Daily precipitation in Swiss valleys tends to decrease as you go higher up, especially in the south. Only about a third of days see more rain at higher altitudes, with a strong link between rain and altitude. Valleys in the north generally have steeper rain gradients than those in the south, but nearby valleys can differ a lot. Factors like how much rain falls, the weather, region, season, wind, and the land shape don't have a big impact. Where the rain gauges are placed in a valley can change how the rain changes with height.