Bollettino valanghe

Snoqualmie Pass

Northwest Avalanche Center
Vedi sulla mappa

Pericolo valanghe

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

In sintesi

East winds will continue funneling through Snoqualmie Pass and moving snow onto leeward slopes on Friday. Look for textured surfaces or pillow-like drifts to help identify wind-loaded features where you’re more likely to trigger an avalanche. They could be in unusual locations or break in surprising ways.

Problemi valanghivi

  • Wind Slabs

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

    Easterly winds should be reinvigorated Thursday night and Friday. This could thicken existing slabs or build new ones on leeward slopes, convex features, or near rocky terrain. Due to the easterly wind direction, these slabs may develop on different aspects than you’re used to. They could also form further down in the terrain as slopes get cross-loaded. You can use small test slopes or uptrack tests as you travel to determine how sensitive these slabs are. Look for actively blowing snow, new cornices, textured surfaces, or fresh drifts to help identify wind-loaded features to avoid.

    (2/14/2024)

    Signs of wind loading, particularly during an east wind event. Use these visual clues to help identify wind-loaded aspects.

    Photo: Andy Harrington

Avalanche Discussion

The storm dropped roughly 3-6 inches of low-density snow at the Pass. Winds gusted into the 50 mph range on Wednesday night before tapering during the day on Thursday. Expect those wind speeds to ramp back up during the day on Friday and start moving snow again. 

Observations from Thursday are a bit limited, but Alpental Pro Patrol observed isolated shallow slabs during their morning mitigation work. Avalanche professionals in the Alpental Valley reported propagating results during stability tests on the Early February Crust (EFC) at lower elevations. NWAC forecasters found weak snow grains at this interface earlier this week. 

Snow depths over the Early February Crust (EFC) are deeper on the shaded half of the dial than on slopes that typically see direct sunshine. On sun-exposed aspects, the snow over the EFC contains a series of crusts interspersed with weak grains. You should focus your observations on the snow above the EFC on Friday.

You could have to manage some loose snow avalanches on Friday. Don’t get tripped up by a small sluff on wind-sheltered steep slopes. Solar-induced loose avalanches could run on an underlying crust if the sun comes out. They could be dry, moist, or even wet. The sun will have to outduel the cold wind to really set things off.

Regioni coperte