Synoptic Analysis of Systems with Heavy and That Cause Flooding Precipitation on the Kashkan Basin for during (1350-1384)

The aim of present study is the synoptic analysis of systems having by heavy precipitation on the Kashkan basin. After study of 34-years statistics from stations for basin and its environments three storms by maximum precipitation were selected. The results of study of weather maps, humidity, earth surface pressure difference and 850 hPa of 48 hours before and after storms, showed that with regard to the fact that three selected storms have out of heavy storms during statistics period occurred in various seasons of the year, their generating system was equal and Sudan-Mediterranean merger system pattern generated maximum precipitation. Synoptic conditions in three chosen storms are: 1-High pressure over Europe northwest and influx of the cold weather in higher latitudes toward low pressure that is situated in east Mediterranean, 2-Sudan low pressure nutrition and motion toward northeast. 3-Days that maximum precipitation has occurred in the basin. These low pressure systems are merged with each other in east of Iraq, and high pressure situated on east of Iran with influx of cold weather over Oman and Arab seas on the one hand and presence of anticyclone in Arabia have caused humidity transfer inside low pressure system situated over west of Iran and generated maximum precipitation.