Could you comment on why all the radar noise in the sample image seems to be almost perfectly confined to the eastern half of the US? Is that just an artifact of the time of day (perhaps the sun was setting the in middle of the US at the time)?
I'd love to know more about the neural network too, but I have no experience with them so I'm not even sure what to ask.
The image was generated around 10:30 PM EST, so they hadn't had time to propagate further west.
Regarding neural nets, I have to admit that I didn't have much experience with them either before working on Dark Sky. They do, however, seem to be a little more forgiving than other kinds of classifiers (Support Vector Machines, and the like).
Check out the examples for the FANN C library: http://leenissen.dk/fann/wp/
Or in ruby: https://github.com/tangledpath/ruby-fann
I am a meteorologist and have used radar for nearly thirty years. I have yet to see a foolproof system -- and I've looked for them.