Hooray for SWE

From the THR Dept. of Atmospheric Rivers… A wee bit into March and the reality that my pal in Truckee gets to rev his snowblower as the latest atmospheric river moisturizes the Sierra Nevada means it’s time for a SWE update. As we’ve been doing here at THR throughout the winter, we’re looking at some maps to get a general idea of Snow Water Equivalent (SWE) on the ground. As many of you know, SWE gives us a picture of the water content in the snowpack. As trends go, we expect SWE totals (a % of average) to increase throughout the winter and early spring. 

As a community, we like to see color tones from green to blue on the SWE maps. As the map legend explains—green means basins are bumping into the near or over 100% SWE. If your zone is green to a deeper shade of blue as we move into March, we assume you’ve been driving the reverse camber wide-under-foot powder boards. On the contrary, if you reside where reds, oranges, and yellows are the color of the month, you’ve either been farming leeward slopes for fresh snow or blissfully scratching edges against a pallet of firm snow conditions. Either way, it’s snow sliding, which is better than the alternative.

The good news is that we’ve seen colors more agreeable to snow sliders, agronomists, and hydrologists since last month. California looks like its SWE bank account is growing, which may spawn ski traverse dreams for potential Sierra point-to-points this spring; the PNW continues to be somewhat of a mix. Oregon looks moist, whereas the northern portions of the region continue to lag in SWE accumulation. 

Zooming in on the West.

Observing the upper belt of the Continental U.S., the yellows and oranges persist through Idaho and, generally, the Northern Rockies. The Central and Southern Rockies are a patchwork of greens and yellows that align with positive SWE trends as winter advances. 

Sticking with the theme of analyzing SWE via the ROYGBIV lens, the Coast Range and the vast mega-scape of Alaska are setting up for a lengthy spring touring season. Curious Alaska folks, do some up there fear higher SWE totals as it may correlate to higher mosquito totals? Either way, some here at THR are envious of the terrain up there. 

Zooming in on Alaska.