A lot of forest fires just starting are actually reported by small airplane pilots who notice them from the air. The controllers pass the information along to the proper authorities very quickly. I've reported a few. I note that half an hour later, there is already a response. So I guess NorCal approach calls the right people pretty quickly. So in a way, this is already being done.

Well, there are satellites that have far larger fields of view, so the question is how much smaller fires you can see with a blimp compared to a satellite.