Grand Canyon inversion

A rare total inversion was seen over the weekend by visitors to Grand Canyon National Park. This view is from Mather Point on the South Rim. Cloud inversions are formed through the interaction of warm and cold air masses. (Erin Whittaker / National Park Service / November 29, 2013)

  • Also
  • Storm brings winter to Southwest Storm brings winter to Southwest
  • 'Off the charts' November storms led to record-breaking tornadoes 'Off the charts' November storms led to record-breaking tornadoes

All clear Tuesday! But for a few days a rare atmospheric phenomenon created a layer of clouds in the massive mile-deep walls of the Grand Canyon, creating an awe-inspiring sight. 

Weather conditions allowed an inversion layer to trap what looked like a white ocean of fog in the canyon when viewed from higher ground. National Park staffers said that when it first arrived Friday the scene was among the most dramatic in the park in decades. 

"It was a typical commute to work, and all of a sudden we were like, 'Oh my God,' " Erin Huggins, lead park ranger for the Grand Canyon National Park, told the Los Angeles Times. "We all started freaking out and calling everybody and running to the rim and taking pictures."

Huggins said she has seen inversion layers occasionally trap some clouds in the canyon, but they usually burned away quickly.

"But this one lasted almost three or four days,” Huggins said. “My boss has been here for 20 years, and she says she hasn’t seen anything like it. Kind of amazing."

Robert Bohlin, a meteorologist for the National Weather Service in Flagstaff, Ariz., told the Los Angeles Times that it was the first major inversion to roll over the canyon since December 2004.

“It’s pretty rare," Bohlin said, attributing the phenomenon to the intense rains that passed through the region shortly before Thanksgiving. 

According to Bohlin, the inversion refers to an atmospheric flip-flop that happens when cold air gets trapped beneath a layer of warm air, pinning the cold air against the earth. The higher up you get, the colder temperatures tend to be, but an inversion flips that around.

In the Grand Canyon, the sun warmed the ground, which began to evaporate the moisture. But the moisture was was pinned close to the earth by a blanket of warm air, Bohlin said. Enough water evaporated and condensed, and, poof -- clouds formed.

Bohlin said that the weekend's weather was the 12th such inversion layer to collect over the area since 1952.

It appears to be too late to catch the phenomenon with your own cameras. On Tuesday Huggins said the clouds had "cleared out." But you can take a look at some of the park's photos below.