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2024 Hennepin County All -Jurisdiction Hazard Mitigation Plan <br />Volume 2 — Hazard Inventory <br />twice a day. CAPE is essentially how potentially explosive the atmosphere is. In essence, where forecasters <br />see high CAPE values, and high-water vapor content in the atmosphere is where expected lightning and <br />thunderstorms are to occur. <br />4.3.5.10. Detection & Warning <br />Currently, there are no official alert or warning products that are issued by the National Weather Service <br />for just lightning. There are, however, certain programs that can be used that have lightning detection. <br />One of the leading lightning detection companies across the United States is Vaisala. Vaisala's Global <br />Lightning Dataset was first launched in September 2009. However, currently there is no way to receive <br />lightning detection data from Vaisala, or other detection sources, without a paid subscription to a specific <br />service. There are also very few, if any, sources that will give you the distinction between cloud to ground <br />lightning, intra-cloud, and cloud to air lightning, partly because the science is just starting to understand <br />how to detect the difference. Hennepin County has installed lightning sensors at select mesonet stations <br />in the Hennepin West Mesonet network which detect lightning strikes within a 20-mile radius. These <br />sensors can provide some information on how close lightning is to cities in Hennepin County. <br />4.3.5.11. Critical Values and Thresholds <br />Although there are not watches or warnings for lightning, by using the detection services that available, <br />one can watch how lighting within a storm is changing. In general, if lightning activity is increasing within <br />a storm, one can infer that the storm is strengthening. If lighting activity is decreasing, one can infer that <br />the storm is weakening. <br />4.3.5.12. Prevention <br />You cannot prevent lightning from occurring, but you can prevent some of the consequences by being <br />aware of when thunderstorms are forecasted as well as being aware of the potential cascading <br />consequences that can accompany the lightning. If a person sees lightning or hears thunder, they should <br />go inside immediately. <br />4.3.5.13. Mitigation <br />While there is no way to prevent lightning from happening, there are mitigation strategies to help protect <br />from the effects of lightning. First is protecting critical facilities and equipment by installing protection <br />devices such as lightning rods and grounding on communications infrastructure, electronic equipment, <br />and other critical facilities. Another way to mitigate for lightning is through educational and awareness <br />programs. Developing brochures to hand out at festivals, or with monthly water bills is one of the popular <br />strategies. Additionally, teaching schoolchildren about the dangers of lightning and how to take safety <br />precautions is another way to reach the parents at home as well. <br />4.3.5.14. Response <br />Quick response when it comes to effects from lightning is crucial. When someone is struck or is affected <br />by a near strike, ground current, first aid and CPR is crucial. However, CPR must continue for a long time <br />because it takes a long time for the heart to beat again, the diaphragm to function, and even longer for <br />the brain to reboot and control vital organ functions. People who go into cardiac arrest from <br />lightning have a 75 percent mortality rate. Quick response is also needed when lighting causes a fire. <br />115 <br />