Lightning Indicator

I was just watching the weather and some heavy storms are blowing through northern Orlando and Seminole county. The lightning indicator shows a dot, supposedly, where there is a lightning strike. In this case it showed a huge county sized blotch in the Seminole county area, which makes me wonder how accurate that technology is and what is it really showing. The dots were all the same color (color being the time indicator) so they were all very recent. Is it really possible that lightning struck every spot that is covered by the size of the dot?

Anyway, the news said there was extensive lightning in the area. I guess.