Winter Storms Bring ‘Upside-Down’ Snowpacks to National Parks

A sweep of winter storms have caused “upside-down” snowpacks across several U.S. national parks.

The West and Southwest have seen some severe winter storms in recent days as two atmospheric rivers brought an onslaught of snow and rain to the regions.

California saw extremely heavy rain from January 31 to the start of February, as the first atmospheric river made its way across the state. The second came into the atmosphere between February 4 and 6. Both these rivers caused flooding in low-lying areas and a dumping of snow in the surrounding mountains.

The recent stormy conditions were at odds with the temperatures throughout January, which towards the end of the month were unusually warm. This has seen some “upside-down” snowpack accumulating in the mountains, according to Yosemite National Park.

The California park posted some pictures of the landscape glistening with the new mounds of snow.

“Our Tuolumne Meadows winter rangers have been experiencing mixed messages in the high country this winter. The end of January saw record warm temperatures, and the start of February brought two atmospheric rivers that brought welcome new snow to the Sierra Nevada and over 100+ mph winds at several locations,” the park said in a Facebook post.

“The most recent storm resulted in an ‘upside-down’ snowpack in that the storm started cold and got warmer as it progressed. This means that colder and drier snow now has warmer and wetter snow on top of it. Not an ideal recipe for stellar ski conditions, but the much-improved coverage and deeper snowpack is a worthwhile trade off.”

In a later post, the national park warned that this snow would melt quickly with warmer temperatures expected to set in this week.

When a large amount of snowpack accumulates in the mountains, and melts all at once with warm temperatures, there is a risk of flooding. Last spring, Yosemite saw extremely high flows in the Merced River after a record amount of snowpack melted. This also caused flooding throughout the park.

Yosemite is not the only park seeing effects from these storms.

New Mexico’s Valles Caldera National Preserve received upwards of 5 inches of snow in just two days, a Facebook post on February 9 said.

“At this time, the estimated snowpack in Valle Grande ranges from 21 to 28 inches, except in areas of drifting snow,” the preserve said.

The park also posted a picture of trail managers shoveling the high levels of snow to a background of blue skies, following the storms.

Utah’s Bryce Canyon National Park also experience heavy snow as the storms made their way to the Southwest.

The park posted photos of the glistening snow around the canyon.

“And there it is! As winter Storm Kayden rolls on, it leaves behind 27 inches of snow on trails, rocks, and trees,” the park said in a Facebook post.

The west and southwestern regions of the U.S. is typically very dry. This has been the case in recent years as an ongoing drought plagued the area. However, throughout 2023, and at the beginning of this year, the region seems to be receiving a welcome amount of snowpack.

When drought conditions were happening, reservoirs and rivers in the area were experiencing very low water levels. This accumulation of snowpack, however, should help replenish them.

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