112 cm:

1 - 6 cm - wind crust

7 - 17 cm - Four finger hard.  Broken, slightly rounded fragments, about
.5mm in size

18 - 32 cm. Four finger hard.  Rounded, .5-1mm in size.

33 - 63 cm. Pencil hard.  Angular fragments, < .5 mm in size.

64 - 90 cm. Four finger hard.  Depth hoar.  Well developed cup crystals,
showing some rounding.  About 2 mm in size. 

91-107 cm. Four finger hard. Depth hoar. Well developed cups, 2-4 mm in
size. Not rounded.

108 - ground. Very hard to icy.  Depth hoar, 2-4 mm.  Cups are quite
rounded and strongly sintered.  Almost an ice layer, but the old cup
shapes a clearly visible.

A ski shear test (using a ski behind the column rather than a shovel)
showed a moderate shear in the depth hoar at about the 90-91 cm depth. 
Also a weak shear at the base of the surface wind crust.

General Assessment:  Moderate temperatures and increased snow depths
have reduced the temperature gradient to the point where
equi-temperature metamorphism is beginning to sinter the depth hoar. 
The middle of the depth hoar layer is still quite weak however.  Also,
note that this is a SE facing slope below tree line.  On more northerly
aspects and at higher elevations the temperature will remain colder, and
the sintering process will take longer.

Car Count:  At 1130 there were 102 vehicles at Green Rock.  They were
parked along the road nearly to the next turn out down the hill, where
there were 14 more parked.  About 85% of the vehicles had trailers.