The first, a man, was plucked from the rooftop of his house, 15 kilometres east of Moree.

The second, a woman in north Moree, was able to be driven out by SES volunteers.

GALLERY: Flooding on the North Coast

SES incident controller James McTavish said the Mehi River was currently at its peak of about 10.65 metres.

He said there was still a significant amount of water to come from upstream and Moree's main street was expected to flood.

"The 10.65 metres is above the 1976 flood level of 10.59 but below the 1955 level of 10.82. It's not a record but it's still a significant flood," he said.

Evacuation orders are current for Pallamallawa, a township of 600 people to the east of Moree and Biniguy, also to the east.

Four hundred people have registered at the PCYC in south Moree which is being used as an evacuation centre.

Mr McTavish expects "hundreds of homes" have been inundated by flood water.

"We're currently doing an assessment on homes but we expect it to be in the hundreds rather than dozens," he said.

"We're expecting more registrations. A number of people have elected to stay but are realising this is worse than they thought."

Members of the Australian Defence Force arrived in Moree last night on a Hercules C130 with camp beds and stretchers for those displaced by the flood.

It is estimated 10,500 people are isolated across NSW including those areas with current evacuation orders and warnings and areas on the north east coast.

More than 120 SES volunteers are on the ground and 30 Rural Fire Service members.