[scellus]

It's lower than many other medium-range AI forecasts, but note that those other models get state-of-the-art with pretty coarse grids, 0.5° or so. The point is that upper atmosphere and broad patterns are smooth, so with ML/AI they don't require high resolution (while simulating them with physical models does require). And at the forecast lag of say 5-10 days, all local detail is lost anyway, so what skill remains comes from broad patterns, in all models. (Some extra skill can be gained by running local models initialized with the broad patterns, for there are clear cases like mountains where fine resolution is useful.)