Lightning emits radio noise between 5 and 15 kHz, known as sferics, that propagates over thousands of km. A network of five ground based radio receivers situated along the U.S. east coast and Puerto Rico has monitored sferics distributions since July 1997.
Sferics distributions were compared to radar reflectivitity measured by NEXRAD and they appear to occur when the reflectivity exceeds ~40 dBZ. Location accuracy, validated with data from the U.S. National Lightning Detector Network and data from optical lightning sensors on low earth orbiting satellites, depends on the distance from the center of the network. Most thunderstorms have been located within ~50 km over an area of ~ 4 X 107 km2 .
Sferics associated with winter fronts have been observed as they propagated from the eastern Pacific Ocean to the coast of Europe. The evolution of thunderstorms has also been continuously measured between central Brazil to Canada's Northwest Territory.
The 8th Conference on Aviation, Range, and Aerospace Meteorology