Cascade Snowpack Makes a Comeback

I went skiing at Mt. Hood Meadows last week, and even though the powder that day was fantastic, the coverage was anything but, with rocks, bushes and sticks protruding from the snowpack at every turn. It’s been a mediocre winter for the Washington Cascades, but the Oregon Cascades are in far worse shape, and conditions are downright depressing in the Sierra Nevada and Intermountain West. Mammoth Mountain, for example, has (as of 1/23/2018) only received 69” of snowfall this season. Thank goodness for snow-making machines!

The reason for such a lack of snowfall is because we’ve had the deadly combination of above normal temperatures and below normal precipitation for much of the West this season. This is due to a series of large ridges over the area during December and the first half of January. This is atypical for a La Niña winter such as the one we are in, as we usually see ridging far offshore and troughing over our area during these years, giving us cooler/wetter than normal conditions and above-average snowfall.

Thankfully for skiers, snowboarders, water supply managers, and nearly everybody else west of the Continental Divide, we entered a much more active pattern more reminiscent of what we’d expect during a La Niña during the latter half of January. A persistent trough over the Northeastern Pacific helped direct wetter and cooler-than-normal weather into the Pacific Northwest, resulting in impressive snowfall totals across both the Washington and Oregon Cascades, with lighter snowfall in the Sierra Nevada and Intermountain West.

La Niña’s effects are most prevalent from January through March and even into April in some years, so there’s still some hope for a substantial recovery in snowpack across the Cascades for the rest of the season. Unfortunately, because La Niñas are also typically associated with a more northern storm track, the Sierra Nevada and Intermountain West could miss out on most of the snow when they are the ones who need it the most. California and the Intermountain West tend to have more year-to-year variability in their snowpack than the Cascades (especially the higher terrain in the Northern Cascades), so while these meager totals are nothing new, they are nonetheless discouraging, particularly after the epic 2016–2017 season that brought record rains to much of the West Coast and record snowfall in the Sierra Nevada, finally erasing California’s drought.

So while we’ve gotten a slow start to the season, things are certainly beginning to pick up, and with any luck, February will be snowy month for the Cascades and Olympics. Viva La Niña!

~Charlie Phillips

Charlie Phillips, a Madrona resident, received his B.S. in atmospheric sciences from the University of Washington and works in Portland as a meteorologist forecasting wind energy along the Columbia River Gorge. Check out his weather website at weathertogether.net.