An undersea volcano is likely to erupt sometime in 2025. This much advance notice is a big deal, because forecasting eruptions more than hours ahead is “pretty unique,” says geophysicist William Chadwick. But 470 kilometers off the Oregon coast and over a kilometer beneath the waves, a volcano known as Axial Seamount ticks all the boxes that hint at imminent activity, Chadwick and his colleagues reported December 10 at a meeting of the American Geophysical Union in Washington, D.C.