Streams and rivulets which could channel run-off.You need at least one body length of horizontal space and half a body length of vertical space Where possible descend at least 100 metres from the summit There are several things that you should consider to make sure you get out of the situation safely. Well, now you’re right in the middle of it and there is thunder and lightning above you already. What should I do in case of a thunderstorm? As a rule you are relatively safe from 20 seconds, as long as the storm is not travelling towards you. This is of course unusual, but still clearly shows how easy it is to misjudge the situation. Lightning can actually precede a storm front by up to 15 km. Now you have a concrete number, and you know how far away the storm is – but how far is far enough? If you think that one, two or three kilometres constitutes a safe distance, you are unfortunately mistaken. When is a thunderstorm dangerously close? Formula for calculating the distance of lightningsĭistance (in km) = (Seconds between lightning and thunder x the speed of sound) / 1000 So the maximum distance is approximately 18 km. But how far away is thunder when you can actually hear it? Sound waves are partially absorbed by the atmosphere. This is a sure sign that you don’t need to worry about the storm yet. There are times when you can see the lightning strikes on the horizon, but there is no sound of thunder. This means that you can do the calculation quite easily by using this simple formula. The idea behind this is that the sound travels one kilometre in around three seconds. If you wait a few minutes and do this calculation again, you can check whether the storm is coming closer or moving away from you. This gives you a rough idea of how many kilometres away the thunderstorm is. When you are out in the great outdoors and have no internet access, you can calculate the distance of a storm using the simple 3-second rule: Just count the seconds between when you see the lightning strike and when you hear the thunder clap and divide this number by three. Evaluating thunderstorm danger in the mountains.What you should do in the event of a thunderstorm.When is a thunderstorm dangerously close?.

Lightning strikes around me