Observation: Mary Ellen

Observation Date
12/26/2016
Observer Name
Sean ZW

Region:

Location Name or Route
Mary Ellen Gulch (Upper AF)
Weather
Sky
Few
Wind Direction
West
Wind Speed
Light
Weather Comments
Beautiful day with clearing skies and cold temps. The winds had backed off considerably after sunrise and it was quite pleasant in the sunshine off the ridge lines. Lots of diamond dust stellars in the air gave extra depth to the etherial light. Convective clouds by 2pm rolling across the valleys in the upper terrain of AF.
Snow Characteristics
New Snow Depth
12"
New Snow Density
Low
Snow Surface Conditions
Powder
Wind Crust
Snow Characteristics Comments
A diverse selection of snow surfaces dotted the landscape today. Wind scalloped open terrain above 10K, especially in bowl like terrain features of upper AF canyon. Mid elevation, sheltered terrain on all aspects skied well. Supportable base from the early part of the storm with 30cm of new snow in the last 24 hours. Stellar crystals of the ultra fluff variety made up the top 3cms of the snowpack.
Red Flags
Red Flags
Recent Avalanches
Heavy Snowfall
Wind Loading
Poor Snowpack Structure
Red Flags Comments
The new snow was bonded well in places without wind input and slabbed up anywhere else. Some notable sluffs on steep northerly terrain and small natural cycle were observed. Also saw small windslabs running on crust on SE facing slopes in MEG.
Avalanche Problem #1
Type
Wind Slab
Trend
Same
Problem #1 Comments
The evidence of wind transport across the multiple drainages we visited was evident. The bowls were circulating the wind currents and rippling many snow surfaces. Confirmed small skier triggered windslabs on steeper SE facing terrain where windslabs had bonded poorly to underlying sun crusts from before the storm.
Avalanche Problem #2
Type
Persistent Slab
Trend
Same
Problem #2 Comments
This is certainly a concern in the upper northerly reaches. We are only a week out from the Birthday Chutes avalanche and ensuing night rescue. That memory keeps me skeptical of any windloaded slopes in the alpine. We have added another 2" of H20 in most of the central Wasatch and with continued wind transport we will see that weight possibly doubled in certain locations. The sleeping giants may come to life in isolated terrain features where November snow is still lingering.
Comments
Photos: 1.Upper MEG with small windslabs visible on SE facing terrain off ridge lines. 2.Suncrust buried up to 30cm on southerly slopes. 3.The diamond dust was everywhere
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate
Snow Profile Coordinates