Quickstart

Python first; shell and browser versions follow.

Prepare your environment

API keys are issued on request: email support@mobs.ws. There are no accounts. Keep yours in an environment variable such as MOBS_API_KEY. See Authentication.

Shell

python3 -m venv .venv
. .venv/bin/activate
pip install httpx \
  "websockets>=13"
export MOBS_API_KEY="YOUR_API_KEY"

Open the WebSocket

List the airports you want. Send a JSON ping every 20 seconds, or the socket closes after 60 seconds idle. New reports arrive as new_metar_arrived. No reports are sent on connect.

import asyncio, json, os
from websockets.asyncio.client import connect

URL = (
    "wss://mobs.ws/v1/ws/metar"
    "?airports=KNYC,KLGA"
)
token = os.environ["MOBS_API_KEY"]
HEADERS = {"Authorization": f"Bearer {token}"}

async def heartbeat(ws):
    while True:
        await asyncio.sleep(20)
        await ws.send(json.dumps({"action": "ping"}))

async def main():
    async with connect(
        URL,
        additional_headers=HEADERS,
    ) as ws:
        beat = asyncio.create_task(heartbeat(ws))
        try:
            async for text in ws:
                msg = json.loads(text)
                if msg["type"] == "new_metar_arrived":
                    for rec in msg["data"]:
                        print(rec["icao"], rec["raw_metar"])
        finally:
            beat.cancel()

asyncio.run(main())

AUTH="Authorization: Bearer $MOBS_API_KEY"
Q="?airports=KNYC,KLGA"
websocat \
  -H "$AUTH" \
  "wss://mobs.ws/v1/ws/metar$Q"

// Browsers cannot set socket
// headers; use ?token= here only.
const ws = new WebSocket(
  "wss://mobs.ws/v1/ws/metar"
  + "?airports=KNYC"
  + "&token=YOUR_API_KEY"
);
setInterval(
  () => ws.send('{"action":"ping"}'),
  20000
);
ws.onmessage = (e) => {
  console.log(JSON.parse(e.data));
};

Example data · report text elided

{"type":"new_metar_arrived",
 "data":[
  {"icao":"KNYC",
   "raw_metar": "METAR KNYC 092251Z …",
   "obs_time": "2026-11-09T22:51:00+00:00",
   "report_type":"METAR",
   "arrived_at": "<UTC time, ms>"}]}

Optional: backfill the latest report

After connect or reconnect, GET /v1/metar/latest can fill the current latest report per airport. missing lists requested airports with no record. This is optional backfill, not the live product. There is no history endpoint.

import os
import httpx

api_key = os.environ["MOBS_API_KEY"]
r = httpx.get(
    "https://mobs.ws/v1/metar/latest",
    params={"airports": "KNYC,KLGA"},
    headers={"Authorization": f"Bearer {api_key}"},
)
r.raise_for_status()
body = r.json()
for rec in body["data"]:
    print(rec["icao"], rec["obs_time"], rec["raw_metar"])
print("missing:", body["missing"])

AUTH="Authorization: Bearer $MOBS_API_KEY"
curl -s \
  -H "$AUTH" \
  --get \
  --data-urlencode "airports=KNYC,KLGA" \
  "https://mobs.ws/v1/metar/latest"

All examples are not executed and use a placeholder API key or one read from the environment.

Next: Authentication

How to send your API key, scopes, rotation and revocation.

Getting started

METAR API

Coverage

Next: Authentication