2014-08-15 / In the Know

In the Know

When thunder roars, head indoors
By B. Michael Thurlow
Special to the Leader

That slogan was developed by the National Weather Service to help raise awareness of the dangers of thunderstorms and lightning by encouraging everyone to go indoors when they hear thunder due to an approaching storm.

Over the past few weeks there seems to have been a rash of severe thunderstorms and even a couple of confirmed tornadoes which occur relatively infrequently in Maine.

It’s a common situation. A thunderstorm is approaching or nearby. Are conditions safe, or is it time to head for safety?

Not wanting to appear overly cautious, many people wait far too long before reacting to this potentially deadly weather threat. Each year across the United States, thunderstorms produce an estimated 25 million cloud-to-ground flashes of lightning – each one of those flashes is a potential killer. Based on cases documented by the National Weather Service over the past 30 years, an average of 73 people are killed by lightning each year and hundreds more are injured, some suffering devastating neurological injuries that persist for the rest of their lives. A growing percentage of those struck are involved in outside recreational activities. When lightning is in the area the sooner activities are stopped and people get to a safe place, the greater the level of safety.

In general, a significant lightning threat extends outward from the base of a thunderstorm cloud about six to 10 miles. Therefore, people should move to a safe place when a thunderstorm is six to 10 miles away.

If thunder can be heard, it’s a safe bet that the storm is within 10 miles.

If the time between lightning and corresponding thunder is 30 seconds or less it would indicate that the thunderstorm is six miles away or less. Activities should also be halted if the sky looks threatening. Thunderstorms can develop directly overhead and some storms may develop lightning just as they move into an area. There is no place outside that is safe in or near a thunderstorm. Consequently, people need to stop what they are doing and get to a safe place immediately. Small outdoor buildings including dugouts, rain shelters, sheds, etc., are not safe. Substantial buildings with wiring and plumbing provide the greatest amount of protection. Office buildings, schools, and homes are examples of buildings that would offer good protection.

Once inside, stay away from windows and doors and anything that conducts electricity such as corded phones, wiring, plumbing, and anything connected to these. In the absence of a substantial building, a hardtopped metal vehicle with the windows closed provides good protection.

Because electrical charges can linger in clouds after a thunderstorm has passed, experts agree that people should wait at least 30 minutes after the storm before resuming outdoor activities.

Most victims can survive a lightning strike; however, medical attention may be needed immediately so call 911 for medical help.

Victims do not carry an electrical charge and should be attended to at once. In many cases, the victim’s heart and/or breathing may have stopped and CPR may be needed to revive them. The victim should continue to be monitored until medical help arrives.

Additional information on lightning and lightning safety is available from the National Weather Service at: http://www.lightningsafety.noaa.gov or by calling the local NWS forecast office in Gray at 688-3216.

If there are any questions about this article or any fire department issue you may contact me at mthurl@ ci.scarborough.me.us or 730-4201. B. Michael Thurlow is fire chief for Scarborough.

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