A rapid increase in inter-cloud lightning may prove a forewarning of an imminent twister
Scientists are becoming increasingly convinced that a rapid increase in inter-cloud lightning—lightning that occurs between clouds without hitting the ground—is a strong indicator of severe weather.
An unassuming-looking rod on a rooftop in Beltsville, Md., connected with wires to specialized computer equipment in the building below, is helping scientists pinpoint the location of lightning as it flashes during a thunderstorm. Working in tandem with nine other identical devices installed throughout the Washington, D.C., area, these sensors promise to help usher in a new era of severe weather prediction.
Called the Washington D.C. Lightning Mapping Array (DC LMA), the devices detect, in real time, high-frequency radio waves emitted by lightning in the surrounding region.
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