The forecast that worked best for me (at least in summer in Europe) was local sailplane text forecast from the respective national service. It was an interpretation of the model by a very experienced human with a big picture introduction ("this front" or that "high pressure area") and also expressed uncertainties. They are sometimes behind soft paywalls, though (need to register, but its free. There are some weird rules of the EU about some weather data - cannot be freely available. I don't get it)