Barrie city councillor Natalie Harris said it happened quickly.

Harris was visiting her son and dogs at her ex-husband's home Thursday afternoon when she said he called and advised them to go to the basement.

Holding on to her son, Harris told CP24, she saw that "something was clearly happening" outside and dust started to come down in the basement.

"If you could imagine Mother Nature ripping half your house off -- that's loud," Harris said. "It was just so loud, and the power went out."

"I thought maybe this is it. Honestly, we didn't know when it would end. And there was no question it was hitting our house."

When they emerged from the basement, Harris said she could not believe what she saw.

"When I looked up the stairs and saw the sky, and we knew we didn't even have a roof," Harris said.

Tornado damage

The home is one of the many houses in the neighbourhood that suffered damage when a tornado touched down near Prince William Way and Mapleview Drive Thursday afternoon.

Officials described the damage from the storm as "catastrophic" and not unlike what you might encounter in a "war zone."

Eight people were taken to hospital, including four with serious injuries. Barrie Mayor Jeff Lehman said there are no confirmed fatalities at this time.

"I can't tell you how incredible it is that nobody has been killed. And I hope that as all the secondary searches are completed, and the patients are treated at the hospital, that that continues to be the case because this certainly could have been a much more serious disaster," Lehman said.

READ MORE: Widespread damage reported after possible tornado touches down between Barrie and Innisfil

As for Harris, she said it's going to take a while to process what happened.

"We just all couldn't believe it. We were just like, oh my god, I can't believe this happened," she said.

Harris said she is grateful for the quick actions of her ex-husband, who is a paramedic.

"My son's room is the front of the top of the house where all the glass busted in, and the roof is gone. He's usually up there doing whatever on his computer… Thank God that [he] called and said, get in the basement right now and we did," she said.

"We live in Barrie. We get tornado warnings on a regular basis. And sometimes you go, and sometimes you don't, to be honest. And if we didn't, I don't know what would have happened."

Sophie Vienneau was driving her truck when she saw the tornado coming towards her. She captured the moment on video and posted it on social media.

"When everything went down, it was really scary," she told CP24 Thursday evening.

"I got a warning on my phone just as I turned onto Mapleview from the 20th Side Road and by the time I got up to the hill, I just seen it come down in front of me. And it just it literally happens so fast."

Tornado

At that moment, all she could do was pray for her gravel truck to stay on the ground. Vienneau said the incident lasted approximately 60 seconds, with flying debris hitting and damaging her truck.

"If it wasn't fully loaded, then I think it would have tipped me over for sure," she said. "I felt it. I felt like the truck was going to tip over, but thankfully it never did."

Vienneau said she has never before experienced being caught in a tornado.

"I pray and hope for everyone," she said.

IN PHOTOS: Tornado Hits Barrie

David Belitshi was not home when the tornado hit. He became concerned for his wife and children as he drove past by and saw the devastation that occurred.

"I just wanted to get my wife and the kids and get them out," he told CP24. Luckily, Belitshi said his wife was able to pull the children to the basement before the tornado arrived.

"They were pretty rattled," he said.

His house sustained extensive damage – windows shattered, roof destroyed, fences taken off. He has been told by crews that his house is deemed unsafe.

"I've never seen anything like this. Pretty, pretty devastating, but along as my wife and kids are fine," Belitshi said.

"The fact that people were okay, and people were able to get out of their house or take cover, I think that's the main thing that you're just happy and grateful for."