A study of the nowcasting method of lightning activity in thunderclouds by weather radar

Abstract. Several methods of nowcasting thundercloud lightning activities have been presented for the past few decades, using weather charts and/or stability index of upper air profiles. In this paper, the author indicates a new nowcasting method by using weather radar observations and several lightning detection systems. The first lightning discharge occurs about 5 minutes after the moderate echo top reaches the -20 degree of centigrade level, and the peak lightning activity occurs as several cells of strong echo descent from the -10 degree of centigrade level to the 0 degree of centigrade level, respectively. A single flash lightning discharge, “Ippatsu-rai” in Japanese, occurs as the cell of moderate echo descent from -20 to -10 degree of centigrade level to 0 degree of centigrade level (near sea or ground surface).