have a simple problem: they show you the forecast, but they don’t tell you when it actually changed.

That might sound trivial. It isn’t.

Modern numerical weather prediction (NWP) systems — like ECMWF IFS — produce remarkably accurate forecasts at ~9 km resolution, updated every few hours. The data is already very good.

The problem is not the forecast.

The problem is attention : knowing when a change in that data is actually meaningful.

I didn’t learn that from software engineering. I learned it years earlier, studying chaos theory at the Instituto Balseiro. It was there, working through dynamical systems, that I first encountered a slightly unsettling idea:

A system can be completely deterministic and still be practically unpredictable.

That idea stayed with me.…