Wild weather and heavy snowfalls have led to more than 20 crashes on NSW roads, left thousands without power and closed about 50 schools.
Chief Superintendent Simon Locke said snow is causing major problems for emergency services.
"Snow, ice, strong winds and heavy rain are making for treacherous conditions for NSW Ambulance paramedics to respond to patients," he said.
Paramedics have responded to more than 20 car crashes since 5am on Friday morning with the education department listing 48 schools shut due to the weather.
Up to 2200 homes and businesses in the Blue Mountains and Southern Highlands are still without power and are not expected to be reconnected until late on Friday afternoon.
The towns of Blackheath, Bowral, Berrima and Katoomba are among those hit by the power outages.
Power has been restored at more than 6000 premises in snow-coated parts of NSW.
Road closures are in place in Sydney, Lithgow, Bathurst, Katoomba and other areas in the Blue Mountains.