Rescue crews are in for a long night after fierce winds buffeted much of eastern NSW, uprooting trees and sending power lines down.
The State Emergency Service (SES) had received nearly 700 calls for help by Tuesday evening (local time), and the calls were still coming in "quite rapidly" at 7pm.
"There are power lines down, (there are) trees on houses, trampolines on houses," a spokeswoman told AAP.
"They're a repeat offender, trampolines."
The Illawarra and South Coast bore the brunt of the wild weather, with these areas accounting for more than half the calls for help, while the Hunter Valley, Blue Mountains and Sydney were also hit, with gusts at Sydney Airport reaching 82km/h.
Endeavour Energy emergency crews have spent the evening working to restore power to approximately 12,000 homes, mostly in the Illawarra and on the South Coast.
"In the past two hours, we have restored supply to about 7000 customers, however there has been further damage in previously unaffected areas, particularly in the area between Wollongong and Nowra," the utility said in a statement on Tuesday evening.
"At this stage, we are expecting to restore supply to many customers later tonight if the strong winds abate as forecast."
But some families could spend the night in the dark, Endeavour said: "(There may) be customers in outlying areas where we are unable to undertake repairs until tomorrow morning due to the extent of damage caused to our network."
A severe weather warning remains in place and it's expected winds will pick up again on Wednesday.
The Bureau of Meteorology says coastal gale-force winds will ease overnight, before redeveloping on Wednesday morning.
The bureau predicts damaging winds with gusts of up to 90km/h may return to the Illawarra from early on Wednesday, and Sydney and parts of the South Coast may be affected late morning or early afternoon.
The SES said more than 100 emergency crews were still on the ground, and some would work through the night.
"They'll be out there for hours and hours," an SES spokeswoman said.
"But those guys and girls really love what they do, so for them it's a pleasure to be out there helping people."
