Organizing any outdoor event involves checking weather forecasts for conditions that may be considered undesirable. Placing people unnecessarily in the path of lightning is never a wise choice. Being educated on the times of year most prone to lightning storms is helpful. Use common sense. Keeping up with the most current forecast is also a good idea. 

Generally, if you can hear thunder, you are at risk, even if you don't see lightning. Don't risk your safety. Seek shelter when storms roll through the area. 

Updated January 2013