Early warning systems (EWSs) are widely recognised as one of the most effective disaster risk reduction measures as they have the potential to save lives, protect livelihoods, and minimise economic losses. Through the Early Warnings for All (EW4All) initiative, the United Nations aims to ensure universal protection through multi-hazard early warning systems (MHEWS), which move beyond single-hazard warning systems. This is occurring alongside a global transformation where national meteorological and hydrological services (NMHS) are shifting from traditional hazard-based forecasting to impact-based approaches that enable early warning early action (EWEA) and anticipatory action. Yet, despite the growing recognition of the importance of EWSs, significant gaps persist between global ambitions, operational realities, and documented science.

This special issue aims to advance the field of EWSs and focuses on practical implementation, multi-hazard and impact-based integration, innovation, and evidence from operational EWSs. We are particularly interested in contributions that move beyond conceptual frameworks and that demonstrate how EWSs can effectively forecast (multiple) hazards and their interrelationships while taking the vulnerabilities and coping capacities of diverse populations in real-world settings into account and by enabling early action.

Review process: all papers of this special issue underwent the regular interactive peer-review process of Natural Hazards and Earth System Sciences handled by members of the editorial board as well as guest editors designated by the NHESS executive editors.