[Judith Anne]

Okay, ground clutter. I guess, but we are having so much flooding around the southern part of the state, due to the recent 10 inches of rain, that I thought the rural areas would have the ground clutter too...

So, it’s structures that the radar reflects, not ambient moisture. Hmmmm....

Why are the centers empty? Looks like a doughnut.

[buccaneer81]

Why are the centers empty? Looks like a doughnut.

My guess is that the centers are the radar sites.

[stlnative]

speaking of floods...

check this out - click on the map where you want water levels from

http://www.weather.gov/ahps/

[stlnative]

Since you are in MO this site is helpful on which roads are flooded (snow covered, etc) in MO.

http://maps.modot.mo.gov/travelerinformation/TravelerInformation.aspx

[ThePythonicCow]

Why are the centers empty? Looks like a doughnut.

The radar is not looking exactly horizontal. It's situated on the ground looking up at a slight angle, and the earth's surface is falling away, at a slighter angle. So you are looking at an angled cross section of the sky.

In the case say of the donut shape, this means that close to the radar, and really close to the deck, the sky was clear. A little further out, and higher up, there was enough to reflect back to the radar. Further out and higher up still, clear again.