She and another woman were swept into the swollen Todd River in Alice Springs early on Thursday after storms caused flooding and a warning for residents to shelter indoors.
The Todd overflowed to flood low-lying roads and close all causeways across the riverbed.
Northern Territory Police said officers responded to multiple flood-related incidents across Alice Springs following the rapid rise in water levels.
Around 3am on Thursday police received reports of a woman being washed into floodwaters.
Officers attended to find two women in the water downstream, with one immediately rescued.
An hours-long rescue operation then ensued for the second woman who was clinging to the base of a tree.
"They've got eyes on her, it's just a matter of getting her out of the water now," a police spokesperson told AAP.
One officer who tried to swim to the stranded woman was nearly swept away by the surging water and had to be pulled back on a safety line by other rescue crew, The NT News reported.
After 11 hours the woman was finally rescued, reportedly uninjured.
Police, the NT Fire and Rescue Service and NT Emergency Service have responded to people stranded in floodwaters, vehicles becoming stuck, and reports of flooded homes.
An emergency flood warning for Alice was issued by the NT Emergency Service early on Thursday, saying homes could become isolated by floodwaters which could cause damage to properties.
Residents were warned it was too dangerous to travel and they should shelter indoors until the all-clear was given by authorities.
By late Thursday morning a flood watch and act was in place as Todd River levels receded and children swam in river pools to cool off in the heat.
Emma Collard, a 10-year resident of Alice told AAP she woke up to learn her friend's house had flooded due to the heavy rain overnight, and when she went to the river it was much fuller than she had ever seen it.
"Everyone's out and about this morning chatting ... and there was someone who was saying she's been here about 40 years and she's only seen it like this once or twice."
Ms Collard, 33, said the waters had greatly receded and many people were down by the river "mesmerised" by the river's sudden rise and fall and marking the "special" rain event.
The Alice Springs Local Court was closed but Alice schools remained open for children of essential workers, with parents of other children urged to keep them at home.
Part of the Stuart Highway was closed but the airport has remained open.
Meanwhile the Bureau of Meteorology is forecasting severe thunderstorms across many parts of Queensland on Friday, particularly across inland, central and southern parts of the state.
"Heavy rainfall that could lead to flash flooding is the main concern particularly through central and southeast areas," Meteorologist Miriam Bradbury said in a video forecast.
The risk of heavy rainfall would likely continue through the weekend, she said.
19°C