The storm in "The Scarlet Ibis" symbolizes Doodle's weakness and death.
A symbol is something that stands for more than what it is in the story.
“The Scarlet Ibis” is about two brothers. The older one, the narrator, attempts to make his disabled brother Doodle into something he is not. When a storm comes, it blows the scarlet ibis into their lives, and Doodle is obsessed with it. He wants to bury it, and even after his mother forbids him he finds a way.
The bird is unique, like Doodle, but weak, like Doodle. It is special but cannot survive. It has lost its way.
"It lives in the tropics--South America to Florida. A storm must have brought it here." Sadly, we all looked back at the bird. A scarlet ibis! How many miles it had traveled to die like this, in our yard, beneath the bleeding tree.
The narrator, Doodle’s older brother, wants Doodle to be like everyone else. He does not realize that Doodle’s health is failing. In fact, no one seems to. The narrator continues to be ashamed of Doodle, such as when he falls.
I ran as fast as I could, leaving him far behind with a wall of rain dividing us. ... Soon I could hear his voice no more.
In the end, Doodle dies like the bird. He doesn’t belong there either. He is the boy who should not have lived, but did. He should not have walked, but he did. The narrator tried to make him what he was not, and his little body could not take it.