Slide 84 of 95
In recent years, a national lightning detection network has been established that allows forecasters to monitor the number of lightning ground strikes and the polarity of each strike. Information from the lightning detection network is incorporated into public weather warnings and statements to alert people when lightning frequency is particularly high. It has also been observed that storms often exhibit a change in lightning frequency and predominant polarity during the tornado-producing phase. Further research is underway, and lightning ground strike information may become an important tool in the severe thunderstorm and tornado warning process.
Lightning detection network photo of positive and negative ground strikes associated with the Hesston, Kansas, tornado of March 13, 1990, (NOAA/NSSL)