Mt Hood

Make sure you can have the tools and skills to arrest a fall if you encounter very firm crusts. If the sun does warm snow surfaces, large cornices may weaken and fail or you can also trigger a small wet loose avalanche on a steep southerly slope.

Moderate winds continued on Saturday with Mt. Hood Meadows Patrol reporting limited softening of pervasive crusts despite the mercury climbing above 50F. We expect similar conditions with slightly more high clouds and slightly lighter winds on Sunday.

Near-record temperatures for multiple days in a row would typically have us very concerned. However, there are several factors that have prevented an avalanche cycle this time around: 1) Long winter nights and generally clear skies this time of year have contributed to the snowpack refreezing. 2) The low sun angle limits the duration of sunshine on any given surface. 3) Two wet avalanche cycles and 12 days of predominantly above freezing temperatures have transitioned the snowpack to be able to handle more unseasonable warmth.

We're heading into Sunday with more 11,000 to 12,000 ft freezing levels. Adopt a spring travel mindset if you head into the mountains.

1. Slide for life conditions exist during the morning hours at all elevations. Above 7000 ft, crusts are unlikely to soften due to the presence of bulletproof blue water ice. These conditions were confirmed by an observation on Saturday. Consider your ability to self-arrest and the tools you have to do so before traveling on an icy slope.
2. Large cornices remain a hazard as warm temperatures continue to weaken them. Give them a wide birth on the ridges as you travel and don't linger on the slopes beneath them.
3. As soon as the winds die down, crusts will begin soften on aspects directly facing the sun. Once this transition occurs, you can trigger small wet loose avalanches on steep SW-S-SE slopes once the crusts break down. These avalanches are primarily a concern near terrain traps where they could push you into rocks, trees, creek beds, or over a cliff.
4. Rime ice continues to eject off rocks in the alpine and the upper slopes of Mt. Hood. These chunks of rime ice can accelerate while sliding down the firm surface crusts and could easily injure and possibly kill a person.
5. Glide cracks have opened up and pulled away from rocky outcrops. Note the locations of existing large open cracks and limit your time below similar terrain features. Glide avalanches take the entire snowpack with them and with over 80" of snow on the ground, they could be quite large.

Mt. Hood picked up 2" of water equivalent January 19-20; most of that water fell as rain or freezing rain into above treeline terrain. Up to several inches of dry snow fell at the tail end of the storm. Strong W, then NNW winds through early Friday blew or sublimated much of that snow off the mountain. NWAC forecaster Andrew Kiefer reported challenging travel conditions due to the extensive crusts in the Timberline area. He found sastrugi on top of water and rime ice, but no wind slabs. He also observed a recent natural cornice fall. You can read his full report here.