Lightning Risk Reduction Guidelines Outdoors: For Large Groups

The lightning safety plan of action must be known by all event organizers. Event organizers should have a safe location for people to go to in the event of a lightning storm.

Plan Ahead! Make sure the event organizers responsible for safety get a good weather forecast before the event begins.

Safety organizers should have access to real time weather data, either from a dedicated source or the internet. Real time weather information, including cloud to ground lightning data is available (for a fee) from meteorological weather companies. NOAA weather radio also broadcast weather information 24 hours a day, and is a excellent source for general weather forecast and real time severe weather information.

Since it will take considerable time to evacuate people to a safe location, personal observation of the lightning threat may not adequate (especially for fast moving lightning storms). It is recommended that professional lightning detection equipment be made available so that the lightning threat can be observed from significant distances from the event site. Event organizers should know how long it will take to get people to safe shelter.

Even though technology and instrumentation has been proven to be quite effective, it can NOT guarantee safety (especially for storms which develop overhead). However, current lightning detection equipment can be used to observe the location and direction/motion of lightning storms, and can be used to extrapolate their arrival. Detectors also have the added benefit to determine if the threat has ended (remember - it is recommended that an event should not resume until after 30 minutes after the last audible thunder).

When larger groups are involved the time needed to properly evacuate the area increases. As the time requirements increase, the distance at which lightning is noted and considered a threat to move into the area must be increased (remember - it is suggested that people should already be in a safe location when the approaching storm reaches within 5 miles from the events location). It is up to the event organizers to decide how close the lightning can get before warning "alarms" are issued. This will be dependent on storm motion, direction, and the time it will take the people to get to safe shelters.


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