Final report not currently available online
Over ten years ago, a lightning bipolar pattern was identified in the Lake Charles, Louisiana region and subsequently it was shown that this pattern occurs throughout the United States. This is a pattern of positive and negative lightning ground flashes that have a separation of approximately 100 km between their contoured flash density centers. These centers move with the storm system, retaining their orientation for up to a day or so. An examination ten years of lightning data for the continental United States has revealed 'hot spots' of positive lightning along the Gulf Coast, which may be identified with the bipolar patterns. In addition, some of the highest values in peak negative currents also occur in this area.
The researchers for this project examined lightning data from the National Lightning Detection Network in real-time and coordinated the observations with the Lake Charles NWS office in order to determine the meteorological conditions responsible for the high positive lightning density and high negative peak currents observed. Forecasters were trained in the use of the new lightning data set available on AWIPS, resulting in improvements to both lightning forecasting and public safety.