Date of Observation: 03/11/2023
Name: Zach Guy
Zone: Southeast Mountains
Route Description: Whetstone, Gibson Ridge, and Emmons viewed from Mt. CB
Observed avalanche activity: Yes
Avalanches: A handful of D1.5 to D2 storm slabs at all elevations. Had decent visibility and did not see anything that stepped down deeper from Whetstone to Axtell to Emmons.
Date of Observation: 03/11/2023
Name: Zach Guy and Zach Kinler
Zone: Southeast Mountains
Route Description: Avalanche mitigation on the small slopes above the ice rink and nordic hill. NE-E aspects at 9,000′.
Observed avalanche activity: Yes
Avalanches: 3 storm slabs ran naturally on the Nordic Hill earlier this morning, about a foot deep. Remotely triggered a drifted storm slab from 20 feet away that was almost 2 feet deep. It broke on precip particles just above the storm interface (windboard). Numerous roof avalanches in town.
Weather: Heavy snowfall rates this morning, light winds.
Snowpack: About 18″ of top-heavy storm snow produced localized cracking in wind-protected terrain (up to 8′ long). Slabs were noticeably thicker and more reactive in drifted terrain, where I got a collapse, shooting cracks, and a remote trigger. All instabilities were on low-density precip particles that fell near the start of the storm (non-PWL).
Date of Observation: 03/11/2023
Name: Billy Barr
Zone: Southeast Mountains
Route Description: Gothic Townsite
Observed avalanche activity: No
Avalanches:
Weather: Obscured clouds and heavy, very dense snow from Friday afternoon on with 20½ inches new and water an absurd 2.19″. Wind became very strong overnight. It remains obscured with moderate to heavy snow with strong wind. The snowpack is at 79½”, winters deepest. billy
Snowpack:
Date of Observation: 03/11/2023
Name: Eric Murrow
Zone: Northwest Mountains
Route Description: Lap up Mount Emmons and snowmobile ride out the Kebler corridor to Horse Ranch Park. Traveled between 1130 and 330pm.
Observed avalanche activity: Yes
Avalanches: I was able to trigger a small avalanche on a drifted feature above treeline into Redwell Basin. Storm totals at this time were around 7 inches and the drifted slab was around 10 inches.
Weather: Consistent snowfall during the afternoon. Snowfall rates of 1 inch per hour or greater. Southwest wind blew at moderate speeds with strong gusts while I was above treeline in the early afternoon. While at the valley bottom later in the afternoon wind speeds appeared to be ramping up. Snowfall totals reached close to 10 inches at 330pm with higher-than-normal densities.
Snowpack: I traveled around simply watching the storm develop, but not enough snow had accumulated by 330 for much to happen. Small Wind Slabs developed by the early afternoon, but sheltered areas had yet to gather enough storm snow to cause much of a problem. I suspect that shortly after I left the mountains storm totals began to increase enough, due to heavy snowfall rates, that shallow Storm Slabs began forming in sheltered areas as well. A Shovel Tilt Test showed a slight density change at the bottom of the storm snow in a location with 8 inches.
Date of Observation: 03/10/2023
Name: Zach Guy
Zone: Southeast Mountains
Route Description: Mount Emmons, various aspects near and below treeline.
Observed avalanche activity: Yes
Avalanches: Skier triggered a handful of small loose snow avalanches involving the new snow; the longest ran about 1000’ vert.
Weather: S1 to S2 throughout the day. Calm winds where we traveled.
Snowpack: The new snow was not bonding well to old surfaces (sun crusts, wind board, NSF). Storm totals ranged from about 8” or 9” NTL to 6” at valley floor by 4 pm. The snow was cohesionless and sluffing, no cracking or slabbing yet.
Date of Observation: 03/10/2023
Name: Mark Robbins
Zone: Northwest Mountains
Route Description: amr ziggins, big, east bowl
Observed avalanche activity: Yes
Avalanches: old debris at bottom of big chute under the steep roll on the right hand side. Also old debris at bottom of ziggins, I skied in the trees so didn’t identify where it had come from. Maybe from the right handrail of the ziggins gully?
No storm instabilities on the first two laps. On the last lap around 3:30 things seemed to be reaching a bit of a tipping point, the storm snow sluffing more actively with some clean fractures, tho no real propagation
Weather: warm and wet. 3-4 inches of heavy snow when I arrived at 1, another solid 3 inches on the sled 3 hours later. Calm throughout the amr tenure, some gusts on the ridge
Snowpack:
Date of Observation: 03/07/2023
Name: Mark Robbind
Zone: Northwest Mountains
Route Description: Playground
Observed avalanche activity: Yes
Avalanches: See photo.
Weather: Air temp surprisingly cool, didn’t get uncomfortably warm
Snowpack: Unsupportive sun crust on southerlies in the morning. Dry snow with very manageable wind affect near and below tree line north-northeast
Photos:
Date of Observation: 03/08/2023
Name: Evan Ross
Zone: Northwest Mountains
Route Description: Green Lake area. Below Mt Axtell
Observed avalanche activity: Yes
Avalanches: The Cornice above Green Lake Bowl on Mt Axtell released sometime between yesterday and 9am this morning. I’d assume someone would have seen it yesterday afternoon if it was there. The resulting avalanche was very large in size. The fish in Green Lake were sloshed, but not displaced. The snowpack below the cornice was mostly cleaned out to the ground. However notably there wasn’t a slab avalanche that propagated any wider than where the cornice fell. The cornice above this slope was massive previous to this avalanche.
Weather: Overcast and fairly warm temps. Light winds below 11,000ft.
Photos:
Date of Observation: 03/07/2023
Name: Eric Murrow
Zone: Southeast Mountains
Route Description: Lower Brush Creek
Observed avalanche activity: No
Avalanches: nothing new observed
Weather: Thin high clouds reduced throughout the day. Mild air temps above the freezing mark. Moderate SW winds with some strong gusts.
Snowpack: Traveled through below treeline slopes close to valley bottom with depths ranging from 70cm on south up to 120cm on northerly aspects. Southerly aspects have thick melt/freeze crusts at the surface that soften and lost support to skis but remained intact preventing Wet Loose avalanches concerns from developing. On south and southeast slopes melt water has yet to reach the ground (did not dig on southwest). I was surprised to get moderate propagating test results at two locations on northeast-facing terrain (see images). Early season facets at the base of the snowpack remain weak with just enough slab cohesion for propagation.
Date of Observation: 03/06/2023
Name: Ben Pritchett
Zone: Southeast Mountains
Route Description: Cement Creek to Crystal Creek through Upper Taylor River to Taylor Pass.
Observed avalanche activity: Yes
Avalanches: Only a few cornice collapses, some which trundles vehicles size blocks. In one area near Star Pass the cornice chunks cracked a tiny D1 slab immediately below, but it did not propagate beyond the cornice collapse area.
Weather: Nice day, Southwest winds increased in the afternoon just enough to move snow along ridges. Valley bottom temperatures reached around 40 degrees
Snowpack: The March 3-4 wind event ravaged this area, scouring and sublimating snow surfaces in the alpine. The winds drifted snow deep into the treeline, forming discontinuous pencil-hard slabs in below-treeline meadows and behind wind-breaks near treeline.
Height of snow in wind-sheltered near treeline locations generally ranged from 140 to 180cm. We measured snow in the alpine generally around 150 to 170cm, but well over 300cm in drifts, with bare ground on ridges after the wind event.
We saw inconsistent new wind-slab formation in start zones, with scoured textures below many cornices adjacent to pockets of pencil hard drifts (mostly wind-eroded old drifts). These drifts proved unreactive, with no cracking seen through 50+ miles of terrain covered. The drifts were too hard to impact with snowpack tests.
Below 11,000′, snow surfaces wetted on southerly-facing terrain. We experienced a couple very localized collapses (with no visible cracking) where water percolated down to the mid-February crusts. Water was pooled on top of the uppermost crusts, around 30cm below the snow surface.
Photos:
