A significant rain event is underway with “dangerous” levels of moisture and some areas breaking rainfall records that have held for a decade.
Large parts of the nation will be swept by a “significant rain event” over the second half of this week that will bring record-breaking falls and dangerous flooding to many areas.
The Bureau of Meteorology says the heavy band of rain — which is predicted to bring a month’s worth of rain in just a couple of days — has already begun soaking large parts of Queensland and NSW.
The Bureau said the worst of it will be on Thursday and into early Friday and that communities in the northern reaches of NSW will be some of the worst affected areas.
A cold front will move in once the rain clears on Saturday, which could potentially mean snow falls for low-lying regions to the south of the state.
The SES has urged people to think carefully before taking to the roads and for those in the hardest-hit areas to “be prepared” for flooding.
BOM senior meteorologist Jane Golding said the massive wet front was being caused by a tropical air mass being driven by warm waters in Indonesia and northern Australia.
“At the same time we’re seeing a very deep low pressure system over South Australia that’s tracking towards NSW,” she said.
“The combination of these two systems will bring wet and stormy weather to NSW and we’re expecting some very intense rainfall in some areas and potentially some very cold air to follow it.”
Beginning today and carrying on until Saturday the rain in NSW will be “very heavy” at times and, because soils in many areas are already saturated from a wetter than average spring, it is likely to cause flooding.
“We’re expecting this rain to bring riverine flooding, but also some dangerous flash flooding and road flooding,” she said.
She said many areas in the state will see more than 150-200mm of rain in the next few days — with the hardest hit areas predicted to be around the Queensland border. The bureau says “major flooding” is possible around the north west and south west slopes.
“But storms more generally will be a feature across the state, so those dangerous flash flooding type rainfall rates could be seen across many areas,” she said.
“We are looking at a wet and stormy second half to this week. We’re already starting to see the rainfall and we’re expecting that rainfall to increase. Record-breaking rain is likely for some locations.”
Ms Golding added that rainfall records are already being broken by the wet front, with some areas seeing their highest rainfall totals in 10 years.
“Broadly, across NSW many locations will exceed what they usually see in November,” she said. “So it’s a month’s worth of rain in just a few days.”
Assistant Commissioner Dean Storey from the NSW State Emergency Service said some 10,000 members were on standby to respond to the “significant rain event”.
“The message is be aware and be prepared,” he said. “The SES along with our partner emergency service agencies are in a heightened state of readiness. If you live in a flood-prone area, know that risk and plan accordingly.”
He warned that roads across the state may be flooded and cut off.
“Avoid unnecessary travel, stay off the roads if you don’t need to be there, know your local risk and don’t drive into flood-affected areas,” he said.
He said it will be the biggest flooding risk since the major floods back in March.
The good news is that the BOM predicts the heavy rain should clear up by Saturday morning, but it may be followed up cold air and strong winds — which could potentially mean snow falls for low-lying regions to the south of NSW.