Hair suddenly standing straight up? Take cover immediately
"This is Nature's final warning."
If you spend a lot of time on social media, you may have -- or might in the future -- come across a video featuring people outside with their hair standing straight up.
These "static hair" videos often go viral for their novelty, but they could be a sign of imminent danger.
"If you feel your skin begin to tingle or your hair standing on end, this is due to the rapid build-up of static charge," reads a statement on the U.S. National Weather Service (NWS) website.
"This is Nature's final warning [of an impending lightning strike]. However, this is not a reliable indicator, as many lightning strikes occur with no warning. If this happens, seek shelter immediately. DO NOT lie flat on the ground."
What causes static hair?
"Lightning is caused by a static build-up of charge between particles within a thunderstorm cloud," explains Weather Network meteorologist Kelly Sonnenburg.
"The particles become distributed amongst different levels within the cloud depending on their weight.
While this distribution is happening above, at the surface of the earth, a collection of charged particles begins to build. This can be on the ground, on objects, or in some instances, on humans."
Charge builds on the earth, and opposite charge builds in the clouds.
"These charges look for a way to meet one another because opposites attract," Kelly says.
"The attraction between the electric particles within the thunderstorm cloud and on the surface of the earth or human build a static charge which begins to 'pull' towards one another and in some instances, results in people's hair beginning to rise."
Kelly experienced this firsthand when she was younger.
"I was near a lake," she says.
"A thunderstorm was building and approaching, but the winds were calm. We noticed hair strands starting to rise on one another's heads and on our arms. This was a quick indication that danger was nearby, and it was time to head indoors."
Lightning facts
Lightning is hot. Really hot. A lightning bolt can heat the air around it to make it five times hotter than the surface of the sun.
There are approximately 100 lightning strikes every second globally. That works out to about 8 million lightning strikes a day.
Canada sees an average of 2.25 million lightning strikes per year.
Lightning safety tips
Stay away from windows.
Unplug appliances.
Avoid running tap water -- lightning can travel through pipes.
Try to reach a safe building or vehicle (picnic shelters, dugouts, and sheds are NOT considered safe).
Avoid high ground, water, tall, isolated trees, and metal objects such as fences or bleachers.
If you are out on the water, get to land and find shelter immediately.
If someone is struck by lightning
Call for help / dial 911. The injured person has received an electrical shock and may be burned or have other injuries.
People who have been struck by lightning do not retain an electrical charge and can be handled safely.
Give first aid.
If the heart has stopped beating, a trained person should give CPR.
Environment Canada offers a 30-30 rule. If you can count 30 seconds or less between seeing a lightning flash and hearing the thunder, take shelter and stay there until 30 minutes after you last hear thunder.
Header image: Cropped stock image for illustration purposes only. Sourced from Canva Pro.