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It has been a longstanding problem for current weather/climate models to accurately predict summer heavy precipitation
over the Yangtze-Huaihe Region (YHR) which is the key flood-prone area in China with intensive population and
developed economy. Large uncertainty has been identified with model deficiencies in representing precipitation processes
such as microphysics and cumulus parameterizations. This study focuses on examining the effects of microphysics
parameterization on the simulation of different type of heavy precipitation over the YHR taking into account two different
cumulus schemes. All regional persistent heavy precipitation events over the YHR during 2008-2012 are classified into
three types according to their weather patterns: the type I associated with stationary front, the type II directly associated
with typhoon or with its spiral rain band, and the type III associated with strong convection along the edge of the
Subtropical High. Sixteen groups of experiments are conducted for three selected cases with different types and a local
short-time rainstorm in Shanghai, using the WRF model with eight microphysics and two cumulus schemes. Results show
that microphysics parameterization has large but different impacts on the location and intensity of regional heavy
precipitation centers. The Ferrier (microphysics) –BMJ (cumulus) scheme and Thompson (microphysics) – KF (cumulus)
scheme most realistically simulates the rain-bands with the center location and intensity for type I and II respectively. For
type III, the Lin microphysics scheme shows advantages in regional persistent cases over YHR, while the WSM5
microphysics scheme is better in local short-term case, both with the BMJ cumulus scheme.
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