In the Land of Stories series, she makes 2 prophecies:
The Enchantress Returns
"Of the four travelers, one will not return."
Prophecy made to Alex, who assumes it means one of her traveling companions on the Granny may die or get left behind. In the last chapter of the book, it is revealed that the Snow Queen meant the four travelers from the Otherworld; Alex, Conner, Charlotte and Dr. Bob; Alex will stay in the Land of Stories.
A Grimm Warning
The Snow Queen tells one of her polar bears that she foresees that the Masked Man's identity "will soon be revealed to the person he most wishes to keep it secret from"; this happens when Alex sees him without his mask at the end of the book.