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Posted at 11:00 AM ET, 06/16/2010

Lightning: To crouch or not to crouch...?

By Don Lipman

* Chance of storms today, hot weekend ahead: Full Forecast *

l17_lincolnlightning3_std-crop.jpg
Lightning at the Lincoln Memorial. By CWG photographer Kevin Ambrose.

Some of you may remember my post from a few weeks ago in which I discussed lightning myths and lightning safety. A particular reader, Michael Utley, who hosts his own website on this subject, was concerned that I advocated the "lightning crouch" as a last resort for lightning protection in an open field, despite the fact that the National Weather Service (NWS) itself suggests this position. He felt that we were endangering lives by doing so. Utley wrote:

Do you really think that going from 6' tall to 4' tall [crouching] is going to make a difference to something [lightning] moving at a couple million miles an hour, 5 times hotter than the sun, with the power of a small power plant, then I have a bridge to show you. In a perfectly flat world, it [crouching] 'MIGHT' make a difference, but there is no 'perfectly flat' place to be.

So what should be done when a thunderstorm strikes suddenly and shelter is nowhere around?

Keep reading for more on the crouching dilemma...

Unfortunately, the answer is not as clear as one would hope. Certainly the old advice, which was to lie flat on the ground, should never be heeded, since although this action reduces one's height (a good thing), we now know that it greatly increases exposure to possible ground current. Although the NWS has, indeed, recommended the "crouch" as a last resort, the NWS's lightning expert himself, John Jensenius, told me that the advantage is slight--not as great as some NWS websites imply.

However, rather than asking people to focus on appropriate countermeasures when stranded in an open field, the overwhelming theme emanating from Jensenius and the NWS is preparedness and avoidance. When the potential for threatening weather exists, heed the latest warnings and advisories and try to stay out of harm's way. In Jensenius's opinion, few situations warrant squatting or crouching in an open field. More specifically, he says:

  • Plan ahead, including knowing where you'll go for safety;
  • Cancel or postpone activities if thunderstorms are in the forecast;
  • If the trip must be undertaken (during potentially threatening weather), try to insure that the destination is within walking distance of a safe place (hard-topped metal vehicle or substantial building).
  • If thunder occurs, get to the safe place immediately.

With 30-40 lightning days per year here, it is obviously impractical to postpone or cancel events (or attendance at events) every time thunderstorms are "in the forecast." Consequently, one has to make an informed decision based on their percentage chance of occurring.

Personally, with respect to outdoor events, unless the event is canceled, I rarely change attendance plans when there's less than a 40% chance of lightning and, I confess, seldom make changes even at higher percentages. However, I always have "an eye to the sky," and that "safe place" in mind. I will make a better effort in the future, however, to practice what I preach.

How about you? How do you prepare for lightning?

By Don Lipman  | June 16, 2010; 11:00 AM ET
Categories:  Lipman, Thunderstorms  
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Comments

I try to have a car or building nearby if thunderstorms are in the forecast. I'm most concerned about getting caught out in thunderstorms during long hikes, during fishing trips, or when I'm on the Mall to photograph fireworks on the Fourth of July. With the large number of people on the Mall during July 4, there is not enough cover for everyone.

Posted by: Kevin-CapitalWeatherGang | June 16, 2010 11:41 AM | Report abuse

how 'bout adopting this stance (minus the lightening rod in his hand) instead of crouching or lying down? hahaha

http://progolferdigest.com/wp-content/uploads/2008/09/camilo-villegas.jpg

Posted by: walter-in-fallschurch | June 16, 2010 11:53 AM | Report abuse

But with 500k people on the Mall, you've got plenty of other lightening rods. No worries!

Posted by: ah___ | June 16, 2010 2:04 PM | Report abuse

"Lightnin' Fear" is a pretty low priority concern for me. NOAA data shows that "there were 9818 'Storm Data' injuries in the U.S. from 1959 to 1994." During that same period, the number of similar injures in the District: 18. Yes, I said eighteen in thirty-five years.

Here's a link to the data http://www.nssl.noaa.gov/papers/techmemos/NWS-SR-193/techmemo-sr193.html

On average, 70-90 people in the U.S. are killed each year by lightning. In a country of roughly 307 million people, 90 is a rounding error.

I don't mean to convey a wholesale dismissal of weather safety, but more than 100 people are killed each year by road debris.

Crouch, stand, lie down--the chance of becoming a crouton is pretty slim.

Posted by: MRK33 | June 16, 2010 2:46 PM | Report abuse

One more tip: Avoid human lightning rods!

Posted by: spgass1 | June 16, 2010 3:48 PM | Report abuse

spgass1,
hahaha... "sparky"....

Posted by: walter-in-fallschurch | June 17, 2010 8:47 AM | Report abuse

The supposed advantage of the lightning crouch is that there are fewer grounding points. Lying on the ground is supposed to be bad becaue lightning which hits nearby may reach you from the ground.

The best thing to do is to seek a "Faraday cage" such as a motor vehicle or building. Lightning will travel on the outside of a metal surface, but anything inside is protected.

One of the worst things to do is to put up an umbrella, which may convert you into a human lightning rod.

Any drenching downpour, such as what I ran into Monday night is a potential thunderstorm around here. No one is protected from the first strike, but if you hear thunder, you can be struck by lightning. Also, if you hear a loud sudden thunderclap, you were protected--from THAT strike--you never hear the thunder when you are struck!!!

Posted by: Bombo47jea | June 17, 2010 10:38 AM | Report abuse

but seriously, theoretically, would this

http://0.tqn.com/d/golf/1/0/I/D/1/camilo_spiderman_2.jpg

be better than laying down (if he put the putter away) or crouching? he's only touching in 3 small places?

Posted by: walter-in-fallschurch | June 17, 2010 11:40 AM | Report abuse

The comments to this entry are closed.

 
 
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