Northern NSW 'could flood'

Flooding in Coffs Harbour in April 2009.

AAP

AS farmers rejoice after heavy rain in southern NSW, emergency services in the north of the state are gearing up to battle the floodwater run-off from Queensland.

Much of southern Queensland remains sodden after drought-breaking floods.

Cunnamulla, Dirranbandi and Thallon, close to the NSW border, have so far escaped the fate of nearby St George, which was flooded over the weekend as water from last week's deluge heads south.

The Bureau of Meteorology (BoM) says widespread flooding is expected in northern NSW as the water heads south over the border in the coming week.

However, a significant amount will be absorbed naturally by floodplains and artificially by diversions into dams.

"The water does spread out on the floodplain and a lot is lost due to that, and there are also diversions into irrigation dams," BoM spokesman Gordon McKay told AAP.

"We've taken that into account and we're still expecting a large flood in NSW."

He said some small towns near the NSW border may become isolated.

In southern NSW, more rain soaked the region on Monday after the deluge that caused widespread flash flooding on Sunday.

Storms dumped more than 110mm on the drought-hit Riverina in less than a day on Sunday, forcing the closure of sections of the Sturt, Hume and Newell highways.

Major roads have since reopened, the RTA says.

The main railway line between Sydney and Melbourne was also damaged near Junee and XPT passengers had to transfer to buses.

The track was expected to be repaired in time for Monday evening's Sydney to Melbourne service, RailCorp said.

In the village of Ladysmith, east of Wagga Wagga, about 40 residents were evacuated due to the threat of rising floodwaters.

The nearby Kyeamba Creek peaked on Sunday night, but no significant flooding occurred in Ladysmith, allowing residents who left the village to return to their properties on Monday.

However, the rain-filled skies have had a silver lining, with some Riverina farmers saying it's been the best downpour in a decade.

"A lot of farmers have a big smile on their faces today," Primary Industries Minister Steve Whan said on Monday.

But he cautioned the rain was far from drought-breaking, with 65.7 per cent of NSW still officially in drought.

NSW Farmers Association president Charles Armstrong said the timing of the rain was excellent as farmers were on the verge of planting their winter crops.

About 110mm of rain fell overnight at Wagga Wagga, while Narrandera received 73mm and Hillton 60mm.

SES spokesman Phil Campbell said two people in separate vehicles drove into floodwaters and needed to be rescued, while Defence personnel were called in on Sunday in anticipation of flash flooding at Wagga Wagga.