Weather Wise: Just how hot is lightning?

Posted at 2:44 PM, Sep 13, 2016
and last updated 2016-09-13 14:44:08-04

CINCINNATI -- This week’s Weather Wise story focuses on lightning, and more specifically, just how hot lighting is.

Jammie J. from Forest Park sent us a photo of a tree that had been struck by lightning. The bolt was so hot that it caused the tree to burst into flames from the inside out.

The air temperature surrounding a single bolt of lightning can reach as high as 30,000 Kelvin, or roughly 53,540 degrees Fahrenheit.

By comparison...

  • Your conventional oven can bake a pizza at 350 degrees
  • Tungsten, the metal with the highest melting point, turns into liquid at 6192 degrees.
  • The surface of the sun pales in comparison to lightning’s heat. It's only 10,340 degrees.

Even so, some people do get struck by lightning and manage to survive, and that has a lot to do with electrical “resistance.”

Since we are essentially giant bags of salt water, we have very little resistance. This allows the electricity from a bolt to flow through us and not generate as much heat. Depending on the exact path, a lightning strike is survivable.

The old tree from Jammie's photo had a much greater resistance and generated much higher temperatures when struck due to friction, which ignited the core of the tree.

So even though lightning is survivable, it’s incredibly hot and also incredibly dangerous to humans, animals and plants.

That’s why we always say: “When thunder roars, go indoors!”