When Thunder Roars, Go Indoors!
There is little you can do to substantially reduce your risk if you are outside in a thunderstorm. The only completely safe action is to get inside a safe building or vehicle. You are not safe anywhere outside.
Run to a safe building or vehicle when you first hear thunder, see lightning or observe dark threatening clouds developing overhead. Stay inside after you hear the last clap of thunder. Do NOT seek shelter under trees. If you are camping, go to your vehicle! A tent or picnic shelter are NOT safe places.
Listen to your weather station on your radio or check your cell phone for weather forecasts. Always have a emergency lightning safety plan in place especially if you are with a group so you can have extra time to get everyone to a safe place.
If you are stuck outside, avoid water. Seek clumps of shrubs or trees of uniform height. Seek ditches, trenches or the low ground. Seek a low, crouching position with feet together with hands on ears to minimize acoustic shock from thunder.
On the Water
The vast majority of lightning injuries and deaths on boats occur on small boats with NO cabin. It is crucial to listen to weather information when you are boating. If you are out and cannot get back to land and safety, drop anchor and get as low as possible. Large boats with cabins, especially those with lightning protection systems properly installed, or metal marine vessels are relatively safe. Remember to stay inside the cabin and away from any metal surfaces. Stay off the radio unless it is an emergency!
In general, a significant lightning threat extends outward from the base of a thunderstorm cloud about 6 to 10 miles. Thunder can usually be heard at a distance of about 10 miles away depending on background noise. Traffic, wind, and precipitation may limit the ability to hear thunder at that distance. Stop your outdoor activities and go inside a building away from windows and doors and anything that conducts electricity such as corded phones, wiring, plumbing, and anything connected to these. Above all else, don’t kid yourself – you are NOT safe outside.