This blog discusses current weather, weather prediction, climate issues, and current events
August 13, 2009
Lightning, the "Crouch", and Joan Baez
I got a call yesterday from one of the organizers of the Joan Baez concert at the Woodland Park Zoo that was held tonight in Seattle. He was worried--the National Weather Service was forecasting showers and thunderstorms during the evening. Thousands of people would be out in the open...with the concert venue in a field surrounding by tall trees and the space filled with metal towers for lighting, sound, and other needs. (Sounds like the scene of some disaster movie!).
How could he keep these people safe? How could they tell whether lightning was approaching? The National Weather Service forecast was for showers and some lightning rolled in late in the afternoon. Their forecast was excellent and the concert started out on the damp side with lots of showers.
Here are some of the things I told him. If you are outdoors in lightning and can't get to safety you need to do two things. First, get away from any tall object--it will attract the lighting. Trees, towers, hills, you name it. It doesn't have to be metal. Just tall. Get at least 100 ft away if you can. Why? Well if lightning hits an object..lets say a tree, the current can reach the ground and spread out along the surface..and can kill up to 50-100 ft away if you are laying on the ground. Or the lightning can jump from a branch directly to you. So keep away from trees. (this was made very real to me while I was an undergrad at Cornell. There was a thunderstorm and a bunch of students gathered under its branches. Lightning hit the tree and most were stunned and several were very seriously, if not permanently, injured).
The second thing to do..the LIGHTNING CROUCH (see above figures). You don't want to lie on the ground..that could be deadly if lightning-induced currents are flowing on the surface. So what you do is to crouch down on your knees with your ankles touching. You can understand why you want to be low...less attractive to lightning, which likes high stuff. By keeping your ankles together, lightning currents riding up one foot will probably pass down the other..thus sparing your vital organs.
It is also recommended that you cover your ears to protect them from the loud sound of thunder. (I know this looks kind of ridiculous, but it works). And if you playing golf--PLEASE--get rid of those clubs and your fancy meta- cleated golf shoes.
I told the concert organizer that if I line of thunderstorms approached it would be best if people retreated to their cars. Cars are very safe...and NOT because they have rubber tires. It is because you are in a cage of metal and the lightning currents will pass around you (I would avoid touching the frame during the storm though).
And keep in mind that lightning can, and often does, strike the same place twice.
When in a thunderstorm you can tell how far the lightning bolt is by counting from the time of seeing the lightning to hearing the clap of thunder...for every 5 seconds you count, the lightning is 1 mile away. 20 second..4 miles distant. You see the lighting flash essentially immediately (since the speed of light is so fast), but sound travels much, much slower.
Well, enough weather safety tips... oil on the road with the first rain in my last blog and now lightning. I don't even want to discuss what happens during the first lightning storm after a dry period...just stay under your covers!
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Hey here`s a lightning question for Cliff or anyone who wants to answer. My grandmaw has sometimes said/ told me "metal is what drawls lighting". I know lighting will strike any tall object it can seek out, but is that statement true, or is that a false of knowledge? Cause back in the early days, I`m betting not a whole lot was know about lightning and how deadly and or dangerous it can be.
ReplyDeleteThe object does not have to be metal..that is an old wives tale.
ReplyDeletewhen we were living in olympia, i took the kids to the fountain to play. I was really concerned about the weather even though no forcast for t-storms, i lived in pullman long enough to know when one was brewing, and sure enough i saw lighting. My kids knew that if I called out lighting, they were to come in immediatly. So when I screamed lighting my kids were the only ones who ran straight to the van. Others looked at me like i was nuts. It was only 15 minutes later one hell of a storm hit and it was just a first of several days of really strong t-storms ( it was in the late 1990's ).
ReplyDeleteIs the crouch avoiding what's known in electronics as the "corona effect"?
ReplyDeletecoronavirus.
DeleteNow see, that is what I thought, Cliff, that it was and is an old wives tale of sorts and they don`t really know much about lightning like we of younger generation do.
ReplyDeleteThe one time lightning struck nearby (about 2 blocks), I had a feeling it was going to happen as my hair stood up for about 20 seconds before it struck. A very distinctive feeling (harkens back to holding onto a Van de Graff generator for a static electricity demonstration)
ReplyDeleteIt might also help us lay folk if you would add what signs or sensations to look for ahead of adopting that lightning crouch, and, once crouching, how long to hold it. Many people have a social aversion to being seen doing something that looks silly, and probably won't hold the pose for more than a few seconds if lightning doesn't strike immediately. Also, there are many people who, because of physical limitations, couldn't hold a crouch for more than a few seconds anyway. Would kneeling with legs together be an acceptable alternative for them?
ReplyDeleteRecap:
1) What clues does one look for to suspect that close-range lightning is imminent?
2) How long should one hold that pose if retreat to a safer location isn't an option?
3) What about kneeling instead of crouching?
Golf shoes nowdays have plastic cleats. Why would they be dangerous in a lightening storm?
ReplyDeleteA relative of mine was shocked after lightning hit a tree several feet from a shed in which she'd taken cover. This was in the South, but if there is lightning it can happen anywhere. Golfers would often get zapped down there. Scary.
ReplyDeleteOnce my Dad was going to go golfing with the threat of lightning lurking. He told me, "It's okay, I'll just use my one-iron. Not even God can hit a one-iron."
ReplyDeleteMetal golf cleats make your shoes a better conductor with the ground. Remember with lighting, being insulated from the ground helps somewhat.... In a direct hit, I doubt it would matter much though.
ReplyDeleteThe UK TV show Top Gear tested the safety of cars in lightening.
ReplyDeletehttp://www.youtube.com/watch?v=ve6XGKZxYxA
Hey folks! Your best lightning safety tip is to read Dan's post above. Paying attention to that "hair standing on end" feeling is your main key to safety. "Crouch" immediately!! You have only seconds! Before a lightning bolt is created, the local electric field must become high enough to ionize the air (tens of thousands of volts per meter). Sometimes, this buildup happens so quickly that there is simply no time to crouch. Also, for folks my age, it's not possible to spend 15-20 minutes in a crouched position waiting for a storm to pass, so you need to know when to "assume the position". So, pay attention to those arm hairs! Also, before a strike corona discharge will occur on high tops of conductive objects around you. At night, you will see a spray of electricity (historically called St. Elmo's Fire) and you best run 50-100 ft. away and "Crouch" immediately! In daylight, you see nothing, but if it is quiet and you are paying attention, you will hear the soft buzzing of the corona discharge appear. Run away from this sound and crouch! Most of the time, we get the advance warning that Dan documents.
ReplyDeleteYes, when your hair stands on end, a lightning strike is about to happen over or near you. Crouch down and start praying!
ReplyDeleteI'm fully aware of the danger that lightning presents, but what the heck? Having lived for more than 26 years in a place where thunderstorms (many of them severe) happen on a regular basis throughout the summer, I never heard of such a thing as crouching during a lightning storm. I went running during storms, sat outside, etc. and really only got scared if there was the possibility of a tornado (which is also not uncommon).
ReplyDeleteRelax, people. You're probably not going to get struck by lightning.
Lightning looks for the greatest concentration of potential.
ReplyDeletePotential gathers most at high or pointed objects.
At the Woodland Park Zoo, there is a very tall water tower (an enormous repository of ground potential) and right next to it is the Norse Home, with lots of pointy corners and antennas. As the most likely lightning targets in the vicinity, I would be extremely surprised if they weren't equipped with lightning rods.
The likelihood of people in the Zoo north field being hit would be pretty small in comparison.
I've heard that lightning actually goes from the ground up. Is that true? It looks like it comes down from the sky to me.
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteBTW: lab studies have shown that a wooden stick is just as likely to attract lightning as a metal pole. Lightning is not that discriminating.
ReplyDeleteAlso this below is from struckbylightning.org from Mike Utley, who speaks with authority as someone who was struck by lightning and has devoted his life to educating others:
Lightning safety has evolved over the years so now when we talk about the 30-30 Rule, instead of standing outside and counting, go inside and count. When Thunder Roars Go Indoors !
The ‘Lightning Squat or Crouch’ is no longer taught since it probably does nothing and give a false sense of security.
5 Levels of Lightning Safety
• Schedule out door activities to avoid lightning.
• Know when & where to be in a safe place. When you hear thunder go to a safe place & stay there for 30 minutes after last thunder.
• Avoid dangerous locations/activities (elevated places, open ares, tall isolated objects) & water related activities ( swimming, boating, near water) DO NOT GO UNDER TREES !
• Last minute risk reduction, including the ‘lightning crouch’ is a joke & probably does nothing at all. THERE IS NO PLACE SAFE OUTSIDE IN A THUNDER STORM
• First Aid: Immediately start CPR !
• If you do not follow the 1st 5, call Coroner & Priest
Source: From Mike Utley's blog struckbylightning.org
Great post, Cliff. One question I've had about lightning and trees and such is if you're on a walk through a forest, you're kind of surrounded by tall lightning rods. What to do then?
ReplyDeleteAnother situation. Last month, I was on the Seattle-to-Portland bike ride, and we were riding out of Chehalis, there was a lightning storm with strikes very close. Our choices were to keep riding through the farm fields, or to go hide by one of the sparse trees. I suppose I could have banged on the door of a farmhouse and begged shelter, but then there were 5,000 other cyclists out that same morning. So we just kept riding... any thoughts?
I was just watching a show on lightning over the weekend(on the discovery channel) and it showed that lighting can come from the ground up. Believe this was via the 'step leader'. But think it usually starts from the thunder cloud and works it`s way to the ground or tallest object to strike. We only see it coming and or appearing to come from the cloud because we cant see it happen in supper slow motion like a camera can.
ReplyDeleteDoes this mean the animals in the zoo with horns will need lightning arrestors installed?
ReplyDeleteWhen you say go indoors, I'm still curious as to what counts as indoors and/or safe?
ReplyDeleteA car is ok because it acts as a cage. Why wouldn't under a metal tower also act as a cage?
A house is ok, but it doesn't really seem like a cage to me. It could be considered a short fat tree.
Real tree is a no no, that seems clear.
Tent, no.
What about under a parmanent metal roof like you might see in the picnic area of a park?
The problem being near a metal tower is two fold...one..lighting can jump from it to you. Second..current can descend the tower and spread out along the surface...and give you a shock if you are nearby...
ReplyDeleteLightning is quite complex...a stepped leader descends from the clouds in a series of rapid steps. It is when the leader is above you that hair stands up. At the same time, upward electrical channels rise from the earth...when they meet a lightning flash occurs.
i was in spanaway/parkland one time and my car got hit by lighting... that was a weird experience!
ReplyDeleteone more thing since larry rice is on here... please do not be so seattle centric with your weather forcasts! We have weather here in centralia/chehalis too!
ReplyDeleteHehehe -- that was funny mainstreeter!
ReplyDeleteI could use more tips on recognizing storm systems from a distance that look to have lightning potential.
Once, hiking near Teanaway, we decided to return to the car after having been checking the plants blooming near a fire lookout. And in the 30 - 45 minutes it took us to drive back down the mtn a torrent of rain and lightning strikes on either side of I90 started booming. I was so grateful we'd left when we had, but sheepish I hadn't made the connection to the weather visible to the West.
Cliff, you forgot the most obvious parallel to your story. Forty Years ago - to the day - Joan Baez performed at Woodstock where the Lightening conditions and concerns were identical.
ReplyDeleteOnce when I was solo backpacking in the Great Basin a large thunderstorm began to move closer and closer. I was in flat sagebrush country, no trees, no low places apart from small, shallow, dry gullies. I ended up quickly hiking back to a small meadow along a stream with rock outcrops rising on both sides and crouched in my tent as the storm arrived and boomed and slung large hailstones (for Oregon that is). I get really scared when I'm alone backpacking and a storm comes! I probably shouldn't have been in my tent, but I really did NOT want to see the lightning and get more frightened. What would have been the best place to be in? Between rock outcrops in a tiny "valley"? Crouching in the open? I'm sure it will happen again because it scares me so much.
ReplyDelete