A disparaging title given to Gandalf in Rohan, used by King Théoden and echoed by Gríma Wormtongue. It derived from the fact that Gandalf would appear in Edoras only at times of trouble and danger, a fact that Gríma attempted to twist to make Gandalf appear as one who sought out troubles for his own advantage, and offered no help. This later proved entirely false, as Gandalf's actions played a great part in the victory of Rohan against Saruman. As the Wizard rode on to Minas Tirith, he took up the name himself, calling himself (no doubt with a hint of irony) Gandalf Stormcrow to the Men of Gondor he found working to repair the Rammas Echor.

The title appears to be connected to the tradition of seeing crows as harbingers of misfortune, or literally of coming storms. The origins of this tradition are unclear, but it may go back to Greek mythology, where a crow brought bad news to the god Apollo and had its feathers turned black in punishment.