We just had a nice summer rainshower - 40 mm.
WD showed the rain-icon and after a few minutes it showed the thunder-icon half over it. I must check the size of each icon, because I think that’s the reason they overlap wrong. But besides that, how does WD know that there is actually a thunderstorm? Is it calculated, because I don’t remember to have installed a censor for that?? :?
Peter Palm,
Are you by any chance using an airports metar to update you forecast condition? If you are many times this can come from the metars heading.
No, I have not set that up, Rupp.
That’s why I was wondering 
Hum… I’ll bet then it’s derived from the rain rate.
it just assumes that if you have really heavy rain, its from a CB cloud, which may or may not produce lightning