A severe weather warning for damaging winds has been issued for the Illawarra, South Coast and Southern Tablelands on Thursday.
The Bureau of Meteorology said strong winds are associated with a cold front crossing southern NSW.
Winds averaging 60 to 70 km/h, with peak gusts in excess of 90 km/h, are likely in the Illawarra and northern parts of the South Coast on Thursday morning and early afternoon.
There have been strong winds in the Nowra area overnight and locations which may be affected during Thursday include Wollongong, Nowra, Bowral, Batemans Bay, Moruya Heads, Katoomba, Goulburn, Cooma, Bombala, Thredbo and Perisher.
Emergency services have been called to several locations on the Southern Highlands where trees and branches have fallen on roads.
There is also a strong marine wind warning for Illawarra and Batemans Coast.
The State Emergency Service advises that people should move motor vehicles under cover or away from trees, secure or put away loose items around their house, yard and balcony, keep at least eigh metres away from fallen power lines or objects that may be energised, such as fences.
Fallen power lines can be reported to Ausgrid (131 388), Endeavour Energy (131 003), Essential Energy (132 080) or Evoenergy (131 093).
And for emergency help the SES on 132 500.