The Post-Dispatch reported:
The National Weather Service said Saturday night that the tornado that hit the Amazon building reached the EF3 category — the third-strongest rating on the Fujita Scale, with winds between 136 miles per hour and 165 miles per hour.
The tornado touched down just northwest of the intersection of Interstates 255 and 270, then traveled northeast into Edwardsville.
The Amazon facility is a "delivery station," where workers prepare orders for delivery by Amazon Flex drivers and partners, the company said. Opened in July 2020, the building totals about 1.1 million square feet and employed about 190 employees in multiple shifts.
The other two Amazon facilities in the area, a fulfillment center and sorting station, are also closed, Amazon said.
Asked about precautions taken, the company said when a facility is made aware of a tornado warning, all employees are told to move to a designated, marked shelter-in-place location. Employees are trained on emergency response, the company said.
I read somewhere that when the sirens went off, the employees had about 11 minutes to seek safety before it hit. I have no idea if they were in the safe area or not.
The photos below were printed in the St Louis Post-Dispatch.