"Jay Honeck" wrote:
Does anyone know the mechanics behind the funding of Automated Weather
Observation Systems (AWOS) at airports?

Your answer is he
http://www.faa.gov/asos/

"Both Federal and nonfederal systems are in service. The FAA purchased and
currently maintains the Federal AWOS equipment. State, local, and private
organizations buy and maintain nonfederal AWOSs."

So if Iowa has a larger number than average of stations it is probably
because local Iowa governments and organizations are paying for them.