More torrential downpours are being unleashed on rain-weary regions of NSW and Queensland by a large belt of wild weather that has already devastated SA.
Flood warnings are in effect in areas along the Lachlan, Murray, Edward, Bogan, and Darling inland rivers, while flood alerts have been issued for NSW’s north-west, central west, and south-west regions.
The rain band, which is travelling east from South Africa, spans more than 2000 km, which places it between Victoria and southern Queensland.
Over that length, it is expected to drop 20 to 60 mm, which is what SA got, coupled with some significant hail in places like Port Augusta.
The rain, according to Weatherzone meteorologist Andrew Schmidt, was brought on by a low pressure trough absorbing moisture from the Coral Sea.
He said that the easterly winds from the Coral Sea were supplying the country’s current trough with sufficient moisture to enable it to create the storms.
Rain is predicted for the east coast cities, with Melbourne perhaps receiving up to 10mm on Thursday.
Showers are predicted to start in the late afternoon and evening in Sydney and Brisbane.
Ten to twenty millimetres of rain are expected to fall in both cities, but the rain should stop by the weekend.
Sydney will become the wettest city ever this year with only 200 more millimetres of rain.
It has already surpassed the 200mm threshold for the year, which had previously only been done five times in a whole year, and is doing so at an unprecedented rate.
According to Mr. Schmidt, wet Australia was experiencing two consecutive La Ninas, a rare occurrence that occurs when the Pacific Ocean periodically cools and causes rain to fall in the Southern Hemisphere.
We are in a La Nina-like pattern and have this negative Indian Ocean dipole even though we don’t have a La Nina officially, according to Mr. Schmidt.
Therefore, these two climatic factors would suggest that eastern Australia will see a wetter-than-average Spring.
According to Mr. Schmidt, the next summer is probably going to be more rainy than usual.
In the east of the nation, he warned, “we might still experience a wetter-than-average circumstances even throughout summer, or the start of summer.”
The impact of those climatic factors is expected to diminish in the early part of the next year as they return to average.
According to Mr. Schmidt, it is uncommon to have two consecutive La Ninas that closely follow the opposing drying impacts of two El Ninos.
The opposite of La Nina’s rainy season is El Nino.
Since we’ve had two El Ninos back-to-back, drought has affected much of the nation, according to Mr. Schmidt.
The current occurrence of three consecutive La Ninas is unusual.
‘We are seeing more floods which is never a good thing.
‘But in saying that we have witnessed similar tendencies previously.
Two disastrous floods this year have already affected areas receiving the most recent rain.
Large areas of northern New South Wales and southeast Queensland were inundated in February, resulting in estimated damage of $4.3 million.
In July and August, the interior areas of NSW were once again pummelling by rain, resulting in widespread evacuations and further millions in damage.