Most of us know that a bushfire can be sparked by lightning from a thunderstorm, but did you know that a thunderstorm can be created by a bushfire?

I'm not a pyromaniac myself, even though I do like fire, but there are some clouds that are – and when they form they get such incredible powers that they can destroy everything in their path. Some of the most extreme bushfires that Australians have endured, like the Black Saturday fires or the Canberra fires, were made significantly worse by the weather that these fires created themselves.

In order to get clouds, you need to get air from the surface high up into the atmosphere. So when you have a bushfire it can heat the air around it and if conditions are just right it can rise up and form a type of cloud called a pyrocumulus.

Now, if conditions are perfect, if the fire's really intense, if the atmosphere is unstable that air can get really, really high, like super-high.

We're talking 1215 km or more, and on its way up to those great heights ice can form and you can get violent winds, and thunder and lightning.

It's all very very frightening. And when that happens the cloud evolves into a type of cloud called a pyrocumulonimbus.

We're essentially just talking about a thunderstorm here, but it's a thunderstorm with a terrifying fuel source at its fingertips.

And when this pyromaniac cloud really heats up, that's when it gets some terrifyingly destructive superpowers, like the ability to hurl burning embers up to 30 km away, or to strike lightning a hundred kilometres downstream from the fire front that can create even more bushfires. They've even been known to hurl down large black hailstones.

One of the most terrifying superpowers of these pyromaniac clouds can get is the ability to make tornadoes. Wait, no, actually scrap that, it's the fire tornado.

That's where you just get a tornado and fire, two of nature's most terrifying things, then just mash them together to get a tornado made of fire. One of the most destructive fire tornadoes we know about was during the 2003 Canberra fires.

Four lives were lost and more than 500 homes were destroyed, but residents knew that it wasn't just a bushfire. When they came home they found cars flipped and trees ripped out of the ground and thrown kilometres away.

Such a large area was alight during the fire and so much energy was released into the atmosphere that during the ten minutes of most intense flaming there was more energy released than during the explosion of the Hiroshima atomic bomb.

All of these superpowers mean that the pyromaniac clouds can create even more destruction and can create even more bushfires, and that means they have the ability to multiply.

They also create incredibly strong winds as gust fronts and updrafts and downbursts and that can make fire move in completely unpredictable ways.

That can put firefighters' and residents' lives in even more danger.

Unfortunately, it can be extremely difficult for the Bureau of Meteorology to forecast these pyro clouds and with the unpredictable way they move and and the complete destruction they can bring, it's best to just be as prepared as possible and get out of their way.

Just out

Move

Shoo

Like just out

Don't even think twice. If you're told to evacuate, move.

Weird Weather: Pyrocumulonimbus

Some of the most extreme bushfires are capable of creating pyromaniac clouds that make them much more ferocious. They’re called pyrocumulonimbus.

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