The National Weather Service and CalFire’s Serious Accident Review Team conducted a preliminary damage survey on the Carr Fire in which they found that the “Firenado” produced 143 MPH winds, equivalent to an EF-3 tornado.
The whirl was produced between 7:30 p.m. and 8 p.m. on Thursday, July 26 as the wildfire burning from Whiskeytown moved into the City of Redding.
“This is historic in the U.S.,” Craig Clements, director of San Jose State University’s Fire Weather Research Laboratory, told BuzzFeed News. “This might be the strongest fire-induced tornado-like circulation ever recorded.”
The NWS & @CAL_FIRE Serious Accident Review Team (SART) are conducting a storm damage survey regarding the large fire whirl that occurred Thursday evening in Redding. Preliminary indicators placed max wind speeds achieved by the fire whirl in excess of 143 mph. #cawx #CarrFire pic.twitter.com/3iRX90lhLJ
— NWS Sacramento (@NWSSacramento) August 2, 2018
The EF scale refers to the Enhanced Fujita scale, which measures tornados from 0-5, with 5 being the worst. An EF3 Tornado is described as causing severe damage, including well-constructed houses destroyed, trees debarked and heavy cars lifted off the ground.
Photos shared by NWS Thursday show collapsed power line towers, the charred remains of a car, uprooted trees and remnants of brush. The damage report also noted the complete removal of tree bark.
The winds uprooted trees and blew off roofs, causing devastating damage on top of the many structures burned to the ground:
— Mike Chapman (@mikechapman_RS) July 27, 2018
Scientists are saying that in order to create this “Firenado” phenomenon, flames have to become so intense that it created its own weather system. When the fire sucks the oxygen out of dry plants, the force of that suction creates strong gusts of winds. When the fire gets so intense, the winds pick up around the flames, creating a self-sustaining tornado of flames and destruction.
The biggest shock to researchers was just how fast the tornado formed. On Thursday evening, the smoke cloud quickly doubled in height, surging upward nearly four miles in 40 minutes. When a vortex near the ground is stretched, it intensifies — likely the main ingredient in tornado formation.
Below, you can see illustrations of the tornado:
While the National Weather Service forecast office in Sacramento described the vortex as a fire whirl, many analysts are suggesting this was an actual tornado. Fire whirls are much more common.
“I’m relatively comfortable calling this a tornado; I’m sure some people will take issue with it,” Neil Lareau, a physics professor at the University of Nevada at Reno, told Axios.
However you want to classify the weather phenomenon caused by the Carr Fire, the damage will be felt for many years to come. The Carr Fire currently sits at 141,825 acres and 41 percent containment. The fire has claimed six lives and destroyed more than 1,500 structures, making it sixth most destructive fire in California history.