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NOAA National Weather Service API

Free US National Weather Service API with no key: official forecasts, active severe weather alerts, radar stations and observations. Government source. Tested.

No API key requiredCORS enabledHTTPSFree tier

Endpoint tested and returned HTTP 200 on 2026-08-20

What is the NOAA National Weather Service API?

The NOAA National Weather Service API is a free, key-free US government API providing official weather forecasts, active severe weather alerts and warnings, station observations and radar data for the United States.

This is the authoritative source for US weather — the same data behind official warnings — and it is entirely free with no key. Its severe weather alerts endpoint is the one that matters most: tornado, flood and hurricane warnings straight from the issuing authority.

The API is discovery-based, which surprises people. You do not request a forecast by coordinates directly; you call `/points/{lat},{lon}` first, and it returns URLs for that location's forecast, hourly forecast and observation stations. Two requests, always.

Quick facts

Base URL
https://api.weather.gov
Authentication
No API key. NWS asks for a User-Agent with contact details so they can reach you about problems.
Rate limit
No published hard limit; a reasonable use policy applies.
Pricing
Free public domain US government data.
CORS
Enabled — callable directly from browser JavaScript
Official docs
Read the docs

How to use the NOAA National Weather Service API

Every request below was executed against the live API on 2026-08-20, and the response shown is the real body it returned — not an illustration.

1. Look up forecast endpoints for coordinates

GET https://api.weather.gov/points/39.7456,-97.0892

curl
curl 'https://api.weather.gov/points/39.7456,-97.0892'
JavaScript (fetch)
const res = await fetch("https://api.weather.gov/points/39.7456,-97.0892");
if (!res.ok) throw new Error(`Request failed: ${res.status}`);
const data = await res.json();
console.log(data);
Python (requests)
import requests

res = requests.get("https://api.weather.gov/points/39.7456,-97.0892", timeout=20)
res.raise_for_status()
print(res.json())
Response — HTTP 200 (truncated)
{
  "@context": [
    "https://geojson.org/geojson-ld/geojson-context.jsonld",
    {
      "@version": "1.1",
      "wx": "https://api.weather.gov/ontology#",
      "s": "https://schema.org/",
      "geo": "http://www.opengis.net/ont/geosparql#",
      "unit": "http://codes.wmo.int/common/unit/",
      "@vocab": "https://api.weather.gov/ontology#",
      "geometry": {
        "@id": "s:GeoCoordinates",
        "@type": "geo:wktLiteral"
      },
      "city": "s:addressLocality",
      "state": "s:addressRegion",
      "distance": {
        "@id": "s:Distance",
        "@type": "s:QuantitativeValue"
      },
      "bearing": {
        "@type": "s:QuantitativeValue"
      },
      "value": {
        "@id": "s:value"
      },
      "unitCode": {
        "@id": "s:unitCode",
        "@type": "@id"
      },
      "forecastOffice": {
        "@type": "@id"
      },
      "forecastGridData": {
        "@type": "@id"
      },
      "publicZone": {
        "@type": "@id"
      },
      "county": {
        "@type": "@id"
      }
    }
  ],
  "id": "https://api.weather.gov/points/39.7456,-97.0892",
  "type": "Feature",
  "geometry": {
    "type": "Point",
    "coordinates": [
      -97.0892,
      39.7456
    ]
  },
  "properties": {
    "@id": "https://api.weather.gov/points/39.7456,-97.0892",
    "@type": "wx:Point",
    "cwa": "TOP",
    "type": "land",
    "forecastOffice": "https://api.weather.gov/offices/TOP",
    "gridId": "TOP",
    "gridX": 32,
    "gridY": 81,
    "forecast": "https://api.weather.gov/gridpoints/TOP/32,81/forecast",
    "forecastHourly": "https://api.weather.

2. Fetch active severe weather alerts for a state

GET https://api.weather.gov/alerts/active?area=CA

curl
curl 'https://api.weather.gov/alerts/active?area=CA'
JavaScript (fetch)
const res = await fetch("https://api.weather.gov/alerts/active?area=CA");
if (!res.ok) throw new Error(`Request failed: ${res.status}`);
const data = await res.json();
console.log(data);
Python (requests)
import requests

res = requests.get("https://api.weather.gov/alerts/active?area=CA", timeout=20)
res.raise_for_status()
print(res.json())
Response — HTTP 200 (truncated)
{
  "@context": [
    "https://geojson.org/geojson-ld/geojson-context.jsonld",
    {
      "@version": "1.1",
      "wx": "https://api.weather.gov/ontology#",
      "@vocab": "https://api.weather.gov/ontology#"
    }
  ],
  "type": "FeatureCollection",
  "features": [
    {
      "id": "https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.32e04cdec4d5b16ce14c437133eb30c06db6345c.002.1",
      "type": "Feature",
      "geometry": null,
      "properties": {
        "@id": "https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.32e04cdec4d5b16ce14c437133eb30c06db6345c.002.1",
        "@type": "wx:Alert",
        "id": "urn:oid:2.49.0.1.840.0.32e04cdec4d5b16ce14c437133eb30c06db6345c.002.1",
        "areaDesc": "Central Siskiyou County Including Shasta Valley; Siskiyou County from the Cascade Mountains East and South to Mt Shasta; Modoc County Except for the Surprise Valley",
        "geocode": {
          "SAME": [
            "006093",
            "006049"
          ],
          "UGC": [
            "CAZ281",
            "CAZ284",
            "CAZ285"
          ]
        },
        "affectedZones": [
          "https://api.weather.gov/zones/fire/CAZ281",
          "https://api.weather.gov/zones/fire/CAZ284",
          "https://api.weather.gov/zones/fire/CAZ285"
        ],
        "references": [],
        "sent": "2026-08-19T11:53:00-07:00",
        "effective": "2026-08-19T11:53:00-07:00",
        "onset": "2026-08-21T14:00:00-07:00",
        "expires": "2026-08-20T00:00:00-07:00",
        "ends": "2026-08-21T21:00:00-07:00",
        "status": "Actual",
        "messageType"

Parameters

ParameterTypeRequiredDescription
points/<lat>,<lon>pathRequiredEntry point — returns URLs for that location's data. points/39.7456,-97.0892
alerts/activepathOptionalAll active weather alerts, filterable by area. alerts/active?area=TX
gridpoints/<office>/<x>,<y>/forecastpathOptionalThe forecast URL returned by /points. gridpoints/TOP/31,80/forecast
User-AgentheaderOptionalContact details, requested by NWS policy. MyApp (you@example.com)

Response fields

properties.forecaststring
URL for the multi-day forecast for this location.
properties.forecastHourlystring
URL for the hourly forecast.
properties.observationStationsstring
URL listing nearby observation stations.
properties.gridId / gridX / gridYstring|integer
The NWS forecast grid cell for these coordinates.
properties.relativeLocationobject
Nearest named place, useful for display.
(alerts) properties.severity / eventstring
Alert severity and event type such as Tornado Warning.

What you can build with the NOAA National Weather Service API

  • Display official US forecasts and severe weather warnings
  • Trigger alerting when a warning is issued for a user's area
  • Access raw observation data from NWS stations
  • Build emergency preparedness tools with authoritative data

Common errors and how to fix them

404 on /points

Coordinates are outside US territory.

Fix: The NWS API covers the United States and its territories only.

Expected a forecast but got URLs

The /points endpoint is a discovery step.

Fix: Follow properties.forecast to the actual forecast — it always takes two requests.

Excessive coordinate precision rejected

NWS truncates to four decimal places.

Fix: Round coordinates before requesting.

NOAA National Weather Service API — frequently asked questions

Is the National Weather Service API free?

Yes, completely free with no API key. It is US government public domain data, and NWS only asks that you send a User-Agent with contact details.

Why doesn't /points return a forecast?

It is a discovery endpoint. It returns the URLs for that location's forecast, hourly forecast and stations, which you then follow — so a forecast always takes two requests.

Can I get severe weather alerts?

Yes, /alerts/active returns current warnings and watches, filterable by state or zone. This is the official source used for public warnings.

Does it cover outside the US?

No. Coverage is the United States and its territories. Use MET Norway or Open-Meteo for global forecasts.

Tools that pair with this API

NOAA National Weather Service is an independent third-party service and is not affiliated with ByteTools or ByteVancer. Details on this page were verified on 2026-08-20; always check the official documentation before relying on this API in production, as terms and limits can change.