The Northern Territory Emergency Service (NTES) has warned residents in low-lying areas of the coast to prepare a plan for evacuation.
"High tide this evening is forecast to be 6.6 metres at 5.39pm (CST)," a NTES spokeswoman said on Wednesday.
Residents in low-lying coastal areas of Darwin have been warned their homes could be inundated by water as Tropical Cyclone Carlos continues to track north over the Northern Territory coast.
A cyclone warning is now current for coastal areas from Daly River Mouth to Goulburn Island, including Darwin, Croker Island and the Tiwi Islands.
Some residents in the Darwin suburb of Rapid Creek were evacuated on Tuesday night, as swollen creeks damaged roads and caused power outages.
"This high tide, accompanied by possible storm surge, could result in the inundation of low-lying coastal areas such as Rapid Creek, Nightcliff and surrounding suburbs.
"As a precaution, members of the Northern Territory Police Force will be door-knocking this area to advise residents of the high tides over the next 24 to 36 hours."
Much of the water that flooded roads on Tuesday night had subsided by Wednesday morning, as authorities worked to clear debris from overflowing and blocked stormwater drains.
Many people in Darwin's waterfront suburbs were still out exercising and walking their dogs, as they navigated their way around the many large trees that were wrenched from the sodden ground.
Long queues of people waited to get petrol and refill their gas bottles, ignoring calls from authorities to stay off the roads.
Welfare shelters, which are not suitable to use as cyclone shelters, have been opened across the region for people forced to evacuate their homes due to fallen trees and storm surge activity.
A handful of homeless people, commonly referred to in the Territory as "long-grassers", were escorted by police to a pavilion at the Darwin Showgrounds.
David Cunningham, 39, was visiting from an Aboriginal outstation on the Coburg Peninsula and was due to return home when the torrential rain hit, stranding him in Darwin.
"The airport's closed and the roads are blocked," he told AAP.
"The police bought me out here for some food and shelter from the wind."
Kenny Liddy, 42, said he was happy to be at the showgrounds out of the weather, but was waiting to hear more about what transport would be made available to help the Top End's large homeless population prepare for the cyclone.
He said he was concerned power outages and store closures might prevent him and the other Territorians who use the Basics Card, under the federal government's welfare income quarantining scheme, from withdrawing money, purchasing waterproof clothing and food, as well as other essential items.
Mr Liddy has been homeless for several years, and has been living on the streets of Palmerston waiting for a government flat to become available.
"There's no vacant houses here, but I was due to get one soon," he told AAP.
Mr Liddy said he was living rough when a cyclone hit a few years ago.
"It gets your heart going, but I'm not too worried," he said.
"We stay in the car park under the Palmerston Shopping Centre; it's a safe place."
Authorities have indicated plans are in place to relocate homeless people to cyclone shelters, should they be needed.
