The Bureau of Meteorology is expecting vigorous west to northwesterly winds averaging 80 to 90 km/h to develop south of Wollongong ahead of an approaching cold front that will cross southern NSW on Thursday.

Peak gusts in excess of 120 km/h are possible near alpine areas from Wednesday afternoon and during the night.

From Thursday morning, damaging winds averaging 60 to 70 km/h are expected with peak gusts in excess of 90 km/h.

Another cold front is expected to cross the state between Friday and Saturday with winds only easing after the passage of the second front.

The NSW State Emergency Service advises that people should move vehicles under cover or away from trees, secure or put away loose items around their house, yard and balcony, and keep at least eight metres away from fallen power lines or objects that may be energised, such as fences.

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