@Dilbert could you read the weather data from a server and pass it to your core using a cloud event ? a standard $5 VPS has an order of magnitude more power than your core, it makes more sense to do processing there.
In my design, each device would take local weather info plus it previous program history to run a algorithm. So that each device will come out with different setting.
I try to make the device can function without depending on Cloud Server after configuration.
Of course, weather server can be done too.