Abstract:By using daily, hourly precipitation data of Shandong Province and NCEP FNL (Final) operational global analysis data from 2000 to 2011, and based on the spatial and temporal statistics of physical indicators of rainstorms in Shandong Province, the physical indicators characteristics of rainstorms in different seasons and regions were analyzed. The results show that rainstorms have obvious nighttime enhanced trend. The physical indicators of rainstorms in daily operations have different levels of seasonal change. On one hand, the thresholds of these indicators have significant seasonal differences, for example, the specific humidity indicator is 10 g·kg-1 in April and May but it is only 14 g·kg-1 in July, and on the other hand, the effects of water vapor, dynamic and thermal instability factor on rainstorms are not the same in different seasons. The water vapor factor is usually high, and the dynamic and thermodynamic instability factors are low in summer. Furthermore, atmospheric convective instability can be stronger but baroclinicity gets weakened in summer. However it is contrary to the other seasons. Regional difference of the physical indicators of Shandong rainstorms is not the same as seasonal variations, but it is different among various factors. The rainstorms in the south of Shandong need stronger water vapor, and the thermal instability is also higher, the K index is about 0.5℃ higher than other areas while the rainstorms of east part of Shandong Peninsula have higher dynamic factors. Meanwhile, a wide range rainstorms and regional rainstorm need better moisture conditions, stronger dynamic conditions, but lower convective instability conditions.