Tsunamis

Last modified: 7/27/2026

Tsunamis

A tsunami is a series of ocean waves generated by the sudden displacement of a large volume of water — most often by a submarine earthquake, but also by landslides, volcanic eruptions, or coastal collapse. In the open ocean the waves are barely noticeable; as they reach shallow water near shore they slow and pile up, and can arrive as a fast-rising surge many meters high.

Active Warnings & Advisories

Live U.S. tsunami messages from the NOAA/NWS Tsunami Warning Centers, ingested via the platform feeds addon and rendered from the record store at view time (no page churn).

[DataFeed: no records for feed 'tsunami-alerts']

If nothing renders above, no tsunami messages are currently active — or the tsunami-alerts feed source is not yet configured (see Configuration).

Alert Levels

Level Meaning
------- ---------
Warning Dangerous coastal flooding and powerful currents likely or underway. Move to high ground.
Advisory Strong currents or waves dangerous to those in or near the water. Stay out of the water.
Watch A distant earthquake may later cause a tsunami; stay alert for updates.
Information A minor or distant event; no action needed for most coasts.

Data Sources

Source Provider Coverage
-------- ---------- ---------
Real-time alerts NOAA/NWS via api.weather.gov U.S. coasts, Pacific, Caribbean
Historical events NOAA NCEI / WDS Global Historical Tsunami Database Global, 2100 BC–present
Source earthquakes USGS Earthquake Hazards Program Global, near-real-time

Configuration

The live feed is served by the ngdpbase feeds addon (#685). Enable it and declare the source in the instance app-custom-config.json, then restart:

{
  "ngdpbase.addons.feeds.enabled": true,
  "ngdpbase.addons.feeds.sources": {
    "tsunami-alerts": {
      "adapter": "geojson",
      "url": "https://api.weather.gov/alerts/active?event=Tsunami%20Warning,Tsunami%20Advisory,Tsunami%20Watch",
      "type": "WarningAlert",
      "schemaType": "Article",
      "intervalMinutes": 10,
      "recordIdField": "id",
      "map": {
        "event": "properties.event",
        "severity": "properties.severity",
        "area": "properties.areaDesc",
        "effective": "properties.effective",
        "expires": "properties.expires",
        "headline": "properties.headline",
        "url": "id"
      }
    }
  }
}

type is the domain label (WarningAlert); schemaType stays Article — the WarningAlert/Event schema.org union types are not yet implemented by the framework (ngdpbase#762).


Status: page and feed wiring live. For live data outside this instance visit tsunami.gov and ngdc.noaa.gov/hazard/tsu_db.shtml.