At least 81 aged care residents and hospital patients in Goondiwindi are likely to be airlifted to safety with floodwaters lapping just 40cm below the Queensland town's levee bank.
The MacIntyre River is already at its highest level in 10 years at Goondiwindi on Friday with the Bureau of Meteorology forecasting a flood peak of 10.7m within the next 24-48 hours.
Premier Annastacia Palaszczuk says the river is at 10.6m and rising and 81 people in aged care homes and the hospital will be airlifted out if the water gets any closer to the top of the 11m flood levee.
"We'll be monitoring that very closely, we'll be getting another update from the bureau about the flood levels later on this afternoon," she told reporters on Friday.
"Now the people of Goondiwindi understand and they've been through floods before such as 2011, there are some higher grounds that people know where to evacuate to, and we are watching it very carefully and we are keeping the community and everyone updated."
Goondiwindi Mayor Lawrence Springborg said he's confident the levee will protect his town and evacuations by air are necessary due to the circumstances.
"The reason it has to be done by air is because we can't do by road on this occasion as was done in 2011," he told AAP.
"That doesn't mean that those areas are going to flood, it just means that you do this whilst you're very much in control of the circumstances.
"We have a quite a good level of confidence that that levee will again protect our town...we're a very, very well oiled machine when it comes to dealing with this sort of stuff in our preparation and we've just told people in our local community to be in a watch and act situation."
Police Commissioner Katrina Carroll said the airlift is likely to occur later on Friday with the patients to be flown to facilities in Toowoomba and Warwick.
She said State Emergency Services, police and Australian Defence Force personnel were on standby to help ahead of Saturday's flood peak.
The NSW town of Boggabilla, on the MacIntyre's southern bank, is on standby to completely evacuate with major flooding predicted for the border towns along the river in the next 24-48 hours.
Large swathes of the Darling Downs region are awash after days of heavy rain with some areas recording up to 100mm on Wednesday night.
Upriver from Goondiwindi about 110 homes are water-damaged in the town of Inglewood, with 205 homes spared.
Emergency services were forced to evacuate 900 people from Inglewood this week, but the waters was receding on Friday.
Australian Associated Press