Parts of Narrabri being evacuated on Monday night as town braces for major flooding | UPDATE

The State Emergency Service (SES) has ordered several streets in the town to evacuate, warning of dangerous conditions with floodwater which could encroach on homes and essential services.

Local SES crews have begun doorknocking hundreds of residents which could be impacted by water.

"Due to the new SES emergency warning system implementation, as properties will see water enter on them the NSW SES has to issue an evacuation order," a Narrabri SES spokesperson said.

"We have crews door knocking now, please be respectful as they have been directed to do this."

The following areas across Narrabri Village East, North Narrabri, and South East Narrabri, as well as the industrial area, are being evacuated on Monday night:

The town hit the major flood level of 6.9m on Monday morning and could climb to 7.40m on Tuesday, as the floodwater in the Narrabri Creek moves through town.

"You must evacuate now because properties, roads and essential services are expected to be impacted by dangerous floodwater," the SES said in a written evacuation notice.

"You should evacuate to stay with family, friends, or alternate accommodation in areas unaffected by flooding. If you are unable to find accommodation, an evacuation centre has been set up at the Crossing Theatre in Tibbereena Street."

NARRABRI is bracing for a flood peak more than one metre higher than previously forecast, as homes prepare for major flooding.

The town hit the major flood level of 6.9m on Monday morning and could climb to 7.40m on Tuesday, as the floodwater in the Narrabri Creek moves through town.

Several streets are expected to go under, with emergency services working with locals to prepare homes and any businesses that could be impacted.

A Bureau of Meteorology spokesperson said the peak was revised significantly up to 7.40m based on the volumes of water upstream.

"Now that's a jump of about a metre from our forecast from [Sunday] and that's based on rainfall that fell and the inflows from other tributaries," he told a press conference in Sydney.

It comes as emergency service expect Wee Waa to be isolated for weeks as floodwaters slow across the region.

Acting Controller for Namoi SES Andrew Galvin said there were several helicopters on standby for the Namoi region for emergencies and resupply.

"We have helicopters for resupply, and there are five in this New England region," he said.

"We have the Rural Fire Service, Fire and Rescue NSW and significant SES resources from out of area as well."

READ ALSO:

Mr Galvin said some rural properties would be isolated for weeks because of the slow moving water, as well as Wee Waa with major flooding setting in.

"Wee Waa isolation will continue for some weeks," he said.

"We are doing helicopter resupplies at the moment there.

"We cannot use the Unimog, it is too dangerous for the Unimog there at the moment."

Oxley Inspector Robert Dunn the peak should arrive on Tuesday afternoon, but low lying areas would see flooding earlier.

He said an emergency management centre had been set up to coordinate the flood operations.

"The potential areas that will be inundated, it's just difficult to square that away until we get a prediction," he said.

The Namoi River at Boggabri is likely to peak near 8.50m overnight Monday into Tuesday, with minor flooding.

The Namoi River at Wee Waa at the Glencoe gauge is currently at 7.39m and steady on Monday with major flooding.

The river may reach about 7.50m on Tuesday with major flooding.

Our journalists work hard to provide local, up-to-date news to the community. This is how you can continue to access our trusted content: