If the conditions are just right on a hot summer day, you might just come across a whirlwind like the pool-goers at the Kroger Aquatic Center in Huber Heights did Saturday.
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A whirlwind, also known as a dust devil, is a relatively small, rotating column of air initially formed from calm winds, plenty of sun, and generally dry conditions, according to News Center 7 Meteorologist Jesse Maag.
Crystal Hagans told us an umbrella flew over her head during the whirlwind at the Kroger Aquatic Center located at 8625 Brandt Pike . Hagans said clothes, shoes and lounge chairs were picked up by the whirlwind as well.
Lifeguards were able to get everyone out of the pool and take shelter, Hagans said. They checked to make sure no one had been hurt.
“For me, it was exciting but I was surprised when it happened,” said Hagans.
The birth of a whirlwind starts with sunshine heating the ground which then heats the air immediately above it. This process is known as conduction. Once the air just above the ground is heated, it rapidly rises into the relatively cooler air above.
As it rises it creates what is called an updraft. The updraft quickly transports air from the surface several meters into the air, Maag said.
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After the updraft takes places, air from all around the base of whirlwind rushes in to fill the void left by the air previously located there. Since the air rushing towards the center of the whirlwind is also hot, it meets at the center and continues to feed the updraft.
This cycle continues until heat is lost at the surface or the overall calm surface conditions are compromised. Whirlwinds are generally harmless to adults, but on rare occasions they have been known to knock people off of their feet. It’s best for small children to steer clear of these.