Fire agencies and land managers will take advantage of favourable weather conditions over coming days to complete a number of important hazard reduction burns.
Burns at Waterfall will mean lane closures on the Princes Highway between the Princes Motorway and Kurlan Street from Friday until Monday.
A reduced speed limit of 40km/h will be in force plus lane closures: Friday 10am to 3pm; Saturday and Sunday 8am to 5pm; Monday 10am to 3pm.
Expect to see smoke drift across the Sutherland Shire, Southern Highlands, Wollongong, Blue Mountains and Greater Sydney - resulting with air quality potentially reduced.
People in smoke affected areas should avoid outdoor activity, close doors and windows, keep pets in a protected area, remove washing from clotheslines and, if driving, slow down and turn on headlights.
NSW Rural Fire Service Acting Commissioner Rob Rogers said favourable conditions have provided a welcome window of opportunity to complete some key burns.
"These burns are planned well in advance and will help reduce fuel loads and give firefighters a better chance of saving lives and protecting homes in the event of a bush fire," he said.
"It is a challenge striking the balance between completing this important work and not significantly impacting the community and as such, there have already been some burns rescheduled to limit the smoke impact this weekend."
Members of the public are reminded they should only call Triple Zero (000) if they see a fire without a fire truck in attendance.
Asthmatics and people with respiratory or heart conditions should take appropriate precautions, follow treatment and management plans and keep their medication on hand.
Due to an early start to the last bush fire season, only 39 per cent of scheduled burns having been completed so far, meaning the likelihood of a greater number of planned burns expected before next summer.
A full list of scheduled hazard reduction burns, interactive map and further health advice is available at rfs.nsw.gov.au