Abstract:An analysis is made of lightning flashes during three short duration severe rain events. The results show that: (1) The lightning flashes in three cases were mainly negative, and the ratio of negative lightning flashes to total lightning flashes is over 92%. (2) The lightning frequency peaks were one hour earlier in phase than precipitation peaks. (3) The 5 minute lightning frequency peaks were 5 to 60 minutes earlier than precipitation peaks. (4) The areas with negative lightning flashes concentrated are around the areas with the reflectivity of radar being above 40 dBz; the positive lightning flashes which occurred occasionally distributed in the weak echo areas; lightning flashes occurred mostly in the areas with the echo top being over 5 km and in the wind fields with radial velocity being uneven. The VIL had poor correlation with lightning flashes, and some lighting flashes occur in the areas where VIL is small. (5) Lightning characteristics differ for different clouds; some lightning frequency peaks occurred in the strong echo stage, but some occurred in the weak stage. Sometimes lightning flashes concentrated around or in the front of a strong echo area, which indicates the moving direction of the strong echoes. Some lightning flashes occurred in the developing or mature stage of clouds, and the negative lightning flashes were concentrated near a strong echo area. The lightning flashes were distributed dispersedly in the weakening stage of clouds, concentrated in the different sites.
