Hi Sean,
You can customize the weather restrictions now through setting -> preferences -> rain. By default, Netro skip schedules today and tomorrow if today rains more than 0.2 inch. You can customize it, like I want to skip the schedules on the day after tomorrow as well, or I want to skip if rain more than 0.5 inch.
I believe that some of the weather sites use the network of local rain sensors to detect actual rain fall. Could this be used to switch off watering (at least temporarily) until the rain stops?