Observation: Maybird Gulch

Observation Date
3/17/2018
Observer Name
Greg Gagne
Region
Salt Lake » Little Cottonwood Canyon » Maybird Gulch
Location Name or Route
Maybird Gulch
Weather
Sky
Overcast
Precipitation
Moderate Snowfall
Wind Direction
West
Wind Speed
Moderate
Weather Comments
Interesting winds. Very calm most of the while, with periods of moderate to even strong gusts with some drifting.
Snow Characteristics
New Snow Depth
12"
New Snow Density
Medium
Snow Surface Conditions
Powder
Snow Characteristics Comments

Dense storm snow totaling 30 cms (12") in Maybird above 9000'. Periods of graupel showers.

Red Flags
Red Flags
Recent Avalanches
Heavy Snowfall
Wind Loading
Cracking
Red Flags Comments
Lots of cracking in storm snow, especially in areas with any wind loading.
Avalanche Problem #1
Problem
New Snow
Trend
Decreasing Danger
Problem #1 Comments

Most noticeable hazard today was sensitivity within storm slabs. Lots of cracking, and very reactive down ~20-25 cms (8-10") in either interface with old snow, or lower-density layer within storm snow.

Avalanche Problem #2
Problem
Persistent Weak Layer
Problem #2 Comments

Didn't dig down deeply enough today to identify or assess this layer. But we've received 2-3+ inches of SWE over the past 3-4 days. A significant load over a short period of time. Only means deep slab avalanches will just be larger than before.

Comments

No detailed pits or photos from today. LOTS of hasty pits and ski cuts. In addition to weaknesses down ~20 cms, was also getting clean shears down 45-50 cms (18-20")at ~9000' just above MF crust from earlier this week. This surprised me a bit as Wednesday storm seemed to come in very warm, with rain to 9k, indicating storm snow should have bonded well.

Didn't really start paying attention to structure of the snowpack until about 8500'. Was finding 1-2 cm supportable MF crust, with damp grains beneath it above that elevation. The damp grains were not especially weak. Saw others (Trent in Cardiff) finding very weak damp/wet facets at lower elevations, so it may be more elevation dependent.

Storm snow weaknesses should settle out quickly. Would be very leery of deep slab issues given continued activity in deeper layers this past week, plus the significant loading since Wednesday.

Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate