Mt Hood

Firm crusts and glare ice elevate the risk for uncontrolled falls. Ensure you have the skills and tools to self-arrest. Avoid lingering below softening cornices and watch for wet, slushy snow on steep sun-exposed slopes as the day heats up.  

Despite the high freezing levels this week, only steep southerly slopes have been softening. With freezing levels rising up to 11,000 ft on Friday with light winds, we expect more of the same on Friday. If you plan to ski, ride, or climb Mt Hood this week, keep the following in mind:

1. Falls may result in uncontrollable slides on aspects not receiving direct sunshine. Consider your ability to self-arrest and the tools you have to do so before traveling on an icy slope. Crampons, whippets, or an ice ax may be adviseable.
2. Many ridgelines are melted out to the bare ground, and rockfall has been frequent in several canyons recently. Stay alert when traveling, and identify areas where you may be exposed to rockfall from above.
3. Some cornices remain a hazard with continued sun and warm temperatures. Give any remaining cornices a wide birth on ridges and don't linger on the slopes beneath them.
4. Many creeks have reopened and snow bridges continue to collapse. Take time to make a careful assessment if crossing any creeks.
5. The wet loose cycle has largely run its course. Any additional wet loose activity would be small human triggered slides in extreme, rocky terrain late in the afternoon. Monitor snow surfaces on sunny slopes as they thaw throughout the day, and move to shadier aspects or low-angle terrain if the snow is deep and slushy.

You're probably wondering why the snowpack is so firm and icy given freezing levels rising to near the top of Mt. Hood? (1) Long winter nights and generally clear skies continue to allow the snowpack to freeze hard by morning. (2) The low sun angle limits the duration and intensity of sunshine on snow surfaces, and a thick surface crust is slow to melt. (3) Low humidity allows any melt to evaporate and cool the snow surface.

 Two wet avalanche cycles and two weeks of predominantly above freezing temperatures have transitioned the snowpack to be able to handle more unseasonable warmth. During this time, the overall height of snow decreased by nearly 3ft at the Mt Hood Meadows Base weather station (5380ft) since January 6th. Many ridgelines are snow-free and steep rocky slopes continue to melt out. Travel conditions have been challenging recently, with firm and icy surfaces everywhere. If you time your travel well, SW-S-SE aspects will likely transition to smooth corn by late morning or afternoon. Check out this observation for more information on conditions from Tuesday in White River Canyon.

The next storm cycle should commence on Sunday. Please help us monitor snow surface conditions by submitting an observation.