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This creates a situation where (a) there are more frequent high winds, and (b) there are more people reporting these events. Secondly, the two groupings extending eastward across the planning area closely follow the routes ofInterstate Highways 1-76 and 1-70. Most communities within the planning area are along these two Interstates, again creating population centers that likely record and report significant wind events. Hail and Severe Summer Storms Hail is formed when water droplets are thrown high into the upper atmosphere by the violent internal forces of thunderstorms. Frequently, hail and tornadoes are associated with severe summer storms, which occur almost daily throughout the spring, summer, and fall within northeastern Colorado. These storms have been identified as a separate hazard because hail is a major cause of agricultural losses within the planning area, as reported by the National Crop Insurance Services. The following table shows the # of times each county has experienced hailstorms with hail 2" or greater in diameter, between 1950 and 2003, a 53 year period. Hail (~ 2") Occurrences per County: 1950-2003 Cheyenne 11 Elbert 7 Kit Carson 13 Lincoln 17 Logan 13 Morgan 17 Phillips 11 Sedgwick 13 Washington 28 Weld 33 Yuma 13 11 County Total 76 Source: National Climatic Data Center Based on the information above, the northeast Colorado planning area has experienced an average of 1.4 significant hailstorms per year. There are no official recurrence intervals calculated for hailstorms. However, using the same methodology that was employed for calculating tornado probability, if one assumes a hailstorm affects one square mile and there are 21,600 square miles in the planning area, the annual probability ofa 2-inch or greater hailstorm hitting any particular square mile in the planning area is 1.4 in 21,600, or a 0.007% (.00007) chance. 19