Australia has up to 80 tornadoes a year, but many go unseen

Australia Broadcast Center

a day ago

When most people think of tornadoes, it's probably the striking and terrifying images from Tornado Alley in the United States.
But did you know Australia records anywhere between 30 and 80 tornadoes each year?
The weather events are rarely caught on camera, but earlier this week, several people filmed a tornado as it cut a path across farmland near Frankland River in southern Western Australia.
With winds of more than 120kph, it pinned a farm worker against a fence, flipping his ute and damaging a tractor.
Bureau of Meteorology (BOM) meteorologist Jessica Lingard said there were two types of tornadoes, with one more violent.
"The first are supercell tornadoes and those spawn from supercell thunderstorms, which are the most severe form of thunderstorms," she said.
"They result in our warm season tornadoes [and] usually occur during summer months."
These are the tornado types that appear in the United States, some of the largest and most damaging in the world.
"The other type are non-supercell tornadoes, and these usually occur along the boundaries of two air masses, like a cold front or a sea breeze," Ms Lingard said.
This week's tornado in southern WA was the latter type.
"Australia experiences somewhere between 30 and 80 tornadoes each year, but it is possible that many more tornadoes occur in the more remote and unpopulated parts of Australia and therefore go unreported," Ms Lingard said.
The BOM has recorded rare "tornado outbreaks" in Australia where multiple tornadoes spawn from a single weather system.
On September 28, 2016, seven tornadoes hit South Australia, causing mass blackouts.
"There's no area in Australia that's more prone to tornadoes, but we do experience different areas of Australia having tornadoes under different circumstances," Ms Lingard said.
Supercell thunderstorms, which can produce tornadoes, are most common in New South Wales, Queensland and Victoria, and develop generally in late spring and early summer.
The Enhanced Fujita scale ranges from EF0, the weakest, to EF5.
The Frankland River tornado is believed to have been EF0.
"Each category has a wind speed range and a list of typical damage patterns that we would expect," Ms Lingard said.
She said most tornadoes recorded in Australia were rated between EF0 and EF1.
Ms Lingard said a tornado that hit northern NSW in 1970 was considered the strongest on record.
Known as the Bulahdelah tornado, it reportedly left a 22 kilometre trail of destruction more than 1.5km wide.
"It wasn't officially rated but we estimate from the damage that it was likely to be an EF5 system," she said.
"From all reports, it destroyed 1 million trees, and we also saw a 2-tonne tractor lifted up and thrown on its roof."
The first tornado documented on camera in Australia was in 1911 near Marong in Victoria.
It touched down near the property of a man who happened to have a camera — a rare piece of technology at the time.
There are many kinds of tornado-like weather, and they are different.
"A waterspout is a non-supercell tornado that occurs over water," Ms Lingard said.
"Willy willies or dust devils form on clear days over hot, dry surfaces, and they are rapidly rising hot air, but they are not attached to a cloud over the top."
A "cock-eyed" or "cockeye bob", while commonly thought to refer to a tornado or willy willy specifically, is actually Australian slang for any suddenly occurring storm.
Ms Lingard said there was no evidence to suggest Australia was experiencing more tornadoes.
But she said a growing population, armed with phone cameras, meant the storms that did happen were better documented.
"Everyone's got a camera in their back pocket and access to social media to share these events," she said.
This seems to be a frustration for meteorologists, with the term "mini tornado" often used in the media.
"It's one of those terms that the media love to use. It either is a tornado or it isn't," Ms Lingard said.
It may be surprising news, but Ms Lingard said in terms of tornadoes per square kilometre, the United Kingdom recorded the most.
"Based on land size, the UK gets an average of about 33 tornadoes each year," she said.
But in terms of sheer volume, tornadoes are most common in the US.
"The US obviously holds the title of the country with the most overall tornadoes and the most intense, and they report well over 1,000 tornadoes a year," Ms Lingard said.