Weather Stations outside US used for ET

Hello Rachio Community

I’ve set up my first Rachio a couple of days ago and I’m running a flex daily schedule across 6 zones.
The first thing I did was to compare Rachio’s ET values to those reported by our national weather service which, here in Germany, is the DWD.

I found their values for potential evapotranspiration to be significantly lower than what Rachio reports.
As I understand Rachio uses the closest national weather station for ET calculations, so I checked under Controller Settings → Weather Source (national) and found a single station located on a US airforce base in Wiesbaden, Gemany (ETOU).

Now I suspect this is a US national weather station rather than a German national weather station and I know several other WS that are closer by (some of them on airports if that’s a criterium).

How can I verify which station Rachio actually uses for ET and how can I select a different one?

Thanks so much
Sebastian