The tornado has been rated as an EF-1 with peak wind speeds of 95 mph, the National Weather Service said.
It started at 7:11 p.m. and was on the ground for two minutes. It had a path 1.13 miles long and had a maximum width of 150 yards.
Viewers captured video of the funnel cloud as it passed by a shopping center. It blew off parts of the roof of an Acme store on Kirkwood Highway.
NWS: Confirmed tornado touched down near Marshallton, Delaware
"It was like the movie Twister. It was just flattened. Everything was picked up, twirled and thrown," said Glenda Sterling, who lives on West Robino Drive in Mill Creek.
The powerful storm destroyed her backyard and parts of her house, including the roof.
"We're cleaning up. It will be fine. It will all get worked out. I'll get a new roof, I'll get a new fence, and new windows," she added.
Tornado damage cleanup underway
Chainsaws could be heard along the tornado's path on Friday morning as the cleanup began.
Drone 6 showed the line of damage after powerful winds tore up sections of the Sherwood Park 1 neighborhood near the Delcastle Recreational Park.
"I didn't stop shaking for like three hours afterwards. It was very scary," said resident Jami Agden.
"I thought we lost the roof. It was very, very loud," Agden continued. "It sounded like a train."
Other neighbors say they heard the same thing.
Some people got alerts on their phones telling them to take cover immediately.
Kelly Ashton said it all happened very fast.
"I mean, it's full-blown anxiety. You go into a full-blown panic. I'm a mom, so it's insane and you're like, 'Oh my gosh, what do we do?'"
How residents are recovering after EF-1 tornado hits Delaware
Some people reported that skylights were sucked right out of their homes.
"I've heard of that," said Ted Rock, owner of Rock Roof. "Crazy stuff happens."
Delmarva Power says about 2,500 customers in New Castle County lost service.
The company along with local leaders say they'll continue to monitor the remnants of Debby while restoring power and neighborhoods.
New Castle County Executive Matt Meyer urges residents to call the emergency management office if you have any questions or see damage or unsafe conditions.
Some areas flooded during the storm
Over in Bear, Delaware, first responders were sent to rescue residents trapped in floodwaters. Mandatory evacuations were put in place for some people living in nearby mobile homes.
Janet Blottin watched as the waters rose to heights she'd never seen before.
"I'm worried I'm not going to be able to get back to my house. I have a husband at home that's disabled and four dogs. I'm just hoping everything there is going to be OK," she said.
No injuries were reported during the storms Thursday night.
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