The wind-capacity layer uses external 2022 reference data (AEE via Wikipedia), separate from the Kaggle dataset. It’s here to show that Spain’s wind farms cluster in Castilla y León, Galicia and Aragón, well away from these five weather-observation cities. That gap is the reason the link between wind speed and wind generation in the Deep Dive turns out so weak.

The legend in the bottom-left is for the wind-capacity layer (the map doesn’t switch legends when you toggle between the two layers). For temperature, switch to that layer above and hover any city marker to see its exact value.