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Thread: Lightning

  1. #41
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    All, here is an excellent article on "Backcountry Lightning Risk Management" at http://www.pcta.org/wp-content/uploa...ningSafety.pdf. One of the best articles, if not the best. The article is concise--a must read before you go out. You'll be glad you did.

    Keep your head low!

  2. #42
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    Quote Originally Posted by Zuman View Post
    All, here is an excellent article on "Backcountry Lightning Risk Management" at http://www.pcta.org/wp-content/uploa...ningSafety.pdf. One of the best articles, if not the best. The article is concise--a must read before you go out. You'll be glad you did.

    Keep your head low!
    Good article! thanks for sharing. But: Why is that guy in figure 8 squatting on a "useless" foam pad???????

  3. #43
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    Because it's more comfortable and allows you to maintain the "lightning position" longer. The idea is to keep your feet as close together as possible so as not to create a path for current to flow between your legs and through your torso.

    The reason dogs, cows and other 4-legged animals die is because the current enters one set of limbs, goes through the heart and vital organs and out the other - doing max damage.


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  4. #44
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    Quote Originally Posted by magneto View Post
    Because it's more comfortable and allows you to maintain the "lightning position" longer. The idea is to keep your feet as close together as possible....
    Yeah, we get it, I was being facetious. That 1" of "useless" foam can help, despite what has been claimed on here.

  5. #45
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    No worries - my favorite lighting experience happened a few years ago on Mt Monadnock in Jaffery, NH. A typical air mass thunderstorm blew in over the summit and we had wind, rain, fog and thunder and lighting. The summit is completely exposed. I ran off the summit, down into the woods.

    About a half mile down, more hikers were still headed up, despite the storm. One couple had umbrellas. It was raining. They asked about the weather. I said, "there is a thunderstorm over the summit - I wouldn't go up there now - especially not while holding a metal pole over my head." They went on up anyway and I never saw them again.


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  6. #46
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    If you want to learn more about predicting severe weather on your own, there are many "raw data" weather sources available, the best of which is Unisys Weather.

    Take a look at the current "CAPE" plot, CAPE stands for "Convective Available Potential Energy":

    http://weather.unisys.com/upper_air/...ap&inv=0&t=cur

    The CAPE values are a measure of instability and moisture content in the atmosphere. Usually measured in joules per kilogram of air (A joule is an international standard measure of energy expenditure and corresponds to the amount of work that needs to be done to produce one watt for one second), higher values indicate higher moisture and instability, two of the factors needed for severe weather.

    You can also use Unisys to look for sources of lift, like low pressure areas, fronts or mechanical lift from wind blowing across sloping terrain, which when combined with high CAPE values indicates trouble.

    The best thing is all this info is free for anyone who wants it.



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  7. #47

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    This shepherd (I forgot his name), who was spending one hundred days up at the mesa north of Spring Creek Pass, told me when I asked how he handled the storms /lightning in such a opening, "I never seek a shelter, I'm just on my horse back and riding through".
    Well, he's lucky, but at least he had the guts.

    234757qfox3c2wb310d7dw.jpg

    234803vsunzk889kcsd267.jpg

  8. #48

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    "......I don't proceed upwards into exposed areas or leave the protection of large forested areas if the 30/30 rule is broken....."

    I had to look up the 30/30 rule: "go indoors if, after seeing lightning, you cannot count to 30 before hearing thunder. Stay indoors for 30 minutes after hearing the last clap of thunder."

  9. #49
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    Quote Originally Posted by rocketsocks View Post
    this image illustrates quite nicely I think the condition of step or difference in voltages. Attachment 27737

    I appreciate this post and other posts on this thread. All my life, during thunderstorms, I immediately went indoors. So, I never knew much about what has been posted on this thread. Now, I won't have access to "indoors", beginning on today's section hike. Unlike the poor cow, I'll be keeping my feet together. Thanks all, for the education.
    ...with lives on the line where dreams are found and lost
    I'll be there on time and I'll pay the cost
    For wanting things that can only be found
    In the darkness on the edge of town

  10. #50

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    Quote Originally Posted by Vibes Man View Post
    I appreciate this post and other posts on this thread. All my life, during thunderstorms, I immediately went indoors. So, I never knew much about what has been posted on this thread. Now, I won't have access to "indoors", beginning on today's section hike. Unlike the poor cow, I'll be keeping my feet together. Thanks all, for the education.
    Cool have a great hike Vibes man...might get some thunder boomers today too, I dig em! stay safe.

  11. #51

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    Quote Originally Posted by Highway Man View Post
    This shepherd (I forgot his name), who was spending one hundred days up at the mesa north of Spring Creek Pass, told me when I asked how he handled the storms /lightning in such a opening, "I never seek a shelter, I'm just on my horse back and riding through".
    Well, he's lucky, but at least he had the guts.

    234757qfox3c2wb310d7dw.jpg

    234803vsunzk889kcsd267.jpg
    What he didn't tell you is that another shepherd died a few years back doing exactly the same thing. Killed him and his horse both. That was about a mile from the trail where it is near Mineral Creek on a high, exposed meadow.

    http://www.crh.noaa.gov/pub/?n=/ltg/...by_day_00s.php
    Last edited by bearcreek; 07-30-2014 at 14:32.

  12. #52
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    The "Lightning Position" is a last-ditch effort to mitigate a disaster. If you get hit by lightning, even a glancing blow, you will be seriously injured at best. Personally, I'd run away, down the mountainside to the trees, before I'd sit in the lightning position waiting to get electrocuted. I'd only crouch down like that if I felt I was about to be struck in the next few seconds. Otherwise, I'd run.

  13. #53

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    Quote Originally Posted by magneto View Post
    The "Lightning Position" is a last-ditch effort to mitigate a disaster. If you get hit by lightning, even a glancing blow, you will be seriously injured at best. Personally, I'd run away, down the mountainside to the trees, before I'd sit in the lightning position waiting to get electrocuted. I'd only crouch down like that if I felt I was about to be struck in the next few seconds. Otherwise, I'd run.
    how exactly does one know when the bolt is about to hit you? It's funny your handle is Magneto...maybe that has somethin' to do with it.

  14. #54

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    Quote Originally Posted by magneto View Post
    If you want to learn more about predicting severe weather on your own, there are many "raw data" weather sources available, the best of which is Unisys Weather.

    Take a look at the current "CAPE" plot, CAPE stands for "Convective Available Potential Energy":

    http://weather.unisys.com/upper_air/...ap&inv=0&t=cur

    The CAPE values are a measure of instability and moisture content in the atmosphere. Usually measured in joules per kilogram of air (A joule is an international standard measure of energy expenditure and corresponds to the amount of work that needs to be done to produce one watt for one second), higher values indicate higher moisture and instability, two of the factors needed for severe weather.

    You can also use Unisys to look for sources of lift, like low pressure areas, fronts or mechanical lift from wind blowing across sloping terrain, which when combined with high CAPE values indicates trouble.

    The best thing is all this info is free for anyone who wants it.



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    I have always just used high dew points as a indicator...thanks for the link.

  15. #55

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    Quote Originally Posted by rocketsocks View Post
    I have always just used high dew points as a indicator...thanks for the link.
    ...and the AM band radio trick.

  16. #56
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    I'm in the electronics biz - I like X-Men too - so the name stuck.

    You might hear a buzzing sound. As the leader forms, you might notice static charges building up on your body - you hair might stand on end, you might feel as if bugs are crawling on your skin, making you itch. You might see "St Elmo's Fire", which is glowing electrical charges on structures. All of these are signs of an immanent strike. Of course, you might no warming at all.

    Up close (personal experience here) the flash and report will come right together and will sound like an explosion.

    You might also smell ozone after a strike. Remember also that lightning actually prefers to strike the same place twice (resistance of the air does not return right away), so if lightning hits close by, definitely try to get away.

  17. #57

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    Quote Originally Posted by magneto View Post
    I'm in the electronics biz - I like X-Men too - so the name stuck.

    You might hear a buzzing sound. As the leader forms, you might notice static charges building up on your body - you hair might stand on end, you might feel as if bugs are crawling on your skin, making you itch. You might see "St Elmo's Fire", which is glowing electrical charges on structures. All of these are signs of an immanent strike. Of course, you might no warming at all.

    Up close (personal experience here) the flash and report will come right together and will sound like an explosion.

    You might also smell ozone after a strike. Remember also that lightning actually prefers to strike the same place twice (resistance of the air does not return right away), so if lightning hits close by, definitely try to get away.
    oh wow man...some good points there. with regard to the discharge making ozone, I've smelled that while welding, kind of a sweet smell and taste...do you prescribe to the notion the electrical discharge, maybe ozone, or pos or neg ions make a person feel better...I do. do you know if there's any validity there?

  18. #58
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    Quote Originally Posted by rocketsocks View Post
    ...and the AM band radio trick.
    This works - but from a distance. The signs I'm talking about happen seconds before the strike happens.

    When I was piloting older small planes, they were usually equipped with Automatic Direction Finding (ADF) radios that could be used as a form of navigation. These are AM radios, so if you tuned them to the low end of the band, the needle on the display would point toward the lightning. The problem comes when the needle starts pointing all around, as then you are in the storm...

  19. #59
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    Quote Originally Posted by rocketsocks View Post
    oh wow man...some good points there. with regard to the discharge making ozone, I've smelled that while welding, kind of a sweet smell and taste...do you prescribe to the notion the electrical discharge, maybe ozone, or pos or neg ions make a person feel better...I do. do you know if there's any validity there?
    Yeah - the smell of the air after a thunderstorm is invigorating - after the adrenalin rush dies down (and perhaps after a change of underwear).

  20. #60

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    Quote Originally Posted by magneto View Post
    This works - but from a distance. The signs I'm talking about happen seconds before the strike happens.

    When I was piloting older small planes, they were usually equipped with Automatic Direction Finding (ADF) radios that could be used as a form of navigation. These are AM radios, so if you tuned them to the low end of the band, the needle on the display would point toward the lightning. The problem comes when the needle starts pointing all around, as then you are in the storm...
    Cool, used to fly with my Pop grownin' up, he taught me the radio trick.

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