Widespread flooding has hit Mparntwe/Alice Springs after severe thunderstorms caused the Todd River to rise considerably on Wednesday night.
SecureNT issued an emergency warning, the highest level of warning, about 5am Thursday, saying residents need to take action immediately, the NT News reports.
"Any delay now puts your life at risk," SecureNT wrote.
Footage from early Thursday shows fast flowing floodwaters throughout the town.
NT News reported a woman was clinging to a tree in the Todd River after she and another woman were swept away by floodwaters, and NT Police were conducting a rescue operation.
According to authorities, the Stuart Highway is closed from Parsons St to the Ilparpa turnoff. South Tce and all causeways are also closed.
The Local Court in Alice Springs has been closed for Thursday due to flooding.
Alice Springs Airport has reopened and is accessible.
"Travellers should check with their airlines for any flight changes," Airport Development Group said, the NT News reports.
Residents in Desert Springs and Mt Johns suburbs are advised to use the Sadadeen bypass at no more than 40km/hr.
The gauge at Anzac oval is currently 3.3m and increasing, up river Wigley Gorge is 4.5m and appears to be levelling off, this water will move down stream through Mparntwe/Alice Springs.
Many roads could be cut off, including Stotts Tce Bridge and all low level causeways, causing isolation for the residents.
The Gap is now open to traffic in both directions.
Tom Brown roundabout has also re-opened.
Emergency services are responding to multiple requests for assistance, NT Police said.
Police also said Todd River is now receding.
The public are requested to stay out of fast flowing water and to keep any travel to a minimum.
St Phillip's College and the Alice Springs Steiner School have been closed due to the flooding.
Schools will remain open today for children of essential workers and for vulnerable young people and children, Braitling MLA Josh Burgoyne wrote on Facebook, NT News reports.
"Only travel to school if it is safe to do so. If it is not safe, DO NOT travel," he said.
Elsewhere in the Territory, around 300 people from Daly River are being housed at a pavilion at the Darwin Showgrounds due to flooding but it could be many days before they can return home.
Incident controller Gavin Kennedy said on Wednesday hopes of flood levels falling overnight were dashed when a thunderstorm added to flows and increased inundations in the township.
"There are now quite a number of houses where the water is ankle deep ... it's likely by the end of the day they'll be into double figures," he told reporters in Darwin.
Controller Kennedy said it was not expected that water, electricity and the sewerage system would need to be switched off but the town's roads and airstrip were almost completely underwater.
Police on site are flying drones several times a day to monitor the flooding in the township about 220km southwest of Darwin.
A return time for evacuees depended on the waters receding and assessment teams getting in to determine if all was safe, Controller Kennedy said.
with AAP
