The National Weather Service confirmed an EF-0 tornado hit Aurora on Thursday afternoon.
A tornado warning was issued and then expired at 4:15 p.m. Thursday for parts of Clackamas County.
The National Weather Service said the EF-0 tornado briefly touched down near the north end of the Aurora State Airport. Peak winds were estimated at 65 to 70 miles per hour.
Firefighters said two small unoccupied planes broke from their tie-downs and flipped over at the Aurora State Airport. Other planes were moved from their original location, but appeared undamaged.
No injuries were reported at the airport.
A large tree broke in half nearby and fell across Boones Ferry Road Northeast, bringing down multiple power lines. PGE crews responded to the scene to remove the lines and restore service.
"It was raining really hard then the rain stopped for a moment," said Smith Gardens manager, Wes Bailey. "It did get this eerie quiet for a moment, then you hear kind of a vacuum suction coming through, then the glass started shattering out of the ceiling and dropping onto the ground."
Smith Gardens in the area sustained damage to multiple glass greenhouses and the main office from the storm. Workers said a tornado touched down and moved across their property.
Bailey said dark clouds washed overhead and when employees spotted a funnel cloud, they ran.
"They watched the system go over the airport and travel towards Canby. My maintenance manager said it was probably 150 to 250 feet wide," Bailey said.
The tornado warning forced the Molalla School District to delay the Molalla Homecoming Parade and keep the high school students secure inside the building.
The thunderstorm that generated this tornado was expected to remain over mainly rural areas of west-central Clackamas County on Thursday evening.
There was also a significant weather advisory for numerous other counties in the Portland metro area.
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