Satellite imagery

Cloud-image tiles from the AHI instrument on the Japan Meteorological Agency (JMA) Himawari-9 satellite. The data comes through NOAA Open Data. Instrument channels have one scene every 10 minutes and are kept for about 48 hours. The same endpoints serve all 16 raw channels (B01–B16) and 20 derived layers. Coverage is the Earth disk Himawari-9 can see. Outside the disk is transparent.

Shared rules (coordinates, caching, attribution, and full map examples) are in Map tiles.

Data license

• Attribution · Commercial use OK

  AttributionData: JMA Himawari-9 via NOAA Open Data, ExpTech Studio (exptech.dev)

  When you use NOAA product layers such as cloudtop, cloudmask, sst or tpw, add NOAA to the attribution.

Upstream terms

• JMA Himawari-9 (via NOAA Open Data): The terms JMA and NOAA Open Data set for Himawari data also apply.
• NOAA: U.S. government data, generally free of use restrictions; do not imply NOAA endorses your product.

Where to show it, examples and commercial-use requests: Data licensing and attribution.

Authentication

No API Token is required.

Available times

GEThttps://api.core-tnn1.exptech.dev/api/v2/tiles/satellite/{channel}/list

Commercial OK

ServerTNN-1

Path parameters

• channelstringRequired

  Channel 1–16, or a derived-layer name (see Channels and layers below). Only the canonical form is accepted. For example, 13 is valid and 013 is not.

Request

cURL

curl --compressed "https://api.core-tnn1.exptech.dev/api/v2/tiles/satellite/<channel>/list"

JavaScript

const res = await fetch("https://api.core-tnn1.exptech.dev/api/v2/tiles/satellite/<channel>/list");
if (!res.ok) throw new Error(`HTTP ${res.status}`);
const data = await res.json();
console.log(data);

Python

import requests

res = requests.get(
    "https://api.core-tnn1.exptech.dev/api/v2/tiles/satellite/<channel>/list",
    timeout=10,
)
res.raise_for_status()
print(res.json())

Response

200400500

Success (an empty array [ ] when there is no data). Gzip-compressed when the client supports it

[
  1794641400,
  600,
  600,
  600
]

channel is not valid

bad channel

Server error (plain-text error message)text/plain

Try it

Path parameters

channelRequired

API token (optional)

Remember in this browserSend

The token is sent from your browser directly to the API.

Response fields

The response is a delta-encoded array of integers, oldest first, in Unix seconds. See Map tiles for how to decode it. A derived layer returns times when every channel it is built from is present, so a listed time can be drawn.

Field	Type	Description
[0]	integer	Time of the oldest entry, in Unix seconds.
[i]（i ≥ 1）	integer	Gap from the previous entry, in seconds. Add these up to get each time.

Tiles

GEThttps://static.core-tnn1.exptech.dev/api/v2/tiles/satellite/{channel}/{style}/{time}/{z}/{x}/{y}.webp

Commercial OK

ServerTNN-1

Path parameters

• channelstringRequired

  Channel 1–16, or a derived-layer name.

• stylestringRequired

  normal, jma, or bd. This only affects channels 7–16. Use normal for channels 1–6 and for derived layers.

• timeintegerRequired

  Unix seconds. Use a value from the list. Any second inside the same 10-minute window maps to the same scene.

• zintegerRequired

  Zoom level, 0–11. Outside that range the response is a 1 × 1 transparent GIF.

• xintegerRequired

  XYZ tile column.

• yintegerRequired

  XYZ tile row (north to south).

Request

cURL

curl -o output.webp "https://static.core-tnn1.exptech.dev/api/v2/tiles/satellite/<channel>/<style>/<time>/<z>/<x>/<y>.webp"

JavaScript

const res = await fetch("https://static.core-tnn1.exptech.dev/api/v2/tiles/satellite/<channel>/<style>/<time>/<z>/<x>/<y>.webp");
if (!res.ok) throw new Error(`HTTP ${res.status}`);
const blob = await res.blob();

Python

import requests

res = requests.get(
    "https://static.core-tnn1.exptech.dev/api/v2/tiles/satellite/<channel>/<style>/<time>/<z>/<x>/<y>.webp",
    timeout=10,
)
res.raise_for_status()
with open("output.webp", "wb") as f:
    f.write(res.content)

Response

200304400404500

image/webp, 256 × 256, with an alpha channel, lossy or lossless depending on the layer. Includes Cache-Control: public, max-age=300. If z is outside 0–11, the response is a 1 × 1 transparent GIF (image/gif)binary image/webp

If-None-Match matches the ETag. No contentNo response body

channel, style, time, or the coordinates are not valid

bad style

No data for that time: not stored yet, or past the retention window (application/json)

{
  "error": "Data not found for specified timestamp"
}

Server error. The body is a single newlineNo response body

Try it

Path parameters

channelRequired

styleRequired

timeRequired

zRequired

xRequired

yRequired

API token (optional)

Remember in this browserSend

The token is sent from your browser directly to the API.

Channels and layers

channel can be a raw channel number or a derived-layer name. Both accept only the canonical form in the tables below. The wrong case or a leading zero returns 400.

Channels 1-16

channel	Wavelength	Type	What it shows
1	0.47 µm	Visible (blue)	Aerosols, dust, and smoke. Daytime only
2	0.51 µm	Visible (green)	Vegetation. The green channel of true color. Daytime only
3	0.64 µm	Visible (red)	Highest resolution (0.5 km). Cloud texture and surface outlines. Daytime only
4	0.86 µm	Near-infrared	Water is dark and vegetation is bright. Coastlines and flooded areas. Daytime only
5	1.6 µm	Near-infrared	Ice cloud and snow are darker. Separates cloud phase. Daytime only
6	2.3 µm	Near-infrared	Cloud microphysics and hot spots on the surface. Daytime only
7	3.9 µm	Shortwave infrared	Fog and low cloud at night, and fire hotspots
8	6.2 µm	Water vapor	Upper-level water vapor, jet streams, and dry-air intrusions
9	6.9 µm	Water vapor	Mid-level water vapor
10	7.3 µm	Water vapor	Low-level moisture transport
11	8.6 µm	Infrared	Cloud phase and SO₂
12	9.6 µm	Ozone	Stratospheric ozone
13	10.4 µm	Infrared (atmospheric window)	Closest to the actual cloud-top or surface temperature. The most used infrared image
14	11.2 µm	Infrared	Longwave infrared
15	12.4 µm	Infrared	The difference from channel 13 separates dust and volcanic ash
16	13.3 µm	CO₂	Cloud-top height and thin cirrus

Channels 1–6 show reflectance in grayscale (0% transparent to 100% white). There is no image at night. Channels 7–16 have an image day and night. Use style to switch the color scale.

style (channels 7-16 only)

style	Notes
normal	The grayscale JMA usually uses. Colder is whiter: 290 K is transparent, and 208 K is opaque white
jma	Cloud-top emphasis: warmer clouds stay grayscale, and the coldest cloud tops are colored (blue at the warm end, red at the cold end, a continuous ramp)
bd	Dvorak BD curve: a stepped scale for typhoon intensity analysis. Breakpoints at +9, −30, −41, −53, −63, −69, −75, and −81 °C

Channels 1–6 and every derived layer ignore style, but the URL still needs that segment. Use normal.

Derived layers (20)

channel	Contents	Built from	Update
truecolor	True-color RGB (JMA recipe), close to what the eye sees. Daytime only	Channels 3/2/1	10 minutes
naturalcolor	Natural-color RGB: separates ice cloud from water cloud, and vegetation from bare ground. Daytime only	Channels 5/4/3	10 minutes
ash	Volcanic-ash RGB (JMA recipe): volcanic ash and SO₂ plumes	13−15 / 11−13 / 13	10 minutes
dust	Dust RGB (JMA recipe): dust and yellow dust	13−15 / 11−13 / 13	10 minutes
airmass	Air-mass RGB (JMA recipe): dry stratospheric-air intrusions and warm, moist air masses	10−8 / 13−12 / 8	10 minutes
nightmicrophysics	Night-microphysics RGB (JMA recipe): fog and low cloud at night	13−15 / 7−13 / 13	10 minutes
watervapor	Water vapor (6.2 µm). Available day and night	Channel 8	10 minutes
btd_split	Split-window difference: dust and volcanic ash have the opposite sign from ordinary cloud	13 − 15	10 minutes
btd_fog	Fog and low cloud at night	7 − 13	10 minutes
btd_wvirw	Overshooting tops (deep convection)	8 − 13	10 minutes
btd_so2	Volcanic SO₂ and cloud phase	11 − 13	10 minutes
btd_co2	Thin cirrus and cloud height	16 − 13	10 minutes
btd_ozone	Ozone and tropopause folds	12 − 13	10 minutes
cloudtop	Cloud-top temperature (NOAA retrieval), 190–300 K	NOAA cloud-top height product	Hourly
cloudmask	Four-level cloud mask (clear to cloudy)	NOAA cloud-mask product	Hourly
sst	Sea-surface temperature, 271.15–305.15 K	NOAA CoastWatch ACSPO	Hourly
tpw	Total precipitable water, 0–75 mm	NOAA NESDIS Blended TPW	Hourly
ndvi	Vegetation index (B04−B03)/(B04+B03). Cloudy pixels are transparent	Channels 4 and 3, plus the cloud mask	Hourly
ndwi	Water index (B02−B04)/(B02+B04). Cloudy pixels are transparent	Channels 2 and 4, plus the cloud mask	Hourly
mndwi	Modified water index (B02−B06)/(B02+B06). Separates water from built-up areas. Cloudy pixels are transparent	Channels 2 and 6, plus the cloud mask	Hourly

tpw is not available from the public tile host

tpw is registered in the service, and the list endpoint can query it, but the public tile host currently returns 400 for tpw tile requests. This page will be updated when that is opened up.

ndvi, ndwi, and mndwi are top-of-atmosphere indices without atmospheric correction. They are useful for seeing change and extent. They are not calibrated surface quantities.

Advanced examples

Add the latest scene for a channel in MapLibre GL JS: fetch the list, sum it to the latest time, then add the tile URL template as a raster source. Animation works the same way as radar. See Map tiles.

const API = "https://api.core-tnn1.exptech.dev";
const STATIC = "https://static.core-tnn1.exptech.dev";

async function addLatestSatellite(map, channel = "13", style = "normal") {
  const list = await (await fetch(`${API}/api/v2/tiles/satellite/${channel}/list`)).json();
  if (list.length === 0) return null;
  let t = 0;
  for (const v of list) t += v;

  map.addSource("satellite", {
    type: "raster",
    tiles: [`${STATIC}/api/v2/tiles/satellite/${channel}/${style}/${t}/{z}/{x}/{y}.webp`],
    tileSize: 256,
    minzoom: 0,
    maxzoom: 11,
    attribution: "Data: JMA Himawari-9 via NOAA Open Data, ExpTech Studio (exptech.dev)",
  });
  map.addLayer({ id: "satellite", type: "raster", source: "satellite", paint: { "raster-opacity": 0.85 } });
  return t;
}

Notes

• A missing time returns 404 JSON. A 404 is kept for about 10 seconds. Use only times from the list. Scenes older than about 48 hours drop off the list.
• time is aligned to the start of a 10-minute window. Any second in that window returns the same scene.
• Visible channels (1–6), truecolor, naturalcolor, and the index layers have an image only in daylight. The list still includes nighttime. Tiles are transparent on the night side.
• Hourly layers (cloudtop, cloudmask, sst, tpw, and the three indices) usually show up more than 1.5 hours after the instrument channels. When there is no data yet, the list is an empty array [].
• Use normal, jma, or bd for style. gray is the old name of normal. The public tile host rejects it (400).
• An invalid channel or style returns 400. A time, z, x, or y that is not an integer returns 404 (the path does not match).
• On the map, credit the source with the suggested attribution in Data license. When you use cloudtop, cloudmask, sst, tpw, or the index layers, also add NOAA.