The project HMMCS, abbreviation for the project "High resolution climate modelling with a focus on mesoscale convective systems and associated precipitation over the Third Pole region", was endosed by WCRP-CORDEX as a Flagship Pilot Study (FPS) in 2019. This project aims to enhance our understanding of the water cycle over the TP region; with an initial focus on assessing model skill in the simulation of convection and precipitation, building towards skillful multi-year simulation of the regional precipitation and hydrological regime. There are two working groups (WGs): WGI focuses on modeling and WGII focuses on data. The two WGs will work closely with each other. This project will be carried out during the period 2020-2024.