Preliminary Study of Lightning Location Relative to Storm Structure

Lightning is being studied relative to storm structure using a VHP space-time discharge mapping system, radar, a cloud-to-ground flash locator, acoustic reconstruction of thunder, and other instrumentation. The horizontal discharge processes within the cloud generally propagate at speeds of 10-10 m/s. We have found horizontal extents of lightning up to 90 km. In an analysis of a limited number of flashes, lightning occured in or near regions of high cyclonic shear. Positive cloud-to-ground flashes have been observed emanating from several identifiable regions of severe storms. Lightning echoes observed with 10-cm radar are generally 10-25 dB greater than the largest precipitation echo in the storm.