This study demonstrates the characteristics of the Weather Research and Forecasting (WRF) Double-Moment 6-Class (WDM6) Microphysics scheme for representing precipitating moist convection in 3D platforms, relative to the WSM6 scheme that has been widely used in the WRF community. For a case study of convective system over the Great Plains, the WDM6 scheme improves the evolutionary features such as the bow-type echo in the leading edge of the squall line. We also found that the WRF with WDM6 scheme removes spurious oceanic rainfall that is a systematic defect resulting from the use of the WSM6 scheme alone. The simulated summer monsoon rainfall in East Asia is improved by weakening (strengthening) light (heavy) precipitation activity. These changes can be explained by the fact that the WDM6 scheme has a wider range in cloud and rain number concentrations than does the WSM6 scheme. 1. Introduction The Weather Research and Forecasting (WRF) model [1] is a community numerical weather prediction (NWP) model that is applicable to various scales of weather phenomena. Application of the WRF model has recently been extended to resolving regional details embedded within climate signals from the general circulation model [2]. As computer resources become available, the use of high-resolution WRF with a horizontal grid spacing of less than 5？km will improve forecasts for convective-scale phenomena, including explicit information about the timing, intensity, and mode of convection (e.g., [3, 4]). These previous reports demonstrate a 4-km resolution in WRF forecasts, which explicitly resolves convection yields for better guidance in precipitation forecasts, in comparison to 12-km resolution. Microphysical schemes are explicit, whereas convective parameterizations are implicit. As grid spacings decrease, convective parameterizations become more inappropriate (and scientifically questionable given the underlying assumptions), whereas the explicit representation of microphysical processes can be computed for increasingly small clouds, cloud particles, water droplets, and so forth. In the WRF model, there are multiple choices for each physical component; for example, there are ten algorithms for the cloud microphysics scheme, as of August 2009. Among the microphysics packages for clouds and precipitation, the series of the WRF single-moment (WSM) schemes (WSM3, WSM5, and WSM6 [5, 6]) has been widely used. As of June 2009, there are about 50 institutions across the globe running the WRF model on a real-time basis, and many of these institutions chose the WSM scheme for the
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