TOPEKA (KSNT) – A blazing fire at a warehouse south of Topeka in early March generated a twisting vortex of flames.
During the fire, KSNT 27 News received videos from a man at the scene that showed what appeared to be a ‘fire-whirl’ extending from the base of the fire up into the smoke plumes above. The footage managed to capture the tornado look-a-like; but scientists say that they are more often referred to as ‘fire-whirls.’
KSNT 27 News reached out to Chip Redmond, a meteorologist with the Kansas Forest Service and Kansas Mesonet for a scientific explanation.
“The fire’s heat and resulting upward motion, combined with light ambient wind, creates enough shear/vorticity to stretch in flowing oxygen into the column and create a short lived fire-whirl,” Redmond said.
Redmond went on to comment on a few different aspects of the oddity:
“They’re usually called ‘fire-whirls’ unless they become destructive,” Redmond said. “They’re fairly common in a fire environment with light enough winds to allow convective heat to rise but enough wind to enhance vertical shear. The temperature needed for them to occur varies with fuel and the atmospheric environment. You can see them off of the smallest fires depending on the power of fire versus the power of the wind.”
A lot of the terms that Redmond mentioned are actually shared with the world of weather: shear, vorticity, convection, etc. Weather plays a big role in fire behavior and can have significant implications on how quickly (or slowly) a fire may spread.
“[Fire-whirls] have no implication on the danger, or strength, of a fire unless they become violent – more atmospheric driven driven in that case, think tornado,” Redmond adds. “They are definitely a sign of a lot of heat though!”