 The Global Flood Awareness System, GLO-FAS, is a new tool designed to help predict flooding in large river basins around the world. The system uses a combination of numerical weather prediction models and hydrologic models to simulate streamflows and identify areas at risk of flooding. Results from the system show that it can accurately detect hazardous events up to one month in advance, providing valuable information to governments and other organizations to prepare for potential disasters. This article was authored by L. Alfieri, P. Burek, E. Dutra, and others.