Common Alerting Protocol (CAP)

The WMO Common Alerting Protocol (CAP) is a universally standardized format for emergency alerts. CAP enables consistent communication across various channels in case of hazards. It allows alerting authorities to share alerts through multiple media ensuring that critical emergency information is accessible to all.

CAP complements existing alerting systems by standardizing multi-hazard early warning dissemination. It enables alerts to reach people through multiple channels simultaneously, increasing the likelihood that critical information is received promptly and effectively.

CAP messages are routed through the WMO Register of Alerting Authorities (RAA), which verifies that warnings originate from recognized, authoritative sources for designated alerting areas.