Rarely seen snow devil — or ‘snownado’ — recorded whirling across highway in Idaho

A rare weather phenomenon known as a “snowado” was seen spinning across a frigid mountain highway in Idaho.

It appeared Wednesday, Dec. 21, on U.S. 30 over Fish Creek Summit, and an Idaho Department of Transportation employee happened to be recording stock footage at the time. The summit is about 275 miles southeast of Boise.

“He was lucky enough to catch a snow devil on camera!” the department post on Twitter.

“Sometimes it is also called a ‘snownado.’ Whatever the name, it’s pretty cool!”

Snow devils are “a very rare phenomenon” caused when snow forms that resembles a white twister, according to the World Meteorological Organization.

“Surface wind shear acts to generate a vortex over snow cover, resulting in a whirling column of snow particles being raised from the ground,” the organization reports.

Though these albino snow devils are referred to as a “snownado,” the National Weather Service reports there have been real tornadoes of snow.

In 2013, a storm over over southern Ontario, Canada, developed into an EF1 tornado while temperatures were below freezing.

“Radar ... suggest that precipitation associated with the supercell was frozen ­— mainly ice crystals with a graupel storm core,” Weather.gov reports.

This story was originally published December 26, 2022 at 7:23 AM with the headline "Rarely seen snow devil — or ‘snownado’ — recorded whirling across highway in Idaho."