'Mind blowing': Yarloop fire so hot and fierce, it generated its own weather patterns

Heather McDonald

Experts say they have never before witnessed the unusual weather activity that has fanned a catastrophic blaze in Western Australia.

The fire front, which is moving south west of Perth, has been described as the state’s worst fire disaster in 50 years, after wiping out most of the historic town of Yarloop.

The blaze, which is continuing to spread, was so hot and fierce, it generated its own weather patterns.

If the effects were not so devastating, forecasters might describe it as ‘the perfect storm’ - and there are fears it could happen again.

A thunderstorm formed within the fire system causing lightning that sparked more flames.

“It was a spectacular display of the ferocity and power of mother nature,” said Neill Bennett from the Bureau of Meteorology.

Perth Weather Live captured a time-laspe of the phenomena, filmed from across the Erskine Foreshore, about 40 kilometres from the fire centre.

“It is normally associated with volcanic cloud, you’ll get lightening coming out of those," Steve Brooks from Perth Weather Live said.

"However, because of the size of the forest that’s burning, it has really made it a lot more intense.”

He described the phenomenon as "very mind blowing".

Footage captured by Perth Weather Live showed how the phenomenon developed. Photo: 7 News/ Perth Weather LIve

Here is how it happened.

The heat from the fire was so intense it pushed hot air into the cloud above, causing it to expand upwards.

As the cloud got taller, it developed a flat top called an Anvil, which basically means it was at thunderstorm stage.

Unbelievably, due to the rapidly cooling rising air, ice forms.

The friction between the ice particles sparked lightning.

“That is going to create problems if it starts to send lightening to the ground in areas that haven’t been burnt, you’re going to set up fresh ignition points,” said Mr Bennett.

While the storm within the fire created plenty of lightening, there was little rain to help fire teams in their fight to control it.

Foreboding clouds gather. Photo: 7 News

“Even just a little bit of rain will at least dampen ahead of the fire and give the guys a little bit of a reprieve,” said Steve Brooks.

Neil Bennett said conditions on Friday indicated it could happen again.

The fire front was continuing to head south-west on Friday, as towns including Harvey were evacuated. Photo: 7 News

“Conditions that we saw [on Thursday] to form the cloud are still there and so there is a potential that we could see another one of these clouds developing,” he said.

The Weatherzone Total Lightning Network recorded 91 lightning strikes within a 30km radius of Yarloop in the 24 hours up to Friday morning.

On Wednesday, over 7000 lightning strikes were recorded within that radius.

It is believed one of those strikes started the blaze.