Weather · head-to-head
7Timer! vs Hong Kong Observatory
7Timer! generates numerical weather forecasts from NOAA/NCEP's Global Forecast System across roughly 1.5 million global grid points, refreshed four times daily. Beyond standard meteorological fields (cloud cover, temperature, wind, precipitation), it produces astronomy-specific products like "astro seeing" and atmospheric transparency for stargazing/observation planning, with forecast ranges from 3 days (ASTRO) up to a 9-16 day overview product.
The Hong Kong Observatory's Open Data API exposes roughly 50 machine-readable datasets covering real-time weather observations, 9-day forecasts, lightning counts, tropical cyclone tracking, tidal predictions, UV index and radiation levels, plus historical rainfall and sunshine records, for Hong Kong and nearby waters. It is a free, keyless service built for machine-to-machine consumption, mirrored on the government's data.gov.hk portal alongside the Observatory's own documented endpoint.
| 7Timer! | Hong Kong Observatory | |
|---|---|---|
| Authentication | None | None |
| Pricing | free | free |
| Formats | JSON, XML, PNG | JSON, XML, CSV |
| CORS | no | yes |
| HTTPS | No | Yes |
Hong Kong Observatory supports CORS, while 7Timer! doesn't — pick Hong Kong Observatory for direct browser calls.