This is the explanation under the radar chart:

"This is a composite plot of the radar summary, echo tops, storm movement, TVS and MESO signatures and watch boxes. NOTE: RCM data is susceptible to a phenomena called anomalous propogation. This generally happens at night and appears as a area of 20 Dbz echos (darkest green) which is centered around each radar site and expands with time. To try and reduce the problem, all radars in clear air mode have been eliminated from the summary. Therefore, some dark green areas at night may not not rain. Please use this in conjunction with satellite imagery to determine whether precipitation is occurring in your area"

I read that as "Ignore this chart. Look out of your window to see if its actually raining"