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2024 Hennepin County All -Jurisdiction Hazard Mitigation Plan <br />Volume 2 — Hazard Inventory <br />d11;1 ,, Hazard Assessment: LIGHTNING <br />4.3.5.1. Definition <br />Lightning is one of the oldest observed natural <br />phenomena on earth. It has been seen in volcanic <br />eruptions, extremely intense forest fires, surface nuclear��„������ <br />detonations, heavy snowstorms, in large hurricanes, and <br />most commonly, thunderstorms. Lightning is essentially <br />an electrical current where electrostatic discharges <br />between the cloud and the round other clouds within a <br />g io�ll i i <br />cloud, or with the air. Within a thunderstorm, many small,,,,, <br />bits of ice (frozen raindrops) bump into each other as they <br />move around in the air. Those collisions create an electric charge. The positive charges, or protons, form <br />at the top of the cloud and the negative charges, or electrons, form at the bottom of the cloud. Since <br />opposites attract, that causes a positive charge to build up on the ground beneath the cloud. The ground's <br />electrical charge concentrates around anything that sticks up, such as metal conductors, tall buildings, <br />people, or trees. The positive charge coming up from these points eventually connects with the negative <br />charge reaching down from the clouds, and that is when you see the lightning strike. <br />4.3.5.2. Range of Magnitude <br />The magnitude of lightning is incredibly variable from storm to storm. Typically, when discussing <br />magnitude of lighting, one is concerned mostly with lighting strikes that hit the ground. GRAPHICS 4.3.5A <br />and 4.3.5113 are using data from the National Climatic Data Center, which show the reported costs from <br />lightning for the past 10 years. <br />GRAPHIC 4.3.5A <br />Total Damage Cost from Lightning Per Year: Nation Wide <br />109 <br />