A complex low pressure is expected to deepen over the Tasman Sea, east of Tasmania. It is expected  to move north-east bringing with it strong south-west winds, which could  reach gale-force in parts of the South Coast and Snowy Mountains districts.

Damaging winds averaging 55 to 65 km/h with gusts of 90 to 100 km/h are forecast to develop in parts of the South Coast and Snowy Mountains forecast districts early on Friday.

Blizzard conditions are forecast to develop for the Snowy Mountains forecast district in areas above 700 metres tonight/early tomorrow morning. Snow is expected on the Central Tablelands above 600 metres and on the Northern Tablelands above 800 metres early tomorrow morning.

Large and powerful surf conditions are expected to develop along much of the NSW coast during tomorrow, hazardous for coastal activities such as rock fishing, swimming and surfing.

The NSW State Emergency Service advises that people should:

- Move vehicles under cover or away from trees.

- Secure or put away loose items around your house, yard and balcony.

- Keep clear of fallen power lines.

For emergency help in floods and storms, ring your local NSW SES Unit on 132 500.