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Sherburne County Multi -Hazard Mitigation Plan, 2020 hazard posed by lightning is significant. High winds, rainfall, and a darkening cloud cover are the warning signs for possible cloud -to -ground lightning strikes. While many lightning casualties happen at the beginning of an approaching storm, more than half of lightning deaths occur after a thunderstorm has passed. Lightning can strike more than io miles from the storm in an area with clear sky above. Lightning strikes the ground approximately 25 million times each year in the U.S. According to the NWS, the chance of an individual in the U.S. being killed or injured by lightning during a given year is i in 240,000 (NOAA National Severe Storms Laboratory, n.d.). Lightning is the most dangerous and frequently encountered weather hazard that most people in the United States experience annually. Lightning is the second most frequent killer in the U.S., behind floods and flash floods, with nearly ioo deaths and 500 injuries annually. The lightning current can branch off to strike a person from a tree, fence, pole, or othertall object. In addition, an electrical current may be conducted through the ground to a person after lightning strikes a nearby tree, antenna, or othertall object. The current may also travel through power lines, telephone lines, or plumbing pipes to damage property or cause fires. Lightning History in Sherburne County A 27-year dataset revealed cloud -to -ground lightning strikes occur on average 2,333 times per year in Sherburne County, or 5.2 strikes per square mile (NOAA NCEI). The NCEI Storm Events Database, which records lightning events resulting in injury, death, or damages, reported one lightning event in Sherburne County between 3.996 and July of 203.9. This incident occurred in September of 2005 when lightning struck an empty home in Elk River, starting a fire that destroyed two bedrooms and a garage The total property damage is unknown. To determine the probability of future lightning events in Sherburne County, all past -observed lightning events and the period in which they occurred were examined. Based on the records in the NCEI Storm Events Database, the relative frequency of lightning events in the County is .04 events per year. This relative frequency can be used to infer the probability of these events occurring in the future. Lightning and Climate Change The projected possible intensity and frequency of tornadoes, hail, and damaging thunderstorm winds, the conditions associated with lightning, are uncertain (National Climate Assessment Development Advisory Committee, 2013). Severe rain events are becoming more common and may include an additional risk of lightning. Vulnerability The magnitude of summer storms each year is unpredictable and within Sherburne Countythe vulnerability ofjurisdictions to lightning does not vary geographically. As with all summer storms, those who work outdoors or do not have permanent housing are most at risk. Sherburne County Emergency Management identified that there are existing program gaps and deficiencies that make its citizens more vulnerable to summer storms (includes lightning) and should be addressed with new mitigation efforts to reduce vulnerability. They include: Page149