A man has died in floodwaters in NSW and thousands of people in parts of greater Sydney have been told to evacuate or prepare to do so as river waters continue to rise.

A police operation retrieved the man’s body on Friday afternoon, he was found in a submerged vehicle in floodwaters at Cobbity, south-west of Sydney, shortly before 8am.

The 68-year-old man is yet to be formally identified. His van remains stuck in the flooded river.

More than 150 NSW schools were closed on Friday after a torrential downpour prompted evacuations in Sydney’s south and south-west.

Residents were ordered to evacuate houses and caravan parks after forecasters predicted major flooding for parts of the state.

Evacuation orders were issued on Friday afternoon for Ebenezer and the northern part of Windsor, even as the rain began to ease. NSW SES acting commissioner Daniel Austin said the risks would remain well after the rain stopped.

“We do expect to see those river levels continue to rise for some time before they start to ease back over the next 12-24 hours,” he said.

“What that really means for us is that we will continue to have flooded waterways and flooded river systems for a number of days yet to come.

“We ask people once again to be really mindful of their situation, their scenario, what is going on around them, and to be across the warnings and the reports from the bureau as to what is actually happening. You need to maintain your level of vigilance.”

Earlier on Friday,  people in Cornwallis and the eastern part of Richmond lowlands were ordered to evacuated, as well as low-lying parts of Cattai, Pitt Town, Pitt Town Bottoms and Agnes Banks.

Residents in Camden and Chipping Norton in Sydney’s south-west and Woronora, Bonnet Bay and Gronos Point were told to evacuate as floodwaters began to rise on Thursday.

People were also warned to prepare for evacuation in Emu Plains, Mulgoa, Sackville North, Pitt Town Bottoms, Camden, Elderslie, Wallacia Weir and North Richmond for fear of being trapped without power and water.

Premier Dominic Perrottet said close to 2400 people were subject to evacuation orders on Friday morning, with more than 17,000 warned to prepare for evacuations.

“Despite the substantial flooding that we’ve seen across our state, what is incredibly pleasing has been that we’ve only lost a very few amount of lives, and that has occurred because of the efforts that everyone has made across our state in following the instructions of the SES,” Mr Perrottet said before the man’s body was discovered.

Emergency Services Minister Steph Cooke said NSW was experiencing flood fatigue but people needed to keep following the advice of emergency services.

“It will stop raining, it will get better,” Ms Cooke said.

“We just need to keep [getting] through this one day at a time.”

The Bureau of Meteorology’s Jane Golding said the rain would ease somewhat on Friday after downpours on Thursday.

“We do have flood warnings current though, so although the rain is easing … we do have major flood warnings for some sites,” she said.

“The rivers will be moving quickly [and] there’s a lot of debris flowing around.”

Mr Austin said the SES had received close to 1200 requests for assistance and conducted 35 rescues in the past 24 hours.

“Across a population base the size that we had under warning areas, 35 is actually quite a low number and we are really grateful for the community for listening,” Mr Austin said.

More than 1200 SES volunteers have been on the ground as catchments react quickly to heavy rain causing flash flooding.

The NSW education department has listed 155 schools, predominantly around Greater Sydney, the Illawarra and Shoalhaven regions that are not operating due to adverse weather conditions on Friday morning.

Major flood warnings are in place for rivers in the Hawkesbury-Nepean Valley and the NSW Central and South Coast.

Water is also spilling over Warragamba Dam, which was at capacity when the downpour started.

A major flood peak above levels seen during the April 1988 floods passed through Menangle on Thursday afternoon, where the Nepean River reached 16.83 metres on Thursday afternoon before falling back to 11.75 metres by 7am on Friday.

Further downstream, the river exceeded March’s height at Camden Weir, reaching 12.21 metres about 10pm on Thursday before falling back to 11.03 metres by Friday morning.

Wallacia is expected to experience flooding at levels higher than last month when the Upper Nepean River peaks on Friday morning.

There is also major flooding at North Richmond on the Hawkesbury River, although the Bureau of Meteorology believes the rises will not be as severe as last month’s flooding.

-AAP