The Ministry of Foreign Affairs is urging people to reconsider their travel plans to Brisbane.
It says many of the 150,000 New Zealanders living in Queensland will be affected by the flooding.
New Zealanders who are worried about family members wellbeing should try and contact them directly, but if they can't get in touch with them they can call 0800 432 111.
NZers in flood areas brace for the worst
Many New Zealanders are among those bracing for the worst in Brisbane and other parts of Queensland.
Former West Coast resident Bryn Jones says he's ready to evacuate at a moment's notice.
Sarah Jensen, formerly of Tauranga, says there are a lot of worried people - especially those in lower lying areas.
Imogen Gillions, formerly of Dunedin, who is stranded in Toowoomba, west of Brisbane, says she feels lucky she was not caught in Monday's deadly flash flood there.
The former Dunedin resident says the scene in Toowoomba is of utter devastation.
She arrived there after a camping trip about an hour after the flood raged through the city.
She says cars were washed into poles and couches flushed out of windows.
Ms Gillions says if it had not been for a police officer stopping her and other traffic in a nearby town, she would have caught the worst of the flooding in Toowoomba.
She remains stuck in the city because the highway to Brisbane is closed.
Price also there
Former Warriors rugby league team captain Steve Price was in his hometown of Toowoomba on Monday afternoon.
He was driving home and missed the deluge by about five minutes.
He says his home was not damaged and he feels lucky, considering what other people are having to endure.
Price says many people have come home to see their houses damaged, cars washed down rivers and in some cases relatives missing.