What is the effect of the flashback in the first paragraph of "Tornado Watch"?
It clarifies for readers that the family has still not repaired the damage caused in the first tornado.
It helps readers better appreciate the emotional effect of the second tornado on the family.

It explains to readers that Sydney chooses not to recover from the devastation of the first tornado.
It makes readers more empathetic toward Sydney when she expresses her panic as she learns of the second tornado.