AWOS Funding?

Does anyone know the mechanics behind the funding of Automated Weather
Observation Systems (AWOS) at airports?

I ask this because on our recent flight to St. Louis we were again
struck by the fact that Iowa has a plethora of AWOS, while northern
Missouri has painfully few. See here (select "ALL"):

http://adds.aviationweather.noaa.gov...pletsize=large

Zoom in on Iowa and Missouri. You'll notice that (if you draw a line
from Iowa City [KIOW] to Spirirt of St. Louis [KSUS]) we go through a
relatively large area of empty space. We've come to call this area of
Missouri "The Kirksville Triangle" because the weather always seems to
be bizarre there -- and we can never tell what's ahead due to a lack
of reporting stations.

It's not that there aren't airports there -- there just aren't any
AWOS's.

Is AWOS primarily funded by the states, or is it federally funded?
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"