Comparison of Tohoku LLS data and lightning current waveforms in winter

Performance of a lightning location system covering Tohoku region in Japan was validated by comparing the location data and lightning current waveforms observed around a coastal area of the Sea of Japan in 2012 winter. The current waveforms were composed of continuing currents, often superimposed with isolated narrow pulse currents, and pulses. The LLS detected electric field pulses associated with the isolated narrow pulse currents and accurately located their sources, but provided no information on the continuing currents. Peak amplitudes of the isolated narrow pulse currents were slightly underestimated. For current pulses associated with negative ground-to-cloud lightning events, the peak amplitudes were overestimated several times as much as the actual values.