About this extreme weather map

This demo combines official public alert feeds from the United States, Canada, Europe, Australia, and Japan into one normalized map. Polygon feeds are rendered as polygons; feed-only or regional products are shown as source or region centroids.

Sources

• United States: NWS active alerts API.
• Canada: MSC GeoMet weather-alerts GeoJSON collection.
• Europe: MeteoAlarm country Atom feeds with CAP-style alert metadata.
• Australia: Bureau of Meteorology anonymous data-feed warning product when available from the edge.
• Japan: JMA warning JSON plus JMA area metadata, displayed at prefecture centroids.

Notes

• This is a visualization demo and not a life-safety alerting system.
• Some agencies publish precise polygons; others publish text or area-code alerts that need separate boundary datasets for exact geometry.
• The Worker refreshes the normalized R2 snapshot every 5 minutes.