A total fire ban has been declared for the greater Sydney region as abnormally warm spring weather takes hold.

Much of NSW, including Sydney, is forecast to hit 30 degrees over the weekend. Parts of the state’s north-west could reach the mid-30s.

The NSW Rural Fire Service is urging residents living near bushland to prepare their homes and review their emergency survival plans.

It’s been the hottest start to spring in more than 50 years. The last time the city reached higher than 24 degrees in the first few days of spring was in 1969.

Much of NSW is forecast to hit 30 degrees over the weekend. Graphic: Weatherzone

Weatherzone’s Ben Domensino told Nine News that if Sydney reaches 30 degrees on Saturday, it would be only the fifth time on record that a 30-degree day has happened this early in spring.

“In records dating back to 1859, Sydney’s Observatory Hill weather station has only reached 30 degrees three times in August and once during the first five days of September,” he wrote.

Under a total fire ban, all open flames are prohibited and all fire permits are suspended. Gas and electric barbecues may still be used but safety guidelines must be adhered to.

“During a Total Fire Ban you cannot light, maintain or use a fire in the open, or to carry out any activity in the open that causes, or is likely to cause, a fire,” a statement from the NSW Rural Fire Service said.

The ban includes welding, gas cutting, or barbecues and pizza ovens using wood, charcoal, or heat beads, all of which cannot be conducted outside.

Officials warned property owners whose homes are not fully prepared should consider leaving for a safer location. Travellers are also advised to reconsider non-essential trips through high-risk bushland areas on Saturday.

While the fire ban is expected to last 24 hours, NSW RFS warned residents to be prepared for an “incredibly dry” and dangerous fire season.

In a stark contrast, the state’s south is expected to cop snowfall on Saturday. Thredbo’s Top Station, Australia’s highest weather station, could receive snowfall in the afternoon.

Forecasters say an El Nino system will drive temperatures above average across Victoria, Tasmania, South Australia, NSW, the ACT and Queensland.