Flooding closes regional NSW roads

Flash flooding has forced road closures in parts of NSW, with some rivers expected to peak into the weekend.

Fire NSW and the SES on Wednesday assisted locals in Cootamundra, in the Riverina where some streets were evacuated.

"We have had 42 requests for assistance in the Cootamundra area, mostly for leaking rooves and sand bagging requests," a NSW SES spokeswoman told AAP on Wednesday night.

"Some people have relocated ... but the RSL is open to accommodate them if they need."

There was also flooding in Temora, Stockinbingal, Wallendbeen and Ariah Park and the Griffith City Council has closed numerous roads.

The flash flooding in Cootamundra has started to recede, the SES says.

In total, 12 NSW rivers are subject to flood warnings, with areas around the Lachlan River among the worst affected from recent falls.

An evacuation warning persists for homes in Condobolin, where major flooding is expected when the river peaks at 6.8 metres on Thursday.

Major flooding is also expected in the region when waters peak at Jemalong on Friday, and Euabalong on Saturday and Cottons Weir on Sunday.

The falls follow significant rain and flooding across the state's inland catchments over the past month.