Delta-T Spray Suitability

Agriculture Weather Credits / request: 3

Computes Delta-T from temperature and relative humidity and flags ideal / caution / unsuitable hours for spraying. Not a prescription.

GET https://api.apikodu.com/api/v1/agriculture/deltat

Documentation

Overview

Computes Delta-T (dry − wet bulb, Stull 2011) from temperature and relative humidity and flags upcoming hours as ideal / caution / unsuitable. Ideal band is typically 2–8 °C. Not a prescription. Weather data © Copernicus ERA5 / ERA5-Land (contains modified Copernicus Climate Change Service information) / Open-Meteo / OpenWeather / MET Norway.

Authentication

Every request requires the x-api-key header. Credits used and remaining quota are returned in response headers (x-api-credits-used, x-api-remaining-credits, x-rate-limit-*).

Request

GET https://api.apikodu.com/api/v1/agriculture/deltat?latitude=39.92&longitude=32.87&hours=48

GET query.

Parameters

Name	Type	Required	Default	Options	Description
`latitude`	number	* Required	—	—	Point latitude -90..90. 0.1° cell.
`longitude`	number	* Required	—	—	Point longitude.
`hours`	integer	Optional	`48`	—	Hours ahead 1–96. Default 48.
`idealMin`	number	Optional	`2`	—	Ideal Delta-T lower threshold °C. Default 2.
`idealMax`	number	Optional	`8`	—	Ideal Delta-T upper threshold °C. Default 8.
`cautionMax`	number	Optional	`10`	—	Caution band upper threshold °C. Above is unsuitable. Default 10.
`includeHours`	boolean	Optional	`true`	`true` `false`	Hourly breakdown. Default true.

Response

Name	Type	Description
`idealHours`	integer	Hours in the ideal band.
`cautionHours`	integer	Hours in the caution band.
`unsuitableHours`	integer	Unsuitable hours (including missing data).
`hoursEvaluated`	integer	Hours evaluated.
`fromTime`	string	First hour UTC ISO.
`toTime`	string	Last hour UTC ISO.
`idealMin`	number	Ideal lower threshold used °C.
`idealMax`	number	Ideal upper threshold used °C.
`cautionMax`	number	Caution upper threshold used °C.
`gridLatitude`	number	0.1° cell latitude.
`gridLongitude`	number	0.1° cell longitude.
`windows`	array	Contiguous ideal hour ranges.
`windows[].fromTime`	string	Window start UTC ISO.
`windows[].toTime`	string	Window end UTC ISO.
`windows[].hours`	integer	Hours in the window.
`hours`	array	Hourly rows when includeHours=true.
`hours[].time`	string	Hour UTC ISO.
`hours[].tempC`	number	Temperature °C.
`hours[].humidityPercent`	number	Relative humidity %.
`hours[].deltaT`	number	Delta-T °C. null when humidity is outside 5–100%.
`hours[].rating`	string	ideal, caution, unsuitable or unknown.
`method`	string	Calculation method: delta-t.
`source`	string	database: tarim_hava cell.
`disclaimer`	string	Decision-support disclaimer. Not a prescription.

Errors

HTTP	code	Description
`400`	`-255`	latitude/longitude missing or out of range.
`400`	`-249`	hours outside 1–96 or invalid threshold order (0 ≤ idealMin < idealMax ≤ cautionMax).
`400`	`-251`	No stored weather cell for this location.
`429`	`-316`	Daily new location (cell) limit (50) reached. Previously requested locations keep working; new locations next day (UTC). Retry-After header gives seconds until end of day.
`503`	`-256`	Cell created; Worker is filling hourly data. Retry in a minute.
`401`	`-100`	x-api-key is missing, empty, malformed, inactive, banned, expired, IP-restricted, or not allowed for this API.
`429`	`-221`	Per-minute request limit exceeded. Response headers: x-rate-limit-limit, x-rate-limit-remaining, x-rate-limit-reset.
`429`	—	Package credit quota cannot cover this request. Body may be { error, limit, currentUsage, requestCost } (no code field).
`500`	`-1`	Unexpected server error. message is a generic error text without technical details.

Notes

Success body is { data: { ... } }. Error body is { code, message }. code is an ApiResponseCode enum value (negative integer).

Sample response

{
  "data": {
    "idealHours": 21,
    "cautionHours": 9,
    "unsuitableHours": 18,
    "hoursEvaluated": 48,
    "fromTime": "2026-08-30T00:00:00Z",
    "toTime": "2026-08-31T23:00:00Z",
    "idealMin": 2.0,
    "idealMax": 8.0,
    "cautionMax": 10.0,
    "gridLatitude": 39.90,
    "gridLongitude": 32.90,
    "windows": [
      {
        "fromTime": "2026-08-30T05:00:00Z",
        "toTime": "2026-08-30T09:00:00Z",
        "hours": 5
      }
    ],
    "hours": [
      {
        "time": "2026-08-30T05:00:00Z",
        "tempC": 17.4,
        "humidityPercent": 71.0,
        "deltaT": 3.1,
        "rating": "ideal"
      },
      {
        "time": "2026-08-30T13:00:00Z",
        "tempC": 31.2,
        "humidityPercent": 28.0,
        "deltaT": 11.8,
        "rating": "unsuitable"
      }
    ],
    "method": "delta-t",
    "source": "database",
    "disclaimer": "Decision support only. Not agronomic advice. Weather data: Copernicus ERA5 / ERA5-Land, Open-Meteo, OpenWeather, MET Norway. Contains modified Copernicus Climate Change Service information. Not a pesticide prescription."
  }
}

Code samples

  
      const response = await fetch('https://api.apikodu.com/api/v1/agriculture/deltat', {
        method: 'GET',
        headers: {
          'x-api-key': 'YOUR_API_KEY'
        }
      });

      const data = await response.json();
      console.log(data);

  
      import requests

      headers = {
          'x-api-key': 'YOUR_API_KEY'
      }

      response = requests.get('https://api.apikodu.com/api/v1/agriculture/deltat', headers=headers)
      print(response.json())

  
      using var client = new HttpClient();
      client.DefaultRequestHeaders.Add("x-api-key", "YOUR_API_KEY");

      var response = await client.GetStringAsync("https://api.apikodu.com/api/v1/agriculture/deltat");
      Console.WriteLine(response);

  
      $response = file_get_contents('https://api.apikodu.com/api/v1/agriculture/deltat', false, stream_context_create([
          'http' => [
              'header' => "x-api-key: YOUR_API_KEY"
          ]
      ]));

      print_r(json_decode($response, true));

  
      curl -X GET 'https://api.apikodu.com/api/v1/agriculture/deltat' \
        -H 'x-api-key: YOUR_API_KEY'

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