Bollettino valanghe

Tetons

Bridger-Teton Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Sat
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
2 · Moderato
Open full map
Non aggiornato — questo bollettino è scaduto 2 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Rapidly changing conditions will increase avalanche danger during the day. Heavy rates of snowfall combined with strong SW wind will form reactive wind drifted slabs. Careful terrain choice will be necessary as human triggered avalanches in steep, wind loaded terrain will be likely in the middle and upper elevations. Reassess new snow instability throughout the day. 

A Winter Storm Warning is in effect from now until 11:00pm Saturday.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–2

    Loading of new snow last night and today with strong (near gale) winds will form reactive slabs 1-3 feet deep in the middle and upper elevations. These slabs will grow deeper and more reactive during the day with rates of snowfall 1-2 inches/hour and 8-12 inches of snow forecasted today. Ridgetop winds at 10,000’ are averaging 30-40 mph with gusts to almost 70 mph out of the southwest. Expect slabs to form further below ridgelines and on cross loaded terrain features, such as gullies, due to these intense winds. Look for signs of wind affected snow such as hardness changes, stiffened surfaces, cracking, and large pillows/drifts. Seek sheltered terrain and monitor changing conditions throughout your travels. 

    Storm slabs 1-2 feet deep deep could break across all elevations in steep terrain that is not obviously wind affected, especially near large wind funnels such as canyons. Lower elevation slabs will be less than a foot deep. 

    (2/24/2024)

    A wind slab that caught and carried a skier 500 feet in Grand Teton National Park.

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely
    Dimensione
    2–3

    Weak layers are persisting in the snowpack beneath hard slabs 3-5 feet deep. These weak layers have been trending dormant. Avalanches involving new snow could step down to these deeper layers where the snowpack is thin. Thin spots (trigger points) where the overlying slab is shallow and riders can impact these weak layers are most common in steep, rocky, unsupported and wind affected terrain. Slopes that previously avalanched on deeper weak layers in Jan/Feb should be on your radar for repeat offenses.Managing terrain choice for the wind slab problem will help you manage this problem. 

    The last avalanche involving persistent weak layers was triggered by a large cornice fall on 2/21. The last human triggered avalanche on these layers occurred on 2/10.

     

    (2/17/2024) Photo: Teton County SAR

    A very large persistent slab avalanche that occurred on No Name Peak after a period of significant loading.

Avalanche Discussion

March Madness

We are starting March off with an impressive storm cycle as this atypical winter improved dramatically over the last month. Areas favored last night have already received 6-8” of snow in the Tetons. This is great news, except the radically strong winds associated with this storm are unfavorable creating dangerous avalanche conditions. Another foot of snow is expected today with continued strong winds decreasing slightly 20-30 mph still out of the southwest in the afternoon. This will require you to constantly reassess that new snow instability throughout the day. Keep your eye out for fresh wind slabs forming by looking for those obvious signs of instability. Those subtle changes in snow texture will be critical to clue in on. Open and exposed terrain will be where you will most likely encounter unstable snow. Seeking lower angle terrain will help you reduce uncertainty in any new snow instability. Check back throughout the weekend as avalanche danger will continue to rise with more snow and wind forecasted. 

Regioni coperte