This work presents an experimental study on the atmospheric water condensation on micro-grooved substrates. The influence of several physical and geometric parameters (relative humidity, substrate inclination with horizontal, groove size) on the process of condensation and drainage is presented. The process is studied by weighing collected water and visualizing the drops formed on the substrate. The grooves appear to markedly increase the collected amount of water by promoting drop coalescence and lowering pinning forces, resulting in early shedding when compared to a smooth surface with same wetting properties.