Radar Images

Access Restriction

This API is a premium service available only to enterprise tier developers. Please contact Caiyun Sales to purchase.

Visualization

Create map overlays from the image bounds returned by the API.

The bounds use WGS84 coordinates in [southLat, westLng, northLat, eastLng] order. Convert the four corners to GCJ-02 before overlaying them on a GCJ-02 base map. WGS84 and Web Mercator base maps can use the bounds directly. Composite images for level=2 are generated in EPSG:3857 / Web Mercator.

Observations

Request

GET http://api.caiyunapp.com/v1/radar/images

Query Parameters

Name	Required	Default	Range	Description
token	Yes	—	—	API token; see Authentication
lon	Yes	—	—	Longitude
lat	Yes	—	—	Latitude
level	Yes	—	1, 2	1 for a station image; 2 for a composite image
world_map	No	—	true, false	With level=2, use true to select the newer composite

Request Example

curl "http://api.caiyunapp.com/v1/radar/images?lon=116.427301&lat=39.902451&level=1&token={token}"

• level=1: 20 recent station-observation frames at 4–6 minute intervals.
• level=2: 20 composite frames at 5-minute intervals. Add world_map=true to use the newer composite.

Response Example

{
  "status": "ok",
  "timezone": "Asia/Shanghai",
  "tzshift": 28800,
  "station": "NMIC_AZ9010",
  "images": [
    [
      "http://cdn-s.caiyunapp.com/weather/radar/color/AZ9010_1640780414_1640780414_ab4b91d31f3f45bca005040f96f42041.png?auth_key=xxx",
      1640780414,
      [
        37.742471186275736,
        113.78227438031607,
        41.874723213724266,
        119.16149781968394
      ]
    ],
    // ...
    [
      "http://cdn-s.caiyunapp.com/weather/radar/color/AZ9010_1640787254_1640787254_20dfc4f347324034af83912a3f94346c.png?auth_key=xxx",
      1640787254,
      [
        37.742471186275736,
        113.78227438031607,
        41.874723213724266,
        119.16149781968394
      ]
    ]
  ]
}

Response Fields

JSONPath	Type	Description
$.status	string	Request status
$.timezone	string	Time zone name
$.tzshift	number	UTC offset in seconds
$.station	string	Radar station or composite ID
$.images	array<array>	Radar image entries
$.images[][0]	string	Image URL
$.images[][1]	number	Image timestamp
$.images[][2]	array<number>	Image bounds in south, west, north, east order

Forecast

Request

GET http://api.caiyunapp.com/v1/radar/forecast_images

Query Parameters

Name	Required	Default	Range	Description
token	Yes	—	—	API token; see Authentication
lon	Yes	—	—	Longitude
lat	Yes	—	—	Latitude
level	Yes	—	1, 2	1 for a station image; 2 for a composite image
world_map	No	—	true, false	With level=2, use true to select the newer composite

Request Example

curl "http://api.caiyunapp.com/v1/radar/forecast_images?lon=116.427301&lat=39.902451&level=2&token={token}"

• level=1: the latest station observation plus a two-hour forecast, 25 frames total at 4–6 minute intervals.
• level=2: 25 composite frames at 5-minute intervals. Add world_map=true to use the newer composite.

Response Example

{
  "status": "ok",
  "station": "CN03",
  "images": [
    [
      "http://cdn.caiyunapp.com/weather/radar/o/cnmap_merca_202112291420_202112291420_3d6ffbaed7.png?auth_key=xxx",
      1640787600,
      [3.9079, 71.9282, 57.9079, 150.6026]
    ],
    // ...
    [
      "http://cdn.caiyunapp.com/weather/radar/o/cnmap_merca_202112291420_202112291620_3d6ffbaed7.png?auth_key=xxx",
      1640794800,
      [3.9079, 71.9282, 57.9079, 150.6026]
    ]
  ]
}

Response Fields

JSONPath	Type	Description
$.status	string	Request status
$.station	string	Radar station or composite ID
$.images	array<array>	Radar image entries
$.images[][0]	string	Image URL
$.images[][1]	number	Image timestamp
$.images[][2]	array<number>	Image bounds in south, west, north, east order

Observation Grid

Access Restriction

This API is a premium service available only to enterprise tier developers. Please contact Caiyun Sales to purchase.

Three files are available:

1. precipitation intensity;
2. availability mask;
3. precipitation-type mask.

File names use UTC. The feed provides the 10 most recent frames (45 minutes of history plus the latest frame) and updates every 5 minutes.