Lightning can kill you even if it’s sunny
Thunderstorm safety often comes down to common sense. Do not go out and do not stand under a tree during a thunderstorm. Look for a shelter instead of crouching in a field if there are strikes nearby. And follow the life rule of life 30/30: wait 30 minutes after hearing the last rumble of thunder before going out.
But storms are incredibly dynamic forces of nature, and sometimes it is possible to hear noisy accidents of thunder or see flash lightning when it is completely sunny outside. Although unusual, these apparently thugs and their thunder strikes that accompanies it can spoil the pleasure of summer at best and be at worst dangerous.
“Lightning is known to travel 30 miles from a storm,” explains Cyrena Arnold, meteorologist Popular science. “When this happens, it’s usually when a lot of lightning comes out in the back [of the storm]. “”
‘Blue bolts’
Where there is lightning, a thunder crash is not far behind. If a storm has passed and the sun has returned, it can make lightnings difficult or even impossible to see. Meteorologists call for lightning a “blue bolt”.
According to the National Weather Service, most of these types of bolts are a type of earth lightning, which strikes the storm cloud on the ground below. Lightning clouds to die can occur day and night and is a fairly common type of lightning. However, “blue bolts” are a much less common subtype of lightning cloud. They usually come out of the back of a storm cloud, instead of the front like most lightning bolts. Lightning flashes like these is particularly dangerous, because it seems that they come out of a clear sky.
Lightning moves to the ridiculously rapid speed of light (around 186,000 miles per second), while thunder moves at the speed of sound (about 11,000 feet per second). The way in which light and sound move in the atmosphere affect what we can (and cannot) see or hear during a storm.
Thunder and lightning are both parts of the same event in the atmosphere. Lightning itself is an electricity discharge in a cloud. Lightning heats up the air, making it develop quickly. The expansion creates a shock wave that ends up creating a booming sound of Thunder’s Thunder. Essentially, thunder could not occur without the conditions of the cloud created by lightning.
According to Arnold, it is useful to think of thunder like throwing a stone in a pond perfectly. At the beginning, the initial undulation is very close to the place where the stone was placed. This first undulation will continue to develop until it ultimately disappears.
The sound waves in the atmosphere move in the same way. Thunder and thunderbolt heats up the air, creating large ripples of sound that spread out. While undulations travel in the atmosphere, they dissipate and become softer in the same way as people in the water. So, if you are located near a thunderstorm, it is like being where a stone has been placed in a pond.
“This is why thunder, when it is very close to you, fringe and cracks and is ridiculously noisy,” explains Arnold. “”
The 2017 Megaflash Monster
Lightning and thunder that appears to an unusual point are also linked to one of the most exciting new discoveries in meteorology: the megaflash. In October 2017, only one flash crossed the large plains out of 515 miles. In comparison, the majority of lightning reach less than 10 miles. To be considered a megaflash like this, a flash must reach 60 miles (or 100 kilometers, to be exact). In July 2025, the World Meteorological Organization (WMO) certified that the October 2017 megaflash was the longest lightning flash ever recorded in the United States.
From now on, Arnold and other meteorologists believe that megaflashes like this record occur because of the way the storm is built. These same storm structures could influence blue bolts.
“You are looking at a storm that has a very strong line of grains, or a very strong storm on the front,” explains Arnold. “But behind, he has what I call the garbage.”
The “garbage” behind the initial storm come in the form of stratiform clouds (which indicate instability) and a slight net. The quieter back of the storm can always have an electron imbalance from friction in the atmosphere, but it is not enough to make a lightning strike occurs and balances things. These parts of the storm can be inactive for more than 30 minutes, says Arnold.
As a rule, you will not see a single shot of lightning for a long time, which facilitates the thought that it is sure to return to the outside. But this is not the case.
“What is happening in the megaflashes is that you have a flash that starts in the front part of this storm, where it is more serious. He then returns to this stratiform and triggers a domino effect, ”explains Arnold. “It triggers the load for the entire stratiform [cloud] Section, and he discharges himself suddenly. »»
This resulting discharge is the megaflash, which can lead to many lightnings in one go. The 2017 Megaflash sparked 116 individual strikes in this 515 -thousand long flash.
“ Time is always on our side ”
Lightning kills around 20 to 30 people and injures hundreds of others each year in the United States. In total, 12 deaths were reported to the National Lighting Safety Council in 2024. While the storm season of this year continues, there are several ways to stay safe.
First and foremost, it is always better to wait until a storm has passed before going out.
“Time is always on our side,” says Arnold. “If you are nervous and you wonder if you should come back, do not do it. Find an inner project to do, have a lunch, do something that will pass time. The risk can be low, but if something should happen, the results are really dangerous.”
[ Related: Actually, it’s not safe to crouch during a lightning storm. ]
To follow the standard 30/30 rule for lightning, count the time passing between see lightning and hear thunder. If it measures 30 seconds or less, the thunderstorm is close enough to be dangerous and you should look for a shelter. Then wait at least 30 minutes after the last rumble of thunder and lightning before leaving. If you don’t see any lightning, simply start counting from 30 minutes after hearing the last Thunder rumble as a good rescue rule.
Also listen to some of the nature signals if you come back outside. If your hair is starting to stand up, showing signs of static electricity, or if you feel a tingling feeling on your skin, it is a sign that an electric load is built and you should look for a shelter immediately.
There are also a number of applications you can use to monitor lightning blows in your region, including Myradar, Weatherfront (currently available only on iOS platforms), and a sarcastic application called Carrot.
This story is part of popular sciences Ask us anything series,, Where we answer your most bizarre and burning questions, from the ordinary to the wall. Do you have something you always wanted to know? Ask.
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