Sun and Aspect

Referred to as “The Range of Light,” the Sierra is known for having long sunny periods in between strong storm cycles. And although this makes for gorgeous weather, the sun is also the number one factor affecting snow quality. This is why aspect is so important. Northern aspects shade the snow from the scorching Sierra sun, and can often hold powder long after the snow has been melted off the trees and crust has formed everywhere else. From my experience, full sun can affect snow quality, even with air temperatures in the low 20s. This is why it is important to get an early start to sunny powder days, and ski the sunny aspects first before they turn to mashed potatoes.

Conversely, on warm, sunny days one can find beautiful corn snow on south, east and west aspects. Corn forms in light wind, on sunlit slopes when daytime high temperatures break into the 40s, and overnight lows drop below the freezing mark. With this sort of weather pattern, new snow can transform into silky corn in as little as 3 days. This freeze-thaw pattern is necessary in the formation of corn snow. We are lucky to get corn here in Tahoe, whereas other locations across the West often don’t see the temperature combinations necessary to produce it. In some locations, winters are too cold to thaw the snow during the day, and spring is too warm to refreeze the snow at night. In Tahoe, glorious corn conditions in pleasant, spring-like weather can occur during any month of the ski season, giving snow sliders a fun, warm weather alternative to powder skiing.

East aspects can hold both powder and corn. Given cold temperatures, forest shade, or cloud cover, eastern aspects can keep powder well. Also, given full morning sun exposure, eastern aspects can grow corn before the sun moves westward across the sky.

Skiing west aspects can be a bit tricky. Often west-facing slopes see the brunt of wind scouring from oncoming storms, as well as receiving abundant afternoon sunshine. Generally, skiing on western aspects will have less predictable coverage and snow conditions, but there are exceptions to every rule. In the longer days of spring, corn can grow nicely on western aspects, and without too much wind, powder can be found as well.