By ERWIN CHLANDA
If you think last Saturday’s “wet microburst” – as opposed to dry – was the beginning of the world’s end, relax: Weather events such as this are in fact “quite common, very regular” according NT based meteorologist Billy Lynch.
What’s more we might get a repeat performance on Friday and Saturday this week.
“A similar weather pattern will move across Central Australia, bringing the risk of further thunderstorms,” he says.
The microbursts are happening this time of the year about every second day throughout Australia, but they are small and localised and so most of them remain unnoticed.
They are more frequent in Central Australia.
This is what makes them happen: Rising air loses two degrees every 1000 feet. Its capacity to contain moisture decreases with height. You can see clouds cut off at their base, all at the same hight.
Mr Lynch says last weekend thunderstorms were developing near a trough over southern NT. They collided with humid air moving in from the tropics to the north-west. An evaporative cooling process set in, similar to what makes our swampies work.
Cold air came down with the rain, which caused the violent burst of winds.
The thunder clouds moved at a speed of about 60 to 70 kmh. The winds they brought along were blowing at least 90 to 100 kmh.
A more accurate speed is yet to be worked out, says Mr Lynch.
The VIDEO was taken by Franca and “Freddo” Frederiksen.