That's all the updates on the flooding for now. We'll have more updates across our platforms as the situation unfolds. 

To stay on top of developments, tune into your emergency broadcaster ABC Local Radio.

Mayor Joanna Holden says no evacuation notices have been issued so far, but residents should be prepared to move if they have to when evacuation centres open.

"At this stage, they are predicting, potentially, inundations in a small number of areas in Katherine, potentially to the north, in the northern areas of Katherine," she says.

"But again, it's hard to know – there is a lot of localised flooding at the moment, that we haven't seen previously, so people, regardless of where they are, just need to be prepared.

"To everybody in Katherine, hang in there, we'll get there."

Meanwhile, Katherine mayor Joanna Holden has urged residents "not to panic, but to prepare and plan for what they will do".

"Have a plan in place to reduce the stress and to help you recover on the other side, and stay informed by checking SecureNT, the BOM and ABC radio," she told ABC News Channel.

"Even the ducks have left town, there's that much water around."

Assistant Commissioner O'Brien says evacuation centres are not open yet, but anyone who feels unsafe at home should get out.

"The evacuation centres at the moment aren't open right now, they will be organised to be open this afternoon," he says.

"So just watch out for that messaging in terms of when they are open."

Assistant Commissioner O'Brien says for anyone who feels unsafe before then, "obviously, make some moves now".

"If a local resident feels that they need to move from their home, absolutely move into the town centre, and those centres will be open later today," he says.

Assistant Commissioner O'Brien says critical goods and services will remain available throughout the flooding.

"If we are experiencing or seeing some panic buying at the moment in Katherine, I would urge the Katherine residents, please remain calm," he says.

"You will always have goods in there, we will away be able to get goods in there with our supply chain that we've got at the moment."

Assistant Commissioner O'Brien says sandbags will be available from the NT Emergency Service later today.

"What we want is no panic in the community," he says.

"We do know that water will inundate some localised areas and some low-lying areas of Katherine,but it will not at this time - with the predictions we have from the Bureau - it will not inundate places like the city centre and the major suburbs of Katherine."

But Assistant Commissioner O'Brien says residents should be prepared to leave "in case that messaging comes out for you to move".

"It may come up so quickly that we just want everyone to be prepared," he says.

NT Health deputy chief executive Cecelia Gore says the Katherine Hospital is "being evacuated and will be closed" and is expected to be cut off by floodwaters.

"We are in the process of establishing a mini emergency department in the St John headquarters in Katherine," she says.

"It will be operational by lunchtime today."

Anyone who needs medical attention should call Health Direct on 1800 022 222 or Triple Zero (000) in an emergency .

Shenagh Gamble from the Bureau of Meteorology says the heavy rain has come from a "a low monsoon trough" across the Top End that moved west from the Gulf of Carpentaria.

"This tropical low 31U remains at the base of the Top End and is still expected to bring rather heavy rainfall over the next 24 to 48 hours," she says.

Ms Gamble says up to 250mm of rain has fallen at the Dorisvale Crossing, west of Katherine, with Daly River expected to cop much of the run-off in the coming days.

"As those floodwaters move through the Katherine area and down towards Daly, we will see the Daly River at the police station increase over the weekend, and early next week we expect to reach major flood levels," she says.

Regional Controller James O'Brien says he's asked the chief minister to sign off on an emergency declaration for the Katherine floods.

Assistant Commissioner O'Brien says emergency services have surged resources to Katherine, with the flood level expected to peak at 17.5m later today.

"That may go up to 18.5m or higher, however we are looking at inundation flooding mapping and what that actually means for the Katherine region," he says.

Assistant Commissioner O'Brien says water is expected to move over the Stuart Highway later today, if it hasn't already.

"If it's flooded, don't go in there please," he says.

Welcome to our live moment, this is Jason Walls with you.

I'll be bringing you updates throughout the chief minister's press conference, where Lia Finocchiaro will be joined by Regional Controller James O’Brien and the Bureau of Meteorology's Shenagh Gamble.