Persistent Slabs
N
NE
E
SE
S
SW
W
NW
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 2–3
Recent wind loading will make this problem more likely today.
Avalanche forecast
View on mapCooke City
Gallatin NF Avalanche Center
Avalanche danger
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
Out of date — this forecast expired 8 months ago. You’re viewing past conditions, not the current bulletin.
Highlights
The mountains near Cooke City continue to get the most snow which means weak layers near the ground are getting the most stress. There wasn’t enough visibility yesterday to see if any wind slab or persistent slab avalanches were happening, but they probably were.
With widespread drifting, and more snow and more wind coming today, dangerous avalanche conditions continue. Ride slopes less than 30 degrees in steepness and avoid being under steeper slopes.
Avalanche problems
Wind Slabs
NNEESESSWWNW- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 1–1.5
Drifts can be found at all elevations with more drifting happening today.
Avalanche Discussion
Hurricane force winds ripped across the landscape yesterday toppling trees and knocking out power in places. For the snowpack, these winds drifted snow across all elevations. More winds are coming today.
Even though it didn’t snow a ton, that dense snow combined with drifting added weight to the snowpack especially on wind loaded slopes. That extra weight means more stress on weak, faceted layers near the ground. Ian says it well in his video from Cooke yesterday (full ob here). Stress on that weak snow means the persistent slab avalanche problem remains a serious concern.
At low elevations (except near Cooke City), the snowpack became wet during recent warm weather and during some rain yesterday. It should be solidly refrozen this morning, and the occasional wind slab will be the only thing to look out for.
The challenge today will be finding slopes sheltered from the wind. Watch out for and avoid fresh drifts and wind slabs that can avalanche. The wild card is old faceted snow near the ground that has created a persistent slab avalanche problem. This weak layer is at all elevations near Cooke City. In all other areas, it is at mid and upper elevations and was unaffected by recent warm weather (see this layer in my video from Island Park yesterday, Dave's from Beehive, Alex's from Blackmore). My best advice is to not mess with this problem and wait until it gets buried deeply, and we stop seeing avalanches breaking on those facets.
Dangerous avalanche conditions exist throughout the forecast area and the danger is CONSIDERABLE
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