The SES received 133 calls for help across parts of the state by Sunday morning including reports of downed trees and branches as well as requests to assist with leaking roofs and water damage.

Some roads in Sydney were affected by flash flooding on Saturday night as significant rainfall fell in parts of the city.

Approximately 100 millimetres of rain was recorded at Point Perpendicular, near Nowra, in 24 hours.

A severe weather warning remains in place on Sunday as a low-pressure system affects the coast between Nowra and Narooma.

SES Assistant Commissioner Nicole Hogan said further rainfall and damaging winds were possible in the next 24 hours in parts of the Illawarra and the south coast.

"The threat from this weather system has not yet passed," she said.

"We are still seeing rain fall and while it will ease during the day, gale winds have been forecast for the Illawarra, Batemans and Eden coastal areas."

The SES said minor flooding was likely at Canowindra early on Sunday morning.

River rises have been detected on the Belubula River and Mandagery Creek.

Australian Associated Press