1 Feb 03, 8:00 - 15:30, Snowy Range.  Helped with the instruction in a
Level-I Avalanche field day conducted by Dan McCoy, of UW's Outdoor
Adventure Program.  There were 12 students and 3 mock rescue sites,
followed by an afternoon of probeline practice, snowpit evaluation,
and transceiver searches.  Also helping were Neil Mathison and Frank
Davis.  Dug many snowpits.  The following is representative:

Location: Barber Lake Trail between 2 termini of Libby Creek Trail
          Zone 13 398405E 4577589N (NAD 27)
Aspect:   South, shady
Slope:    25-30 degrees

0  cm   --------- Surface --------------------------------------

        powder; hardness = fist

13 cm   --------- Old surface ----------------------------------

        coherent slab; hardness = fist

55 cm   --------- Top of depth hoar; easy shovel shear ---------

        depth hoar; loose, faceted crystals > 2 mm

95 cm   --------- Ground ---------------------------------------

A rutschblock test caused the entire slab above the depth hoar to
slide when a skier stood on the block with both skis.

Interpretation:  This snowpack exhibited all of the classic ingredients
of early-winter slab avalanches in the Rockies:  a relatively shallow
snowpack, a coherent slab, a significant underlying weak layer, and
a tendency for the slab to slide with a mild trigger.