Why does Scout scream and tell Atticus that the world is ending in To Kill a Mockingbird?

she feared the world would come to an end, because the morning she woke up she saw snow out side. But she had never seen Snow before so it scared her, knowing that there was change out side ( only in the weather) but this could also be the bigger picture around this like because Scout was not used to change that is the society she lived in . she grew up in town who in which did not like change and they found it difficult to make change because they were so used to living in the society they do.
It was snowing
Because it snows in maycomb