Weather Alerts API Reference

Overview

Send a latitude and longitude for the alerts covering one place, or a two-letter state code for everything in effect across the state. Every plan gets the event, severity, urgency, area, timing and safety instructions. Paid plans add the full forecaster description and the warning polygon as GeoJSON, ready to draw on a map.

Live Test Weather Alerts API →

Endpoint

One host, one path per API. The block below shows this call in four languages; every one of them is the same HTTP request. Making requests covers the timeouts, retries and parameter rules that apply to all of them. The SDKs wrap the same call in a typed client.

GEThttps://api.apiverve.com/v1/weatheralerts

1
2

curl "https://api.apiverve.com/v1/weatheralerts?lat=38.627&lon=-90.1994&state=TX" \
  -H "x-api-key: your_api_key_here"

const res = await fetch('https://api.apiverve.com/v1/weatheralerts?lat=38.627&lon=-90.1994&state=TX', {
  headers: { 'x-api-key': 'your_api_key_here' },
});

if (!res.ok) throw new Error(`${res.status} ${await res.text()}`);

const { data } = await res.json();
console.log(data);

import requests

res = requests.get(
    "https://api.apiverve.com/v1/weatheralerts?lat=38.627&lon=-90.1994&state=TX",
    headers={"x-api-key": "your_api_key_here"},
    timeout=15,
)
res.raise_for_status()

print(res.json()["data"])

package main

import (
	"fmt"
	"io"
	"net/http"
)

func main() {
	req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/weatheralerts?lat=38.627&lon=-90.1994&state=TX", nil)
	req.Header.Set("x-api-key", "your_api_key_here")

	res, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}
	defer res.Body.Close()

	out, _ := io.ReadAll(res.Body)
	fmt.Println(string(out))
}

Replace your_api_key_here with the key from your dashboard. When the inputs arrive as a list rather than one at a time, batch requests run up to 200 of them through this same API in a single call.

Authentication

Send your key in the x-api-key header. That is the only auth step — there is no token exchange and no per-endpoint scope to configure. Authentication covers creating, rotating and revoking keys.

401 is the only auth verdict

A 401 means the key is missing, invalid or expired. A 403 means the key is valid but not permitted here — blocked by a key restriction or an IP allow-list. Running out of credits is a 429.

Parameters

Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them.

Parameter	Type	Description
`lat`Optional	number	Latitude of the location to check. Send with lon range -90–90
`lon`Optional	number	Longitude of the location to check. Send with lat range -180–180
`state`Optional	string	Two-letter US state or territory code (e.g., MO) for every alert in effect across it. Used when lat and lon are not sent

Response

Every API returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape. Response format covers the envelope, the other output formats and how premium fields are withheld.

Sample response

{
  "status": "ok",
  "error": null,
  "data": {
    "location": {
      "state": "TX"
    },
    "count": 2,
    "highestSeverity": "Severe",
    "alerts": [
      {
        "id": "urn:oid:2.49.0.1.840.0.f9aca49ebcd46d4148ecadc4f42f00d6fee04ca6.001.1",
        "event": "Flood Warning",
        "headline": "Flood Warning issued October 2 at 1:51PM CDT until October 3 at 2:51AM CDT by NWS Fort Worth TX",
        "summary": "FLOOD WARNING NOW IN EFFECT UNTIL LATE TONIGHT",
        "severity": "Severe",
        "urgency": "Immediate",
        "certainty": "Observed",
        "response": "Avoid",
        "messageType": "Update",
        "area": "Dallas, TX",
        "issuedBy": "NWS Fort Worth TX",
        "sent": "2026-10-02T13:51:00-05:00",
        "onset": "2026-10-02T13:51:00-05:00",
        "expires": "2026-10-03T03:00:00-05:00",
        "ends": "2026-10-03T02:51:00-05:00",
        "description": "...The Flood Warning continues for the following rivers in Texas...\n\nTrinity River At Dallas affecting Dallas County.\n\n* WHAT...Minor flooding is occurring and minor flooding is forecast.\n\n* WHERE...Trinity River at Dallas.\n\n* WHEN...Until late tonight.\n\n* IMPACTS...At 30.0 feet, Minor lowland flooding will begin, and\ntrails along the river begin to flood.\n\n* ADDITIONAL DETAILS...\n- At 1:30 PM CDT Friday the stage was 30.9 feet.\n- Forecast...The river is expected to fall below flood stage this\nafternoon and continue falling to 12.7 feet early Wednesday\nafternoon.\n- Bankfull stage is 30.0 feet.\n- Flood stage is 30.0 feet.",
        "instruction": "Do not drive cars through flooded areas. Caution is urged when\nwalking near riverbanks.\n\nAdditional information is available at water.noaa.gov/wfo/fwd.",
        "geometry": {
          "type": "Polygon",
          "coordinates": [
            [
              [
                -96.93,
                32.75
              ],
              [
                -96.93,
                32.81
              ],
              [
                -96.83,
                32.83
              ],
              [
                -96.71,
                32.75
              ],
              [
                -96.76,
                32.69
              ],
              [
                -96.87,
                32.78
              ],
              [
                -96.93,
                32.75
              ]
            ]
          ]
        }
      },
      {
        "id": "urn:oid:2.49.0.1.840.0.b7cdd851a493afa58b5cf5fc13948ba8a35d2b25.001.1",
        "event": "Flood Watch",
        "headline": "Flood Watch issued October 2 at 1:36AM CDT until October 2 at 7:00PM CDT by NWS Corpus Christi TX",
        "summary": "FLOOD WATCH REMAINS IN EFFECT THROUGH THIS EVENING",
        "severity": "Severe",
        "urgency": "Future",
        "certainty": "Possible",
        "response": "Prepare",
        "messageType": "Update",
        "area": "La Salle; McMullen; Live Oak; Bee; Goliad; Victoria; Webb; Duval; Jim Wells; Inland Kleberg; Inland Nueces; Inland San Patricio",
        "issuedBy": "NWS Corpus Christi TX",
        "sent": "2026-10-02T01:36:00-05:00",
        "onset": "2026-10-02T01:36:00-05:00",
        "expires": "2026-10-02T19:00:00-05:00",
        "ends": "2026-10-02T19:00:00-05:00",
        "description": "* WHAT...Flooding caused by excessive rainfall continues to be\npossible.\n\n* WHERE...A portion of south Texas, including the following areas,\nBee, Duval, Goliad, Inland Kleberg, Inland Nueces, Inland San\nPatricio, Jim Wells, La Salle, Live Oak, McMullen, Victoria and\nWebb.\n\n* WHEN...Through this evening.\n\n* IMPACTS...Excessive runoff may result in flooding of rivers,\ncreeks, streams, and other low-lying and flood-prone locations.\nFlooding may occur in poor drainage and urban areas.\n\n* ADDITIONAL DETAILS...\n- Flooding caused by excessive rainfall is possible. Additional\nrainfall totals of 1-3 inches with isolated higher amounts will\nfall over areas that have already seen 2-4\" of rain within the\nwatch area.\n- http://www.weather.gov/safety/flood",
        "instruction": "You should monitor later forecasts and be alert for possible Flood\nWarnings. Those living in areas prone to flooding should be prepared\nto take action should flooding develop.",
        "geometry": null
      }
    ]
  }
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

Field	Type	Example	Description
`location`	object	`{...}`	The location that was checked: lat and lon, or state
`state`	string	`"TX"`
`count`	number	`2`	Number of alerts in effect
`highestSeverity`	string	`"Severe"`	Severity of the most serious alert (Extreme, Severe, Moderate, Minor or Unknown), or null when there are none
`alerts`	array[2]		Alerts in effect, most severe and most urgent first
`id`	string	`"urn:oid:2.49.0.1.840.0.f9aca49ebcd46d4148ecadc4f42f00d6fee04ca6.001.1"`	National Weather Service identifier for the alert
`event`	string	`"Flood Warning"`	Kind of alert (e.g., Tornado Warning, Flood Watch, Wind Advisory)
`headline`	string	`"Flood Warning issued October 2 at 1:51PM CDT until October 3 at 2:51AM CDT by NWS Fort Worth TX"`	One-line description of the alert with its issue and end times
`summary`	string	`"FLOOD WARNING NOW IN EFFECT UNTIL LATE TONIGHT"`	The forecaster's short headline for the alert, or null when none was given
`severity`	string	`"Severe"`	Extreme, Severe, Moderate, Minor or Unknown
`urgency`	string	`"Immediate"`	Immediate, Expected, Future, Past or Unknown
`certainty`	string	`"Observed"`	Observed, Likely, Possible, Unlikely or Unknown
`response`	string	`"Avoid"`	Recommended action type (e.g., Shelter, Evacuate, Prepare, Avoid, Monitor)
`messageType`	string	`"Update"`	Alert for a new alert, Update for a revised one
`area`	string	`"Dallas, TX"`	Counties or zones the alert covers
`issuedBy`	string	`"NWS Fort Worth TX"`	National Weather Service office that issued the alert
`sent`	string	`"2026-10-02T13:51:00-05:00"`	When the alert was sent, as an ISO 8601 timestamp
`onset`	string	`"2026-10-02T13:51:00-05:00"`	When the hazard is expected to begin, as an ISO 8601 timestamp
`expires`	string	`"2026-10-03T03:00:00-05:00"`	When this message expires, as an ISO 8601 timestamp
`ends`	string	`"2026-10-03T02:51:00-05:00"`	When the hazard is expected to end, as an ISO 8601 timestamp, or null
`description`Premium	string	"...The Flood Warning continues for the following rivers in Texas... Trinity River At Dallas affecting Dallas County. * WHAT...Minor flooding is occurring and minor flooding is forecast. * WHERE...Trinity River at Dallas. * WHEN...Until late tonight. * IMPACTS...At 30.0 feet, Minor lowland flooding will begin, and trails along the river begin to flood. * ADDITIONAL DETAILS... - At 1:30 PM CDT Friday the stage was 30.9 feet. - Forecast...The river is expected to fall below flood stage this afternoon and continue falling to 12.7 feet early Wednesday afternoon. - Bankfull stage is 30.0 feet. - Flood stage is 30.0 feet."	The forecaster's full description of the hazard, where and when
`instruction`	string	`"Do not drive cars through flooded areas. Caution is urged when walking near riverbanks. Additional information is available at water.noaa.gov/wfo/fwd."`	What to do, in the forecaster's words, or null
`geometry`Premium	object	`{...}`	GeoJSON polygon of a storm-based warning, or null for alerts that cover whole zones
`type`Premium	string	`"Polygon"`
`coordinates`Premium	array	`Array of arrays`

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change. Error handling covers the full status list and which of them are worth retrying.

Status	Meaning	What to do
`400`	Input was rejected	Read `error`; it names the parameter.
`401`	Key missing or invalid	Check the header name and the key value.
`403`	Key valid, but not permitted	A key restriction or IP allow-list; see key scoping.
`429`	Rate limited, or out of credits	Read `error` to tell them apart; see rate limits.

Use cases

Field Crew Safety: Dispatch and workforce apps check each job site for active tornado, lightning and flood warnings before sending crews out, and pull workers back when a warning is issued for their location.
Event and Venue Operations: Outdoor venues and event organizers watch for severe thunderstorm and high wind warnings at their exact location to trigger shelter plans and delays early.
Logistics and Fleet Routing: Fleet software checks warnings along delivery stops and depots to reroute around winter storms, flooding and dust storms before drivers reach them.
Property and Home Monitoring: Smart home and property management apps notify owners when a freeze, flood or hurricane warning covers a home so they can act before damage happens.
Weather Apps and Widgets: Weather apps draw storm-based warning polygons on their maps and show the most severe alert first, with the forecaster's own instructions.

Other ways to use Weather Alerts

Set up Weather Alerts on APIVerve, or reach the same source a different way. Your APIVerve account and credits work on all of them — one key, one balance.

Give it to an AI agentConnect over MCP and your agent calls it as a native tool — Claude, Cursor, ChatGPT.VerveKit →Reference →

Google Sheets or ExcelA =VERVE() formula fills a column — no script, no export, recalculates in place.VerveSheets →Reference →

Ground an agent on itA cited, machine-checkable fact your model can't produce on its own.VerveContext →Reference →

Weather Alerts