Bollettino valanghe

Presidential Range

Mount Washington Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Sun
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
2 · Moderato
Open full map
Non aggiornato — questo bollettino è scaduto 4 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Dangerous avalanche conditions exist on steep east-facing slopes at middle and upper elevations. Areas of thick wind-drifted snow can avalanche naturally or by the weight of a person. Cautious route-finding and informed, conservative decision-making is critical when traveling in or near avalanche terrain today. 

Problemi valanghivi

  • Wind Slabs

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

    Thick wind slabs sensitive to the weight of a person will continue to form throughout today and tonight at middle and upper elevations on steep east-facing and south facing slopes.  Steadily increasing wind speeds overnight have formed strong-over-weak slabs that could be 1-2 feet thick. Cross loading winds will allow  wind slab formation on adjacent slopes.

    If the snow you are traveling through becomes deeper and denser you've found a wind slab. Cracks shooting out from in front of your skis are clear indications that the slab you found is unstable. Look for blowing snow at the ridgelines as a red flag to know that northwest wind is loading snow onto east facing aspects. Signs of overnight avalanches are a sign that slopes are unstable. 

    Watch for wind slabs forming higher in the terrain due to low-moderate wind speeds. Soft loose snow at the bottom of a gully may not be representative of a stiff wind slab at the top of the gully. When climbing a slope, pay attention to changes in snow stiffness as you ascend using frequent hand shear tests. 

    Also keep in mind the dynamic nature of developing wind slabs throughout today with the possibility that slab size and sensitivity will likely increase from continual loading from a consistent wind speed.

  • Loose Dry

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1

    The 10 inches of snow blanketing the terrain at all elevations may slide if released by a skier or climber.  Small Loose Dry snow avalanches were observed yesterday in Tuckerman Ravine. Low wind speeds overnight may have preserved some areas of loose new snow in wind sheltered locations. 

    Loose snow avalanches will be small, but consequential in steep terrain if you get pulled off your feet.  

Avalanche Discussion

With a storm total of 10 inches under light wind speeds, followed by wind shifting northwest in the afternoon and increasing we expect to find new wind slabs in east-facing ravines. The question for observers today is: where, how thick, and how sensitive. 

The forecaster team this morning had a pretty good handle on where. We expect to find new slabs in east and southeast aspects. More precisely, we are expecting these slabs to be found higher up in the gullies due to the low to moderate wind speeds. Light wind speeds also tend to result in an upper snowpack structure that’s more reactive to trigger than we typically see from higher wind speeds transporting snow. 

Some uncertainty exists on the size of new wind slabs, also due to the wind speeds. Slow to build wind slabs are more likely to be found in the terrain this morning, with steady continuous loading increasing the size over the next 24 hours. 

The Lion Head Summer Trail is OPEN. Watch for drifting snow piling up. If deep snow is found, retreating and using the Winter Lion Trail is the safer option. 

OBSERVATIONS: Please consider submitting an observation of what you are seeing in your travels. Submitting an observation hones your skills, informs other users, and improves our forecasts. 

Regioni coperte