Bollettino valanghe

Mt Hood

Northwest Avalanche Center
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Pericolo valanghe

Sun
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
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In sintesi

We've entered a stretch of sustained mild temperatures that will last through the weekend.  On Saturday, wet loose avalanches are the main avalanche problem to contend with on steep sunny slopes with softer snow.  Don't let a small avalanche catch you off guard and take you for a ride in extreme terrain or near a terrain trap. 

Problemi valanghivi

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–1.5

    Mild temperatures and cloud cover Friday night will give way to sunshine and warmer temperatures on Saturday.  This is a recipe for wet loose avalanches.  If surface crusts do form overnight, they should break down quickly on Saturday.  You're most likely to trigger a wet loose avalanche on the southern half of the compass but pay attention to any aspect where you find the surface snow becoming wet as the day wears on. 

    The upper mountain and alpine terrain has been pretty wind-hammered over the last week.  You're most likely to encounter softer snow that's willing to move downhill in a wet loose avalanche near and below treeline. 

    The travel advice for wet loose avalanches is pretty straightforward - if the surface snow becomes wet and you start to see pinwheels, rollerballs, and/or small natural wet loose avalanches on steeper slopes, it's time to adjust your terrain choices.  You can shift aspects to more shady cooler slopes,  move away from terrain traps (cliffs, trees, gullies) where even a small avalanche could do damage, or simply shift to lower angle terrain.  

    (11/24/2022)

    Rollerballs like this are often indicators telling you the snow surface is becoming weak. 

    Photo: Robert Hahn

Avalanche Discussion

On Friday, forecaster Joe Dellaporta found widespread firm, wind-textured snow (chalky snow, sastrugi) above treeline on the south side of the mountain along with another helping of Vitamin D under sunny skies.  While a SE breeze was drifting small amounts of new snow at upper elevations, older wind slabs formed earlier this week were unlikely to trigger and no new avalanches were observed.  With the switch to E-SE winds over the last 2 days, cornices have been trimmed back and are not particularly large in many areas.  That said, we are entering a period of warmer weather, so make sure to give cornices a wide berth while traveling along ridgelines and limit your time below slopes with larger overhanging cornices.

On Thursday, Joe went to the Pea Gravel Ridge and used the ski area lifts to see several different aspects & elevations. On Pea Gravel ridge, he found another large natural avalanche on a SE aspect at 7300’. This avalanche likely occurred towards the earlier part of the week during one of our wind and snow events. Look at the picture in the gallery for more information. At lower elevations, he observed a widespread (mostly supportable) melt-freeze crust up to 5500’. 

Strong west winds from early last week built hard, stubborn slabs above treeline.  On Tuesday, Mt Hood Meadows Patrol triggered a large (D2.5) hard slab that broke 2-5 ft deep in one of their alpine bowls ( A-Zone 7200 ft, NE Aspect).  

If you get out let us know what you see by submitting an observation!

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