Where did aunt Goldie go during the tornado in story night of twisters?

The book you're referring to is actually called "The Night of the Twisters" by Ivy Ruckman. In the story, Aunt Goldie, who is the protagonist's aunt, stays at home during the tornado.

She initially goes to the basement with her family, but then decides to stay upstairs and watch the storm unfold. While the family believes she's gone to the cellar, she stays in the living room.

This decision is driven by her belief that the family's house is safe and that she can better help them if she stays upstairs. However, this leads to a terrifying moment where she is separated from the family during the storm and they fear she is lost.