[shmageggy]

Looks like it will be free and open

> We’ll be releasing our model’s code, weights, and forecasts, to support the wider weather forecasting community.

https://deepmind.google/discover/blog/gencast-predicts-weath...

[boringg]

> "We'll soon be releasing real-time and historical forecasts from GenCast, and previous models, which will enable anyone to integrate these weather inputs into their own models and research workflows."

They will give you the weights and code not the forecast - your quote is incomplete.

Its either a temporary gift to the community until its adopted then charge for it OR they know most orgs can integrate that into their products therefore requiring to buy google products IF it works as they say it does.