Strong winds have caused havoc at Sydney airport, where dozens of flights have been cancelled.
A cold front moving over eastern NSW on Saturday has brought damaging winds across Sydney and the NSW alpine region.
Wind gusts reached 76km/h on Saturday morning at Sydney airport where Qantas, Jetstar, Tigerair, Rex and Virgin all cancelled multiple flights.
Virgin warned travellers to watch their flight status for any changes due to the weather.
"We'll do everything to get you on your way as quickly & safely as possible," the airline posted to Twitter.
A severe weather warning for damaging winds remains in place for Sydney, the Illawarra, Southern Tablelands, Snowy Mountains and south coast regions.
There have been more than 300 weather-related call outs to the SES over the past few days across Sydney, the Blue Mountains and the Illawarra, mainly due to fallen trees and power lines.
In Wollongong, part of a roof came off a medical imaging centre and landed near a bus stop on Saturday morning, the SES said.
"No one was injured," SES spokeswoman Carmel Phillips said.
The SES has urged people to pack away or secure any loose items and move vehicles away from trees and power lines.
"The wind today is a little more vigorous than it was yesterday and we are still receiving calls," Ms Phillips said.
The bureau has issued a marine gale wind warning for the Hunter, Sydney, Illawarra, Batemans Bay and Eden coasts.
There is also a chance of blizzards in alpine regions above 1600m on Sunday afternoon.
The NSW National Parks and Wildlife Service recommends back country travel be postponed until conditions improve, the weather bureau said.
Strong winds lashed parts of the state earlier in the week, with Thredbo recording a peak wind gust of 115km/h on Thursday.
A peak wind gust of 96km/h also hit Moss Vale in the Southern Highlands on Thursday.