Why dish tv doesn't work in rainy season?

Satellite Television is broadcast from a satellite orbiting above the equator. Anything in its path can reduce the level that is received at the receiver. If your reception seems to drop off even when there is no visible weather problem (look at the clouds) and happens often, look a different problem. This is often a tree that has grown and has leaves in the path from the dish to the satellite. If this isn't obvious, call Dish Netowrk to get the dish checked. Most likely it has shifted enpough that you are only getting a marginal signal and it needs to be re-adjusted.