The roof of a Montebello business was ripped off and more than a dozen other buildings were damaged Wednesday by a tornado during another day of severe weather in Southern California.
One person was injured and 11 of the 17 damaged buildings were red-tagged, meaning they're not safe to enter, according to the Montebello Fire Department. Montebello spokesman Michael Chee said the injured woman's injuries were minor and not life-threatening.
Sections of the roof were scattered in a parking lot and on streets around the building. Several cars were damaged.
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"It felt like somebody was hitting the wall with iron bars," a witness told NBCLA. "I saw trash flying around, trees falling down. Even our wrought iron gate is torn up. I'm just thankful no one was injured."
Video from witnesses showed debris moving in a rotating pattern above the building, identified by signs as Royal Paper Box Company. Workers were evacuated from the building. Firefighters entered the damaged buildings, including a Public Storage, to make sure everyone was able to get out.
"We started holding the door, but we couldn't," said Niky Orellana, owner of Niky's Sports Warehouse. "It blew out the door. It blew out the window."
Ariel Cohen, meteorologist in charge at the National Weather Service Los Angeles/Oxnard said crews were still surveying the area to determine the scale of the twister. Cohen said the type of tornado that occurred in Montebello, like others that form in the area, form very quickly.
“Typically, with the tornadoes that affect this area, they spin up very rapidly, unfortunately sometimes too rapidly to detect or warn for. It’s a very different character for the tornadoes that are occurring over the Central and Eastern United States, where there’s a much stronger signal and a slower duration in terms of how they come about to form," he said.
The cell that spawned the severe conditions moved to the northeast, but appeared to weaken as it swept into Covina, Glendora and other communities. The system likely produced rain and small hail as it entered the foothills and mountains.
The National Weather Service was expected to release an official assessment of the severe weather event after visiting the site.
Police advised people to avoid the area of Washington Boulevard from Greenwood to Vail avenues.
The damaging winds followed a day of severe weather that included a tornado warning Tuesday night for central Ventura County and southwestern Los Angeles County. The system was expected to move out late Wednesday, but not before another wave of scattered showers.
No warnings were in place ahead of Wednesday's tornado.
In Carpinteria, the Weather Service confirmed that a tornado damaged a mobile home park in the Santa Barbara County community.
Tornadoes are rare, but not unprecedented in Southern California.
Tuesday's warning was issued 40 years to the month after a tornado packing winds between 113 and 157 mph swept through neighborhoods south of downtown Los Angeles, destroying homes and businesses, flipping cars, hurling debris and ripping part of the roof from the LA Convention Center. Nine people were killed. More than 150 buildings were damaged or destroyed. More than 30 people were injured.
When a tornado warning is issued, anyone in the warning area is advised to move to a basement -- if you happen to have one -- or interior room on the lowest floor of a building. Stay away from windows.
If you're outdoors or in a mobile home or car, it's best to find more substantial shelter and protection from flying debris.