Communities in inland NSW and the Northern Rivers are being told to prepare for severe storms to lash the region.
Strong winds and isolated falls of between 50 and 100mm are predicted on Thursday night and into Friday.
Broader riverine flooding isn't expected but sudden downpours could bring localised flash flooding and risk from falling trees.
"Our concern is not riverine flooding but we are concerned there will be some flash flooding as a result of the rainfall we are experiencing at the moment," NSW SES Chief Superintendent Greg Swindells said.
With the ground already saturated by several weeks of rain the chance of flash flooding and falling trees is higher.
Emergency services continue to deal with major flooding along the Lachlan River at Condobolin and Euabalong in the state's central west.
Record flooding is still occurring at Hillston and further rises are possible over the weekend.
Further rises are also predicted for Moulamein on the Edward River with access roads in and out of the town closed and residents urged to shelter in place.
"NSW SES is closely monitoring weather conditions and we have moved additional resources into key areas across northern NSW in case they are required," NSW SES Assistant Commissioner Nicole Hogan said.
"The community is urged to prepare, including securing loose outdoor items, moving vehicles away from under trees and make sure your gutters are clear."
Nine SES emergency warnings remain in place as well as 43 watch and act orders.
In the 24 hours to Thursday afternoon the SES responded to 76 requests for assistance and conducted two rescues.
