Returns the NWS alerts in effect at a point or inside a bounding box, now or at a past instant, optionally filtered to exact event names. Items use the same Alert shape as GET /v1/weather?include=alerts, field for field; fetch the full detail (geometry, affected population) with GET /v1/alerts/{id}.

Location

Exactly one of:

• lat + lon — alerts whose area contains the point. Every match is returned, newest effective first.
• min_lon, min_lat, max_lon, max_lat — alerts whose area intersects the box. The box must have a non-zero area. Results are ordered by severity (Extreme, Severe, Moderate, Minor, then any other value), then soonest expires, and capped at 50. truncated is true when the result reached the cap (50): more alerts may exist, and the ones left out are the lower-priority ones.

There is no pagination.

Filters

• event — exact NWS event names (e.g. Tornado Warning), comma-separated or repeated, at most 20.
• at — RFC 3339 instant in the past. Returns the alerts that were in effect then. Omit it for alerts in effect now. An at the alerts source rejects is a 400 naming the reason. Items returned with at are historical snapshots, each as it stood at that instant. GET /v1/alerts/{id} always returns the alert's current version, so its detail may have changed since (updated, extended or cancelled).

Caching

Successful responses carry Cache-Control: max-age=60, or max-age=3600 with at (a past snapshot does not change). The scope is public for first-party keys and private for partner keys.

Coverage

A point outside the 50 US states and DC returns 404 outside-coverage with next_steps, and so does an area (a bounding box) that touches none of the US domains (CONUS, Alaska, Hawaii). A box that touches one is served as is and may include area outside the US.

Auth

Standard sw-api Bearer auth applies.

{
  "alerts": [
    {
      "id": "urn:oid:2.49.0.1.840.0.d1e1a911ed0a8ca7b56a9e6a3c5d6ba0035c88fb.001.1",
      "event": "Wind Advisory"
    }
  ]
}