What's the best course of action to take if you're camping in the mountains and a thunderstorm strikes?
Interestingly, the average annual frequency of lightning over most of central and northern Scotland is less than five days, compared to 15-20 days in parts of southern England. As such, if you're walking north of the border, hopefully you’ll manage to avoid it altogether. Even if you're in southern England, it's still a fairly rare occurrence. It’s not all good news, though.
The average lightning flash is 2 miles long, travels at over 140,000mph and can reach temperatures approaching 30,000 deg C. Add to that the fact that a bolt can contain over 100 million volts and 100,000 amperes of current, and it’s probably no surprise to learn that a tent offers little protection from a lightning strike.
Let’s start at the beginning – and as with so much – planning and preparation is key. Check the weather in advance, and if lightning storms are on the cards you may wish to reconsider camping at all. Even though the odds of being struck in your lifetime are just 1 in 3,000, lightning kills an average of 3-6 people every year in the UK and injures 30-60 people. Clearly you don’t want to be part of that statistic.
If you still intend to head into the hills you need a safety plan. The truth is that the safest place to be during a lightning storm is in a well-constructed building. A car is also a suitable shelter, but stay away from any metal surfaces inside the vehicle. If you’re within easy reach of a car or building you should be prepared to abandon your camp in the event of a storm.
‘AVOID SEEKING SHELTER NEAR LONE,
TALL TREES OR UNDER ROCK OVERHANGS’
However, most wild camping takes us well away from the beaten track, meaning retreat to civilisation is not an option. Avoiding wide, open spaces or exposed hilltops is obviously a good idea when pitching your tent – anywhere that you are the highest point on the landscape is a bad place to be during a storm. You should also avoid seeking shelter near lone, tall trees or under rock overhangs. Lightning hitting a tree can jump to objects in close proximity, and lightning strikes can arc across openings in rock such as caves or overhangs. If you’re in the way, it’ll go through you. Wherever you pitch your tent the fact remains that once lightning starts, you may be better off outside your tent than in it. While your tent won’t attract lightning as such, a wet tent and metal poles make excellent conductors.
But how do you know when lightning is approaching? Because sound travels slower than light, you’ll see lightning before you hear the thunder that accompanies it. Counting the time between the flash and the clap will give you a rough idea of how far away the storm is; 3 seconds equals 1 kilometre, 5 seconds equals 1 mile. Lightning can travel as much as 10km from the storm, so the general rule of thumb is that if it’s less than 30 seconds between the lightning and the thunder, it’s close enough that you could be at risk. What’s more, nearly half of all deaths caused by lightning strikes occur after a storm has passed. You should assume you are still potentially at risk until 30 minutes after the last clap of thunder. These timing guidelines are known as the 30/30 rule.
‘five out of six people killed by lightning were male’
So, you’ve determined that a storm is approaching but you’re too far away to run to shelter. To give yourself the best chance of not being struck, you should move to lower ground (such as a dry ditch) as quickly as possible, discard any metal objects such as ice axes or poles, and crouch down with both feet close together, tuck your head in and place your hands on your knees. This will lower your height, reduce your exposed surface area and minimise the effect of any electrical charge striking the ground nearby. Do not lie flat – this increases the area of your body exposed to strikes from above or through the ground. If your hair starts to stand on end and metal objects hum or buzz, you should make a swift retreat to another location as a strike may be imminent.
Although the vast majority of fatal strikes kill just one person, nearly one third of lightning strikes causing injuries hit two or more people. Stay at least 5m/15ft away from other people – huddling together increases the risk of being struck and of multiple injuries. As of yet, we mere mortals are unable to accurately predict lightning 100 per cent of the time. But by knowing what to do in the event of a storm you dramatically increase your already favourable odds of not being struck. One final word of warning. Between 1852 and 1999, about five out of six people who were killed by lightning in England and Wales were male. Nobody ever said Mother Nature was fair.
A strike is made up of between 3 and 12 individual lightning ‘strokes’.
There are three different ways of being struck by lightning:
Direct strike: the lightning hits you and goes to earth through you.
Side flash: the lightning hits another object and jumps sideways to hit you.
Ground strike: the lightning strikes the ground then travels through it, hitting you on the way.
About 2,000 people are killed worldwide by lightning every year.
US park ranger Roy Sullivan held a Guinness World Record for surviving seven lightning strikes over 35 years.
On 31 October 2005, 68 cows died on a farm near Dorrigo, Australia when lightning struck the tree they were sheltering under and spread through the ground.
The irrational (eh?!) fear of lightning and thunder is astraphobia.
Lightning myth buster
MYTH There’s no risk of lightning if it’s not raining.
FACT In some circumstances, such as the elevated storms that occur over parts of southern Britain, lightning can strike up to 10 miles away from rainfall. You’ve heard the phrase ‘bolt out of the blue’, right?
MYTH Lightning will never strike the same place twice.
FACT Tall, pointy places are always going to be high on the list of lightning’s preferred destinations and will often be hit regularly. The Empire State Building is hit nearly 25 times a year, and while that number may be much lower for hills and mountains, anywhere with a history of strikes is best avoided during a storm.
MYTH Wearing shoes or boots with rubber soles will protect you from lightning.
FACT The lighting strike will have travelled up to 3 miles at speeds of over 140,000mph. A few millimetres of rubber on your feet will make no difference whatsoever.
MYTH Don’t touch somebody who has been struck by lightning – they could still be electrified.
FACT Not only will they carry no electrical charge, they will almost certainly require medical help. Dial 999 and summon the ambulance service. If you know how, you may be required to administer CPR if the victim has suffered cardiac arrest.
For more information on lighning and how it's formed visit: