Please excuse my intrusion, I am a geography student and currently trying to put together an economic geography analysis that entails taking a look at “flyable days”. What I am looking for is a yearly average of VFR / IFR days by county for the USA. So essentially this might be important if an aircraft is VFR only and they are based at a foggy airport, it may be common sense to many but from an economic standpoint, geography plays a large roll in aircraft profitability. I am not a pilot so I am learning as I go here. I know there are different levels of IFR/VFR like marginal, etc but this is a class project, not a real high speed publishable study so any help would be great. If anyone might even know where I can get historical county level data on ceiling and vis, that would be cool, I can do the coding myself.
Thank you very much.