Met Office Weather DataHub (Site Specific) vs The Weather Company Data APIs

Met Office Weather DataHub (Site Specific)

Statutory UK weather service, with a FAQ licence to copy, publish and adapt the data. No OpenAPI, llms.txt, SDK or MCP server.

The Weather Company Data APIs

A wide weather data API with 168 API references built from OpenAPI documents, global 4 km current conditions, hourly history from June 2015 and a status page with component history. Keys come only through a sales-reviewed trial or contract, travel only in the URL, and the terms that govern the API are not published.

Met Office Weather DataHub (Site Specific)

1. Register an application and subscribe it to the Global Spot plan first. The key is tied to that order and shown once
2. Send the key in the apikey header with Accept: application/json, and latitude and longitude as query parameters
3. Add excludeParameterMetadata=true to drop the parameter descriptions from every response
4. Pick the timestep by need. hourly covers 48 hours, three-hourly 168, daily 7 days, and each call counts against the daily limit
5. Stop on a 429. The limit is daily and resets at 00:00 UTC

The Weather Company Data APIs

1. Send units, language and format=json with a location on every v3 call, plus Accept-Encoding: gzip, which the usage guide marks as required.
2. Keep the key out of logs and client-side code, because it travels in the query string as apiKey.
3. Treat a 401 as either a bad key, an endpoint outside the key's package or an exceeded limit, and treat a 204 as no data for the query.
4. Each forecast duration (3day to 15day) is a separate entitlement. Request only durations the contract covers.
5. Use /v3/aggcommon to combine up to 10 products in one request. Each product and each location still counts as one call.