NWS Weather Alerts MCP Server

NWS Weather Alerts

NWS provides real-time weather alerts (watches, warnings, advisories) by state, county, zone. Data includes event type, severity, certainty, onset/expiry times, affected areas. Alerts follow CAP (Common Alerting Protocol) format.

Data Model

• Alerts — active watches, warnings, advisories with event type, severity (Extreme/Severe/Moderate/Minor/Unknown), certainty (Observed/Likely/Possible/Unlikely/Unknown), urgency.
• Geographic scope — alerts filterable by state (e.g. WA), zone (WAZ001), county FIPS, area, point coordinates, or region.
• Temporal — onset and expiry timestamps, effective time, status (Actual/Exercise/Test).
• CAP format — Common Alerting Protocol fields: headline, description, instruction, sender, category, response type.
• Observations — current weather conditions from NWS stations including temperature, humidity, wind speed/direction, pressure, visibility, and precipitation. Query by station ID (e.g. KLAX, KJFK) or find nearest station from lat/lon coordinates.

Gotchas

• User-Agent required: NWS API requires a User-Agent header identifying the application. Requests without it may be blocked.
• Rate limits: NWS has no published rate limit but requests excessive traffic may be throttled.
• GeoJSON responses: Alert data is returned in GeoJSON format with geometry for affected areas.
• Active only: The /alerts/active endpoint returns only currently active alerts, not historical.