Urgent flood warnings have been issued for catchments in western New South Wales as parts of the east coast face another weekend of heavy rainfall, thunderstorms and snow.
A low-pressure system and a cloud band stretching across NSW have combined to bring heavy rainfall to some inland rivers of the state, the Bureau of Meteorology has said.
Showers and rain were expected to hit western NSW from late Thursday, extending to eastern parts of the state during Friday. The rain and thunderstorms are forecast to continue through the weekend, only easing early next week.
Sydney is forecast to see increasing showers and up to 10mm of rain on Friday and Saturday, with minimum temperatures dropping below 10C from Sunday to Tuesday.
Melbourne is also expected to see light showers over the weekend, but will also see minimum temperatures drop to as low as 7C on Sunday.
A cold front and low pressure systems will bring widespread showers and #rain to south-east #Aus in the coming days. This may cause renewed flooding for some inland rivers in #NSW.
— Bureau of Meteorology, Australia (@BOM_au) August 11, 2022
Check latest forecasts and warnings: https://t.co/gkTMGvu1lS and #BOMWeather app. pic.twitter.com/gAh8wLkca8
The cold front has previously moved across Western Australia, bringing isolated thunderstorms, show and rain to parts of that state.
Flood warnings have been issued for the Macquarie, Bogan, Lachlan, Murray, Murrumbidgee and Culgoa rivers, with water levels expected to rise over the weekend.
Approximately 20 to 30mm of rain is expected to fall on Friday around the north-east of NSW, with 10 to 15mm forecast across the Great Dividing Range.
Flood warnings remain current for inland #NSW and north-east #Vic. Rain is expected to return to south-east Australia later this week due to a front and low-pressure system moving across Australia. pic.twitter.com/IvaJKhhsjj
— Bureau of Meteorology, Australia (@BOM_au) August 9, 2022
A severe weather warning for damaging winds has been issued for the Alpine peaks in NSW, with winds averaging 90 to 100km/h and gusts of about 110km/h likely over the region.
Jordan Notara, a senior forecaster at the Bureau of Meteorology, said there was also a risk of storms over western and southern NSW, which could result in localised flooding.
Notara said the rain band across south-eastern Australia was a product of the negative Indian Ocean Dipole, a climate driver that brings greater rainfall to Australia.
“The moisture that we’re actually seeing within that rain band is actually directly associated with that negative Indian Ocean Dipole,” he said.
“So it’s stretching in from all the way across from the tropics [and the] Indian Ocean, across the nation and pushing into New South Wales.”
“And it’s obviously bringing that moisture in from the Indian Ocean into New South Wales and it’s just come at the same time as that low pressure system, which is kind of why we’re starting to see the continuation of these showers.”
Notara said NSW was “primed” for more flooding, especially with some catchments and dams already saturated from previous rain events.
“I think our flood risk is generally high throughout the states due to the climate outlook,” he said. “We’re primed for flooding in the state based on the soil moisture, the dams being full and our climate outlook being one of wetter-than-average conditions.”
