Analysis on Characteristics and Causes of 2 Consecutive Days Short-Time Rainstorm in Qingyang
Climate Change Research Letters
Using the Micaps conventional data and regional meteorological stations precipitation observations, the author analyzed circulation background, mesoscale characteristics and physical index of short-time rainstorm in Qingyang from 9 to 11 July 2016. The results are as follows: 1) The short-time rainstorm on 2 consecutive days occurred in the stable continental anticyclone. A convergence at mid-low level was formed by the trough shear line, and a strong divergence in the upper was formed by jet
... was formed by jet on the eastern of South Asia High, and an ascend movement was formed over the rainstorm area by coupling of high-low system. The water vapor convergence and wet layer obviously thickened in Qingyang under the interaction of Typhoon Nepartak and the subtropical high, and the shear line triggered high temperature and high humidity energy, and caused rainstorm weather. 2) The surface mesoscale convergence line was an important factor in triggering rainstorm that corresponded well with short-time strong rainfall. 3) "7.9" rainstorm was caused by mesoscale convective cloud clusters replacement in the precipitation area. Dry intrusion in middle-high level and warm advection at low level were obvious, so that stronger precipitation intensity formed. "7.10" rainstorm was caused by mesoscale convective cloud clusters that were merged into the mesoscale convective cloud zone through precipitation area, so that it had wider range of influence and longer time duration. 4) Through two analysis processes, the author found upper significant cold advection, warm advection at lower environment, stably enhanced high humidity energy, dry and caused unstable stratification were advantageous to short-time rainstorm in Qingyang.