Ad
The National Forest Service Logo
icon-add Observation
Forecasts
Logan Ogden Salt Lake Provo Uintas Skyline Moab Abajos Weather Archives How to read the forecast
Observations & Avalanches
Submit Observation Observations Explorer All Observations Avalanches Fatalities Weather Place Names Map Archives
Education
Avalanche Class List UAC Class List Online Classes Resources and Tutorials Avalanche Awareness Develop Skills
Events
Store
About
Contact Who we are Core Values Staff Board of Directors Past Forecasters Sponsors Annual Reports Sign In
Blog
icon-add Observation
Donate / Join

Observation: Mineral Basin

Observation Date
3/6/2019
Observer Name
B
Region
Salt Lake » Little Cottonwood Canyon » Snowbird Ski Resort » Mineral Basin
Location Name or Route
Lower Mineral Basin
Weather
Sky
Overcast
Precipitation
Light Snowfall
Wind Direction
Southwest
Wind Speed
Moderate
Weather Comments
Moderate SW winds in the am shifting to W in the pm. Transport moderate. Temperatures spring like and warm. S-1 snowfall throughout the day ramping up at 1200 to S2. Accumulations difficult to measure due to warm snowpack and temperatures, yet it appeared that at least 2 inches fell during the day.
Snow Characteristics
New Snow Depth
4"
New Snow Density
High
Snow Surface Conditions
Powder
Melt-Freeze Crust
Damp
Snow Characteristics Comments
Traveled from 9200 to 9700 on SW, SE, N, NE and NW aspects. Shady aspects had thick/dense inverted riding, yet it was decent turning besides being a bit slow. New snow constituted a 4 finger slab resting on DF/decomposing stellars. New snow was not wet/damp at these upper elevations, yet below about 8500 feet the snow surface was damp/wet and the lower you got the worse it got. An extremely wet day out there reflective of NW weather patterns. Aspects on the lower half of the compass indicated the minimal amounts of new snow (2 to 4 inches tops) and this was resting on a variety of m/f crusts with varying thicknesses.
Red Flags
Red Flags
Recent Avalanches
Heavy Snowfall
Wind Loading
Cracking
Rapid Warming
Poor Snowpack Structure
Red Flags Comments
Poor snowpack structure in the upper 10 to 40 cm layers. The most pronounced weakness was the above described Storm Slab issues related to the new snow resting on lighter density snow from previous storms this past week. This weakness was mostly stubborn and unreactive early in the day, but by later in the day it was beginning to show signs of minimal cracking. On slopes with angles approaching 40 degrees this weakness was more apparent and reactive. Mid pack weak layers yielding easy shears at 30 and 40 cm down on protected shady aspects. Widespread wet loose below 8000 feet, see observation from Y Couloir. S2 snowfall abated for a brief period during late afternoon and began again around 2100.
Avalanche Problem #1
Problem
New Snow
Trend
Increasing Danger
Problem #1 Comments
Storm Slab and Wind Slab problems were growing during the day at mid and upper elevations, and appeared to be escalating by late in the day. Additional new snow and water will only exacerbate this issue for Thursday. See above for weak structure descriptors.
Graupel Pooling an additional concern as a weak layer below steep slopes at transitional points.
The seasonal spring like warmth may help reduce the reactivity of these buried weak layers (inverted layers), yet the large amounts of water continue to be a red flag for potential avalanching.
Avalanche Problem #2
Problem
Cornice
Trend
Increasing Danger
Problem #2 Comments
Already suspect cornices continue to build and present real issues for potential for releasing naturally, and subsequently triggering large dangerous slides in steep terrain below. This issue confined predominantly to NNW, N and NE at upper elevations.
Considerable appearred likely at upper elevations for wind slabs and storm slabs. Moderate at mid elevations, and the widespread loose wet cycle at lower elevations indicated Considerable.
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable