Tempo-Spatial Analysis of Hail Precipitation Occurrence Probability in Kermanshah Province

Abstract Natural hazards in different areas each year will be causing great damage. Hail as one of the major climatic hazards, a lot of damage in different parts of the environment, especially agricultural and horticultural products are created. Understanding of tempo- spatial distribution this phenomenon, much to the prevention of damage caused by this phenomenon, it can help. In this study, data on days with hail, in the period 1987 to 2007 and number five synoptic stations in Kermanshah province have been used. Method used in this study, is the Poisson distribution probability. The results showed that the probability of this phenomenon in the growing season of horticultural crops is very high so that the highest percentage and probability of occurrence of this phenomenon, to be in April and then May. In these months, still in early stages of plants and trees in bloom and are very vulnerable. A surveillance zone also showed that the most vulnerable areas of the hail event are the western province (Sarpolzahab station) and in the eastern province of Kermanshah in Kangavar station.