(CNN)When you're in the middle of yard work, you don't want to stop for just anything.

Maybe that explains why a man in Canada kept mowing his lawn even after a huge tornado reared up behind his house.

Cecilia Wessels took a remarkable photo of her husband, Theunis Wessels, pushing a mower Friday as a funnel cloud loomed over him in the background. She posted it to her Facebook page with a dryly witty caption, "my beast mowing the lawn with a breeze in his hair."

The photo raises an obvious question.

"Yes, he did know it was there," Cecilia Wessels told CNN. "He told me, 'I'm keeping an eye on it.'"

Wessels only took the photo so she could send it to her mom in South Africa. But the image has since found a much larger audience. It's been widely shared on social media and picked up by numerous media outlets.

Wessels said local storm chasers had told her the tornado was not as close as it appears in the photo. It was probably about a mile and a half away from their home in Three Hills, Alberta.

She said her family didn't panic when the tornado appeared because the breeze didn't pick up and no alarms were sounding.

"There was no sign we were in danger," she said.

Besides, the couple are natives of South Africa, where tornadoes are less common, so that may also have contributed to their lack of alarm.

Theunis Wessels was outside mowing for less than 10 minutes and was almost done with the yard when the funnel cloud appeared.

The weather that day started out looking beautiful, Cecilia Wessels said, and her husband "had it on the list to do the lawn."

So she took a nap, only to be awakened by their 9-year-old daughter, who told her "something was in the sky" and daddy wasn't coming inside.

But hey, he had a job to finish.

Her husband saw the funnel cloud form, she said, but wasn't too worried about it because he had been to a storm chasers' forum a few weeks earlier and knew what to do if it got too close.

Wessels said she's been stunned by the reaction to the photo. She's been getting about a hundred messages and 60 friend requests a day since the image went viral. She's also been seeing a ton of "Wizard of Oz" jokes and memes.

Her husband's reaction? He's very nonchalant about the whole thing and isn't interested in any of the hoopla, she said.

Three Hills is a rural area northeast of Calgary, so the twister did a little bit of structural damage to a few buildings, but that was about it. No one was hurt as it zipped through.

But the Wessels know what to do next time. During an interview, a local radio station host told Cecilia Wessels that if they ever see a funnel cloud on the horizon, they better "get inside faster."