Ad
Observation Date: 
05/3/2018
Observer Name: 
B
Region: 
Salt Lake
Location Name or Route: 
Catherines Area: Rocky Points/Sunset
Weather
Sky: 
Broken
Precipitation: 
Light Snowfall
Wind Direction: 
North
Wind Speed: 
Moderate
Weather Comments: 
Early morning start with the skies initially clear, and then by 0930 the clouds began to fill in. Tempertures rose rapidly, and even with the skies broken the intense May sun combined with mid 30's at the 9500 plus to dampen even the northerly facing aspects with slope angles <30 degrees by 1030. Easterly and southerly aspects had roller balls as early as 0900. By 0900 the moderate NW winds veered more to be out of the direct N, and wind blown and or transport was moderate and observed on mid slope features as well as at the upper ridgelines. At 1130 there was a quick squall that moved through dropping a trace of graupel.
Snow Characteristics
New Snow Depth: 
8"
New Snow Density: 
Medium
Snow Surface Conditions: 
Powder
Dense Loose
Wind Crust
Melt-Freeze Crust
Damp
Snow Characteristics Comments: 

The 2 to 4 inches of snow that fell on Tuesday was very dense and appeared to have fallen as damp grains and served as a great spongy base. Then the PI ramped up around 1700 on Tuesday evening, and continued with S2 rates until 2000 and dropped another 5 to 8 inches of medium density snow, with another brief shot in the early morning hours. HST ranged from 5 to 10 inches depending on location and elevation with the upper BCC zone in the Catherine Basin area getting the Lion's Share. The riding was good in dense spring powder and even some of the snow that got damp rode well in the upper elevations. Lower elevations were getting sticky on the low angle by 1100.

The previously cited winds were creating upslope and cross loaded soft/shallow wind slabs. Minimal cracking in these wind slabs were observed; and by the end of the morning hours variable riding conditions were being created. North and NW facing slopes in the upper alpine were getting striped in many locations. and all aspects were getting damp besides due N wit angles 30 degrees and greater. 

Red Flags
Red Flags: 
Recent Avalanches
Wind Loading
Cracking
Rapid Warming
Poor Snowpack Structure
Red Flags Comments: 
Poor snowpack structure limited to density changes in the new snow. Hand shears were indicating an obvious easy weakness at the interface from the dense snow from Tuesday to the lighter density snow that fell later in the day. See picture below of wet loose avalanche that made efforts at propagaing to a wet slab on an easterly facing slope, and the bed surface for this small natural was the above cited interface. Minimal cracking in mostly unreactive shallow/soft wind slabs. Wind loading was occurring and the highest elevations with a possibility of wind slabs that may have been more sensitive in the afternoon hours once they were receiving more intense solar.
Avalanche Problem #1
Type: 
Storm Slab
Trend: 
Decreasing Danger
Problem #1 Comments: 

See above for the previously cited problem interface, and with the warm tempertures on Wednesday, this problem interface may have yielded more activity in the afternoon hours. The winds appeared to be serving as a contributing factor enhancing this storm slab issue in many locations in the exposed upper alpine. All that said, once the temperatures cool off later in the day and through the evening these problem issues most likely will decrease and or vanish by Thursday. 

Avalanche Problem #2
Type: 
Loose Wet Snow
Trend: 
Decreasing Danger
Problem #2 Comments: 

Widespread wet loose activity and roller balls observed from 0900 on. Of note, a group of skiers riding the steep easterly facing terrain in the Rocky Points area were easily triggering small wet loose slides. As the sun moved around the compass this issue obviously appeared to travel with it into the afternoon hours. 

See picture below, and in particular the right flank of this small wet loose. This slide tried to propagate into a wet slab, but the slope angle let up. This slide occurred at 1045 and was on an easterly aspect at 9800 feet and was initiated by roller balls coming off the rocks above it. 

 

Today's Observed Danger Rating: 
Moderate
Tomorrows Estimated Danger Rating: 
Low
Snow Profile Coordinates: 
Ad

Support the Avalanche Center through your purchases

Discount lift tickets
All proceeds from ticket sales benefit the UAC when you purchase your next lift tickets.
Lift tickets available in November
Need new gear?
Make your next purchase from our Affiliate Partners and the UAC will receive a portion of the sales.
Shop
Sign up for our newsletters, emails and daily forecasts to stay up to date.
Subscribe