Hi Ray, I am using ETo.
I was not aware ETo was using forecast. I will move away from Eto then, as this is too risky.
Nevertheless, Eto reports rain for 7.4mm right now, while all weather forecasts (checked 3 different sources) plan for no rain within the next 5 days (first rain planned for Saturday for 3mm).
As a result, my watering % is now set at 0% while it is super hot with no rain expected before Saturday.