| Insight into the mechanism of different types of thunderstorms and the features of lightning and radar echo evolvement, exploring the matching relationship between Cloud-to-Ground (CG) flashes and radar echoes, helps targeted improvement of forecasting of thunderstorm and flash point. It also can broaden the prediction ideas. The analysis of three different types of thunderstorms is made with the data of routine meteorological data, NCEP data, Doppler radar data and lightning detection data. Two of the thunderstorms happened in spring, and the other was in summer. It is revealed that:1. Analysis of atmospheric energy structure:(1) V-39diagrams can effectively reveal the atmospheric energy structure characteristics before the the thunderstorm happens. Rotating clockwise of wind direction along with the increase of the height, the’ ultra low temperature’ phenomenon of tropopause and the moisture gradient in the vertical direction respectively provides good dynamic, thermal and moisture condition for thunderstorm. These three phenomena can potentially forecast thunderstorms.(2) The upper atmosphere of the two spring thunderstorms is wet, and lower atmosphere is dry. Dynamic conditions of the two spring thunderstorms are significant, but their thermal conditions are weak Differently, in the’1302’thunderstorm, northeast backflow of low layer has been maintained, and its intensity increase gradually.(3) The ’ultra low temperature’phenomenon of tropopause, rotating clockwise of wind direction along with the increase of the height, and the moisture gradient in the vertical direction both happens in the’1202’and’1108’thunderstorms. Differently, the instability of thermal conditions in summer thunderstorms appears more obvious.2. Comparison of physical diagnosis shows:dynamic suction effect of spring thunderstorms is obvious; thermal effect of summer thunderstorm is strong. The summer thunderstorm is caused by local thermal uplift active.3. Comparison with radar data shows:The echo of’1202’spring thunderstorm appears like the stratocumulus cloud precipitation echo. The echo of’1302’spring thunderstorm shows the characteristics of snow. The echo of’1108’summer thunderstorm shows that this weather process is convective precipitation.Obvious wind shear, warm advection in the low layer, and convergence activities appears in the two spring thunderstorms. The echo of’1108’summer thunderstorm shows the features of local thunderstorm. There is an obvious vortex tube, wind shear and convergence activities in it.RHI echo, especially VCS echo can clearly reflect the three-dimensional flow structure inside the the thunderstorm:There is obvious vertical shear in the two spring thunderstorms; According to the RHI velocity echo, the development stage of summer thunderstorms can be clearly judged.4. Comparison of CG lightning evolution characteristics shows:The CG lightning frequency of the two spring storms is low, but the percent of positive CG lightning is high. The CG lightning frequency of the summer storm is high.It shows multiple peaks. The percentage of positive CG lightning is low. In the mature stage of the storm, radar echo top height and the CG flash rate are negatively correlated, and the echo top height reaches the peak before CGs.5. Analysis of the matching relationships between radar echo intensity and CG distribution of three thunderstorms shows:There is certain corresponding relation between flash points and radar reflectivity. In the stage of development, the CGs can be the guidance of the radar echo. It can be told that CGs mainly occur in the wind shear zones and areas of high speed value through analysis of the matching relationships between radial velocity and CG distribution of three thunderstorms. |
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