Coaches, athletic trainers, athletes, administrators and contest officials shall be educated regarding the signs indicating thunderstorm development. Since the average distance between successive lightning flashes is approximately two to three miles, in most cases whenever lightning can be seen or thunder is heard, the risk is already present. However, at night under certain atmospheric conditions, lighting flashes may be seen from distant storms. In these cases, it may be safe to continue an event if no thunder can be heard and the flashes are low on the horizon. Weather can be monitored using the following methods:
- Monitor Weather Patterns – Be aware of potential thunderstorms by monitoring local weather forecasts the day before and the morning of the competition, and by scanning the sky for signs of potential thunderstorm activity.
- National Weather Service – Weather can also be monitored using small, portable weather radios from the NWS. The NWS uses a system of severe storm watches and warnings. A watch indicates conditions are favorable for severe weather to develop in an area; a warning indicates severe weather has been reported in an area, and everyone should take proper precautions. Any thunderstorm poses a risk of injury or death even if it does not meet the criteria for severe weather. Therefore, anytime thunderstorms are in the forecast (even if it is only a 20 percent chance), event organizers shall be at a heightened level of awareness to the potential danger of lightning.
- Evacuation – If lightning is imminent or a thunderstorm is approaching unless under the night atmospheric conditions previously explained, all personnel, athletes and spectators shall evacuate to available safe structures or shelters. A list of the closest safe structures should be announced and displayed on placards at all athletic venues.
- Thirty-Minute Rule – Competition or practice shall be suspended once lightning has been recognized or thunder is heard. It is required to wait at least 30 minutes after the last flash of lightning is witnessed or thunder is heard prior to resuming practice or competition. Given the average rates of thunderstorm travel, the storm should move 10-12 miles away from the area. This significantly reduces the risk of local lightning flashes. Any subsequent lightning or thunder after the beginning of the 30-minute count shall reset the clock, and another count shall begin.
NFHS Policy Change - 2018
At night, under certain atmospheric conditions, lighting flashes may be seen from the distant storms. In these cases, it may be safe to continue an event. If no thunder can be heard and the flashes are low on the horizon, the storm may not pose a threat. Independently verified lightning detection information would help eliminate any uncertainty.