One person was killed in Katoomba on Thursday night when large tree fell on their car, police confirmed. A second man was freed from the car in a serious condition and was airlifted to Westmead Hospital. He had sustained head and chest injuries.
About 7pm emergency services were called Victoria Street, where they found a sedan underneath a large fallen tree, police said.
Officers found two people inside the vehicle; 40s who had suffered fatal injuries, and the male driver, aged in his 20s, who was trapped.
Officers from the Blue Mountains Police Area Command established in crime scene and commenced inquiries into the circumstances surrounding the incident.
"Friday and Saturday will be windy across much of the state, particularly eastern parts," Bureau meteorologist Gabrielle Woodhouse said.
"The weather warning could be extended to include the Sydney metropolitan area – it's touch and go at the moment."
Sydney will experience a significant drop in temperatures over the weekend, with forecasts of 14 to 16 degrees across the metropolitan basin.
"It is going to be very windy for the next few days [but] by Saturday night we will see an easing trend on those winds," Ms Woodhouse said.
"Overnight temperatures will be very cooler than what we've been experiencing. The windchill factor will make you feel much better – it's a good thing to be rugged up."
While there was decent snowfall on ski fields, with a Perisher receiving 20cm of snow on Thursday, Ms Woodhouse said "strong winds and blizzard conditions could create poor visibility for skiers."
The Bureau forecasts the blizzard conditions will ease during Saturday.
The state could also see snow at lower elevations. Strong winds could create a dust that spreads further to Orange and Oberon, and snowfall is possible in Canberra or the Blue Mountains.
Natassia is a journalist for The Sydney Morning Herald.