analyzing and zoning of temporal and spatial features of frost regions in iran

in this paper the minimum temperatures of 54 weather stations collected for a 31-year period were analyzed for zoning the frost regions in iran. the results of this study show that the average of the number of frost days per year was 62, and the average temperature was 3 degrees of centigrade below zero. dey the tenth month in the iranian calendar, december 22-january 20 with an average of 28, had the most frost days and the lowest temperatures. the most frosted days with severe temperature points belong to january with the average of less than 30 days. the regions of west, north west and the alborz were the most highly frosted ones, while northern parts experienced less severe frosts. in all the periods, west, north west and southern sides of the alborz had the highest average and lowest temperatures, whereas northern and southern regions had the lowest average and highest temperatures.