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Tornadoes Tornadoes are the most violent hazard affecting the planning area. Tornadoes can have an atmospheric pressure differential of 2 inches from the outer edge of the funnel to its center, creating winds in excess of 300 mph across an area as small as 300 yards. For the sake of comparison, a hurricane can have the same pressure differential across an area of 300 miles! Tornado Occurrence per County: 1950-1997 Cheyenne 65 Elbert 51 Kit Carson 71 Lincoln 60 Logan 49 Morgan 50 Phillips 27 Sedgwick 23 Washington 93 Weld 192 Yuma 62 11 County Total 738 The chart above, repeated from the Hazard Identification section, shows that 738 tornadoes have been recorded across the 11 county Planning Area over a 47-year period. At the same time, the chart indicates a wide range of occurrences on a per county basis. The Planning Team believes the data is more indicative of tornadoes being reported versus actual occurrences. The counties with the higher number of occurrences are also those counties with either higher population, greater damages experienced, closer proximity to Interstate Highways, or where official "Spotter Training" has been provided. Additionally, higher numbers of occurrences are reported in counties with the larger land areas. When the randomness of tornado location and the vast open space within the planning area are considered, the Planning Team does not consider anyone area at a greater risk to tornadoes than any other. Thus, the risk of tornadoes is the same across the entire planning area. The risk does not vary from county to county. This is because tornadoes are just as likely to hit one location as another within the planning area. The area that tornadoes strike is random, depending upon the location of the weather system spawning them. The impact of tornadoes is also random across the planning area because of the tremendous amounts of open space between communities and farms and ranches. The planning area frequently experiences tornadoes that strike little or nothing. On the other hand, tornadoes need to be given serious consideration in this assessment, because if and when they do strike populated areas, the impact can be devastating. During the past years of record keeping within the Planning Area there has been one catastrophic incident --- the 1990 Limon Tornado that caused an estimated $25 million dollars of 34