A search has been launched for two men missing in New South Wales floodwaters, and evacuations are again at play in the state’s south with more rain on the way.

The missing men are thought to have been riding in the back of a utility swept off the road while being driven across a flooded causeway near the NSW town of Boorowa.

Police say two others in the cab were able to free themselves and get to safety.

NSW emergency evacuations

Further west, where Muttama Creek divides the Riverina centre of Cootamundra, residents have been directed to emergency accommodation at the local showground with dangerous flash flooding a concern.

NSW Emergency Services Minister Steph Cooke told the ABC on Tuesday morning the order was for 10 streets and about 100 homes.

“The weather event we saw come through from late yesterday afternoon and overnight has really caused some substantial damage and wreaked havoc right across the region,” she said.

“It’s a long time since we’ve seen flooding hit the town in the way that it did last night and so people were having to work closely with the SES.”

The Bureau of Meteorology said the Murrumbidgee River at nearby Gundagai was likely to exceed the moderate flood level (7.60 metres) again on Tuesday morning.

It was expected to surpass 8.50m about midday and could reach 9.40m by Tuesday night, bringing the town’s worst floods since 1989.

Evacuations have been ordered and a series of road and bridge closures are also likely.

Downstream at Adelong, the main street is under water and residents in adjoining Selwyn and Tumut streets have been ordered to leave.

An evacuation order has also been issued for Tumut Caravan Park on the swollen Tumut River amid rapidly rising waters and the threat of flash flooding.

There are still more than 80 State Emergency Service hazard warnings current for NSW.

They include evacuation orders for residents along the Murray River at Willow Bend, Moama and Mathoura.

Rainy weather to continue

After some sunshine to round off October, the state faces another rainy month as temperatures drop, the BOM says.

Showers and thunderstorms are forecast across most areas on Tuesday, with creeks and rivers likely to rise rapidly as rain falls on already saturated or flooded catchments.

Following the wet, cold air is likely to sweep Australia’s southeast, bringing chilly temperatures, showers and alpine snow until midweek – all of which are unseasonal for November.

More rain and possibly hail will hit western and southern NSW, with a severe thunderstorm warning for damaging winds and heavy falls for Nyngan, Cobar, Bourke, Wilcannia, White Cliffs and Ivanhoe.

For the next fortnight, above median rainfall (more than 60 per cent chance) is forecast for most of eastern Australia, increasing to very likely (more than 80 per cent chance) for the northeast and far southeastern mainland.

Snow is possible around the Central Tablelands and a light dusting might fall around the Northern Tablelands.