Date: 03/26/2021
Name: Jack Caprio
Zone: Crested Butte Backcountry
Consistent moisture throughout the week rewarded us with many pow days in the snow-favored areas of the zone. Check out the weekly summary to see how these storms impacted avalanche conditions.
Date of Observation: 03/27/2021
Name: Andrew Breibart
Zone: Southeast Mountains
Location: Washington Gulch-Coneys
Aspect: North East, East
Elevation: BTL
Avalanches: NA-poor visibility
Weather: Obscured skies with S1 and S2 snowfall. Calm. On the skin out, obstructed skies, calm and intermittent S-1 snowfall.
Snowpack: Supportive snowpack valley bottom to the ridge. 48-hour snow: 3 to 6 inches with 8 inches on the leeward side of the ridge line. New snow seems to be bonding to the last melt freeze crust. Triggered shallow storm sluff at the convex entrance to first bowl.
Date of Observation: 03/26/2021
Name: billy barr
Zone: Southeast Mountains
Weather: Very light, scattered dense snow Thursday, then light snow after midnight so the 24 hour total is 4″ new and 0.24″ of water. Snowpack is at 49½”, the deepest since mid February. Calm yesterday and so far today. High yesterday 33F, low today 18, current 19. Overcast with a very light snow.
Date of Observation: 03/25/2021
Name: Evan Ross
Zone: Southeast Mountains
Location: Coneys
Aspect: North East, East
Elevation: 9,000-11,000
Weather: Mostly Cloudy. Several nice burst of snow interspersed with sun and greenhouse conditions. Calm winds.
Snowpack: About 4″ of new snow down in the valley and about 8″ near the top of Coneys. New snow was well bonded to the supportable crust below. Hand pits wouldn’t pop anything above the crust and no signs to instability. Same results at ridgeline. Old tracks form yesterday were still visible off the highest point of Coneys. The new snow was definitely feeling the heat, but man the cream sure is surfing good.
Date of Observation: 03/24/2021
Name: Ian Havlick
Zone: Southeast Mountains
Location: Snodgrass Frontside
Aspect: North, North East, East
Elevation: 10,200-11,500
Avalanches: none
Weather: BKN moved to OVC with S-1 snow showers late afternoon. no accumulation. temperartures 20-28F. Mostly calm.
Snowpack: I dug 12 full profiles today for a CU researcher BTL snodgrass, N-E aspects. No stability tests as I was collecting density data in treed terrain, but still same poor structure, P-hard slab above 20-40cm 2-4mm F+ DH. has improved a bit from same locations dug 1 month ago, F- DH then, compared to F+ DH now, but still weak, and stiffer slab. General HS in areas dug between 11, 200 and 10,000 was 90-130cm.
Date of Observation: 03/24/2021
Name: Eric Murrow
Zone: Northwest Mountains
Location: Washington Gulch – obs from near TH to treeline on Baldy
Aspect: North, North East, East, South East, South, South West, West, North West
Elevation: 9,400 – 11,900′
Avalanches: Good views midday showed no recent avalanche activity.
Weather: Partly cloudy skies, with a good amount of sunshine in this area. Snow showers developed in areas east and west of Elkton, but no snowfall from 1130 – 430. Some thunder was heard from nearby convective cells. Maybe an inch or so of new overnight in this area. Winds were variable and light – very little blowing snow observed at upper elevations.
Snowpack: Covered a lot of ground on the snowmachine looking at sunny slopes. Most sunny terrain SE-S-SW had moist to wet surface snow sitting on older, well-developed melt/freeze crusts. On these sunny slopes, I anticipate the incoming storm system to fall on supportive crusts without much concern for developing a Persistent Slab problem. Shoulder aspects, east and west, had a few inches of dry snow resting on soft/melf freeze crust with additional soft crusts in the upper snowpack.
Shaded slopes facing very close to due north remain dry without crusts present, but as soon as you tilt eastward crusts show up below the snowfall since Saturday night. There are two layers of interest in the upper snowpack on shaded slopes, the upper being a melt/freeze crust with 1mm facets below and the other the mid-march weak layer with 1-1.5mm facets. At one near treeline site facing northeast, HS 155, I got moderate propagating results on the mid-march weak layer. Test results grabbed my attention – triggered avalanches are possible in the upper snowpack with a similar structure.
Closer to Washington Gulch TH I checkout a north slope with a much shallower snowpack, closer to 90cm, and found a fairly weak snowpack. Just an inch or two of recent snow sits on a soft melt/freeze crust with very weak 1-2mm facets below. A poor-looking structure for future loading events.
Photos:
Date of Observation: 03/24/2021
Name: Jack Caprio
Zone: Southeast Mountains
Location: Lower Slate
Aspect: North, North East
Elevation: 9k-11k
Avalanches: Intentionally ski triggered a small persistent slab avalanche on a wind-loaded feature just off a road cut. The avalanche broke in two places: On the most recent interface about 10-15 cms down from the surface, and on the 3/10 interface which was buried about 40 cms.
Weather: Overcast and warm.
Snowpack: I stayed below treeline all day near the border of the NW and SE zones. In the protected areas where no wind loading has occurred the snowpack is very weak top to bottom. Generally, no slab avalanche concerns on protected northerly slopes due to lack of a slab in this area. As I stepped out into open skied, wind-affected areas slabs became more common. Slabs were generally soft but did reach 1F hardness just above the 3/10 interface on the slide I triggered. The 3/10 interface consists of 1-1.5 mm facets on due north slopes in this area.
Photos:
Date of Observation: 03/23/2021
Name: Alex Tiberio
Zone: Southeast Mountains
Location:
Aspect:
Elevation: 9500
Photos:
Date of Observation: 03/24/2021
Name: Eric Murrow
Zone: Northwest Mountains
Location: Kebler Pass Corridor
Aspect: North, North East, East
Elevation: Below treeline
Avalanches: no, recent avalanches observed. Spotted one old crown on SE aspect below treeline in Elk Basin.
Weather: Mostly cloudy skies with light snowfall throughout the day. Around 1 – 2 inches by morning with an additional inch during the day. Light winds below treeline.
Snowpack: Traveled across a number of east and northeast slopes below treeline that previously avalanched in early February. Around 90cm of settled snow has accumulated on bed surfaces with HS around 125cm in top of the start zone. No concerning test results found (ECTN 12 on mid-March facet/crust interface down 40cm). On an east aspect found ice columns have formed from previously meltwater draining through much of the snowpack, but still short of reaching the ground. Below 10,500 feet only the shadiest, north aspects remained dry below recent snow. Sunnier shoulder aspects have a variety of soft crusts near the surface from multiple small snows over the past week. Dust layer observed down around 6 – 8 inches in this area.
Date of Observation: 03/22/2021
Name: Evan Ross
Zone: Northwest Mountains
Location:
Aspect: North East, East, South East
Elevation: 9,500-11,500
Avalanches: No slab avalanches observed. Small debris piles from loose snow avalanches.
Weather: Clear sky in the morning, became mostly cloudy in the afternoon with periods of sun or poor vis and convective snow showers. The average calm or light winds would get a bit more gusty during the stormy periods and I’d assume they were stronger at ridgeline. Our skin track did refill between laps.
Snowpack: Last weekend’s interface was around 30cm’s deep. Given the amount of recent and now well settled snow, we found ourselves initially managing for wider spread storm slabs and more specific wind slabs. That recent snow was resting on crusts on the easterly slopes and softer or lightly fasted snow on the more shaded aspects. In the end neither avalanche problem appeared to be reactive and the past sluffs around the area also were not pulling out slabs. While confidence in the snowpack improved throughout the day, we were not about to let our guard down for the potential of an avalanche in the upper snowpack. Todays colder temps helped keep the ski quality high.
