What is a fire tornado? 'Extreme fire activity' sparks rare weather warning at Loyalton Fire near Reno.

This year is full of things most people have never heard of and probably never want to see for themselves.

"Fire tornado" is the latest entrant on 2020's list of new, scary and destructive things. The "extreme fire activity," brought on by conditions in the ongoing Loyalton Fire in Northern California, was recorded Saturday by the National Weather Service in Reno, Nevada.

Conditions surrounding the rare fire tornado, also known as a "firenado," prompted NWS Reno to issue a tornado warning related to the fire, the first warning of its kind, Dawn Johnson, senior meteorologist with the weather service, told USA TODAY.

"Essentially, it's just very dangerous conditions for any firefighters and, really, anybody in the vicinity of the wildfire," she said.

Remember murder hornets? Hundreds of people think they've spotted the Asian giant hornet

Johnson said preliminary reports indicate the tornado spawned by the fire was the equivalent of an EF-1, which packs three-second wind gusts between 86 mph and 110 mph, or an EF-2, with three-second gusts between 111 mph and 135 mph. She said the event took place east of Loyalton, California, and west of Cold Springs, Nevada.

For comparison, there was a firenado due to the devastating Carr Fire in Northern California in 2018, later determined to be the equivalent to an EF-3, with three-second gusts between 136 mph and 165 mph.

This photo provided by Katelynn & Jordan Hewlett, a funnel appears in a thick plume of smoke from the Loyalton Fire is seen in Lassen County, Calif., Saturday, Aug. 15, 2020. A wildfire in Northern California on Saturday spawned at least one fire tornado that prompted the National Weather Service to issue a tornado warning. The Loyalton Fire in Lassen County, Calif., burned intensely amid hot and dry conditions on Saturday afternoon. (Katelynn & Jordan Hewlett via AP) ORG XMIT: LA701

"There have not been very many of these that have been documented," Johnson said, adding that she's only been able to find documentation for four firenadoes in the last 15 to 20 years.

Smaller scale fire whirls, she said, are much more common.

Devastating weather: Iowans grapple with aftermath of deadly derecho, 'a disaster that we have never seen'

The fire tornado was generated because of the intense heating of the wildfire, Johnson said. The Loyalton Fire had burned 20,000 acres as of Sunday afternoon with no containment, according to the Tahoe National Forest.

"This is a very similar process to what we'd see in the thunderstorm where you'd get these rising updrafts in a thunderstorm and the thunderstorm clouds grow to 30,000, 40,000 feet," Johnson said. "But, in this case, it was a fire and it was smoke."

All of the air rushing upwards has to be replaced at the surface, Johnson said. As air comes back it, sometimes, starts to rotate. Due to wind shear on Saturday, the air that was rising from the fire and the air that was replacing it started to rotate.

Lake Fire: Southern California wildfire feeds on 'decadent' fuels, grows to nearly 18,000 acres in Angeles National Forest

"Between that and the local effects of terrain — we have mountains and valleys all over the place surrounding where this fire is — we would get this little spin-ups," she said. "We'd get these stretching columns of air that are now rotating and, as they elongated, it actually produced these vortices and the tornado we saw from the fire."

It'll take some time to send in a team to do a proper damage assessment of the fire tornado because, as Johnson put it, "It's on fire."

"We just want to make sure anybody who is in the vicinity of the fire is heeding evacuation orders and staying away if they don't need to be in there," Johnson said. "We want to make sure everyone is staying safe — that includes firefighters there on the ground."

This article originally appeared on USA TODAY: 'Fire tornado' spawns at Loyalton Fire in California, prompts warning