Characters referring to tornadoes by the F scale, which ended in 2007 and was replaced by the EF scale.
At about 1h 1 min, when Deb's phone shows the message "No Signal," five reception bars (indicating a good signal) are clearly visible on her phone screen.
The family runs into a shed as a tornado passes through Dublin, Texas... but - afterward - when the father exits the shed, a saguaro cactus can be seen next to the shed door. Saguaros are not found anywhere in Texas.