Bandali systems (blockings) and atmospheric rivers are important atmospheric phenomena in mid-latitudes. Occurrence of blocking can cause climatic anomalies such as extreme cold, dry periods and heavy rains. Considering the damage caused by heavy rains, it is very important to know the mechanisms governing this phenomenon. Due to its mountainous topography and being in the path of western winds and atmospheric rivers, Iran's plateau is prone to heavy rainfall and dangerous floods. Examining the role of blockings and atmospheric river in the occurrence of heavy rains in the western and southern regions of Iran can play an important role in predicting and managing this phenomenon.