The COSMO-Model is a nonhydrostatic limited-area atmospheric prediction model. It has been designed for both operational numerical weather prediction (NWP) and various scientific applications on the meso-β and meso-γ scale. The COSMO-Model is based on the primitive thermo-hydrodynamical equations describing compressible flow in a moist atmosphere. The model equations are formulated in rotated geographical coordinates and a generalized terrain following height coordinate. A variety of physical processes are taken into account by parameterization schemes.

The model is installed on a high performance computing cluster system of 184 cores. COSMO is drived by initial conditions from the GME (Global Model of DWD, Germany) which has 20km horizontal grid resolution and 60 atmospheric Levels. COSMO operates daily for 3day(at 00UTC) forecast at 10km horizontal resolution. PMD was previously using High Resolution Regional Model (HRM) of DWD Germany which was hydrostatic model with limitations of very horizontal resolutions for complex topographic domain. The vertical pressure gradient force is set equal to gravity in hydrostatic models. This assumption works well until the grid spacing goes below ~10 km. Non-hydrostatic motions include meso-scale phenomenon mountain waves, thunderstorms, and squall lines which occur inside the grid spacing of hydrostatic models.

Further improvements in the resolution and performance of COSMO model are underway and will further improve the weather forecasts issued by PMD and also enhance the accuracy of weather predictions.