"Phil Layton" wrote in message ...
Occasionally there is a red inner core
As far as I'm aware the red bit refers to convective (as opposed to frontal)
precipitation, which, as Martin mentioned, is labelled as showers or
thunderstorms.

If you look at the high-resolution GFS output for Europe on the
Wetterzentrale website, you'll see convective rainfall is marked using red
dashes on the precipitation charts.

http://www.wetterzentrale.de/pics/Rmgfs213.gif