Abstract:To explore the causes for snowstorm with lightning in Henan, the weather situation, effects of upper and low level jets and related quantities which reflect dynamic, thermal and water vapor conditions have been analyzed based on the conventional observations, radar data and NCEP 1°×１° reanalysis data per 6 hours. Results show that the height of inversion layer can reach to higher levels than 600 hPa when a snowstorm with lightning happens. When a frontal zone of instability energy appears at the middle layer of troposphere, it is helpful to the development of ascending motion, which makes the height of cloud increase and the lightning occur. Snowstorm with lightning appears in the vigorous period of upper and 〖JP2〗lower level jets. The center of mesoscale instability is near 800 hPa when lightning happens firstly, while it is between 700 and 650 hPa at the second time. Snowstorm appears at the front of high energy tongue and superimposed area of convective instability. Sustained water vapor transport, the accumulation and confrontation at lower layer of two strong cold air currents and the strong symmetrical instability are the causes for the keep of snowstorm.