THUNDER: With spring on the way, we’ve been doing some searching to learn more about the dangers of thunderstorms. Farmers Almanac has been a great resource.

During a thunderstorm, each flash of cloud-to-ground lightning is a potential killer. The determining factor on whether a particular flash could be deadly depends on whether a person is in the path of the lightning discharge. In addition to the visible flash that travels through the air, the current associated with the lightning discharge travels along the ground. Although some victims are struck directly by the main lightning bolt, many victims are struck as the current moves in and along the ground. While virtually all people take some protective actions during the most dangerous part of thunderstorms, many leave themselves vulnerable to being struck by lightning as thunderstorms approach, depart, or are nearby.

An Approaching Thunderstorm: When Should I Seek Shelter?

Lightning can strike as much as 10 miles away from the rain area in a thunderstorm. That’s about the distance you can hear thunder. When a storm is 10 miles away, it may even be difficult to tell a storm is coming. The first stroke of lightning is just as deadly as the last. If the sky looks threatening, take shelter before hearing thunder.

Use the 30-30 rule where visibility is good and there is nothing obstructing your view of the thunderstorm. When you see lightning, count the time until you hear thunder. If that time is 30 seconds or less, the thunderstorm is within 6 miles of you and is dangerous. Seek shelter immediately. The threat of lightning continues for a much longer period than most people realize. Wait at least 30 minutes after the last lightning flash before leaving shelter. Don’t be fooled by sunshine or blue sky!