This talk presents a newly developed atmospheric model system, the YOnsei University Research model System (YOURS), which has a great flexibility with multi-platforms with either thread mode or message parallel modes. The dynamical core of the YOURS-Global Spectral Model (GSM) can be either spherical harmonics (SPH) or double Fourier spectral (DFS) (Cheong 2006). The system also has multiple options in each physics parameterization, with newly devised algorithms. This talk introduces the newly developed dynamical core and physics package for weather and climate predictions. Interaction between the boundary layer and precipitation processes is focused.