The icon field is deprecated, no longer documented in the API, and also more complicated in practice, as it can mix multiple conditions, e.g. `...{day,night}/rain,30/snow,60?...`. The space of possible icons is also fairly large -- https://www.weather.gov/forecast-icons to get an idea -- and it's not clear what short string they all map to. So yeah, in theory you could parse and infer a weather condition out of that link, but as you can see it's pretty hacky and already deprecated. The API should really just return a code or enum (e.g. like a WMO code).

But maybe there's a cleaner way to infer it. PRs are always welcome.