Drought is a complex phenomenon in Agriculture. Its impacts vary greatly since they depend not only on the magnitude, timing, duration, and frequency of rainfall deficits but also on the differing responses of various plants to water stress. The essence of good drought management is to use this range of responses to best advantage. Iran is one of the world’s largest and most productive suppliers of food and fiber. The objective of this study was therefore to gather and analyze standardized information on Role of Early Warning Systems for Sustainable Agriculture for cereals, leguminous and industrial crops in Iran environmental zones. Annual average rainfall (mm.y-1) and ETo (mm.y-1) in stations with very dry climate are 76.56 and 3001.03, respectively, these rates for stations with dry climate are 195.41 mm.y-1 and 2249.44 mm.y-1, for stations with semi dry climate is 343.9 mm.y-1 and 1351.62 mm.y-1, for stations with semi humid climate is 583.8 mm.y-1 and 1153.4 mm.y-1 and for stations with humid climate is 1272.16 mm.y-1 and 949.91 mm.y-1. The maximum and minimum of Annual average rainfall happened in Rasht (1337.5 mm.y-1) and Zabol (57.7 mm.y-1) stations, and the maximum and minimum for Annual average ETo happened in Chabahar (3909.15 mm.y-1) and Anzali harbor (890.6 mm.y-1), respectively.
