Wild surf and hazardous swells continue to tear up NSW's coastline, as surfers and swimmers brave the chill to make the most of the monster waves.

Youngsters in wetsuits lined the edge of North Narrabeen ocean pool today as the huge swell rolled in, while surfers rushed to beaches from Maroubra to Bronte.

On Friday, as the swell began picking up, surfer Kelly Slater was spotted at a Sydney beach taking on the waves, already so ferocious his board snapped.

The huge surf is being driven by a deep and complex low-pressure system hovering above the western Tasman Sea, sending strong south-westerly winds and large waves to much of NSW.

The cold front has seen temperatures plummet in parts of the state with the Blue Mountains at Blackheath, Yetholme and Mount Canobalas and parts of the Central Tablelands receiving a dusting of snow earlier in the week.

The wild surf conditions are expected to last a number of days according to the Bureau of Meteorology, with the swell set to top 5.5m for the rest of the weekend, as gale force winds thrash the east coast.

A hazardous surf warning is in place stretching from Byron Bay down to the Eden coast all weekend, and NSW Police Force, Marine Area Command have urged people to be cautious.

The weekend's ferocious swell of up to five metres will tower the coast, putting oceanfront homes at risk of coastal erosion as beachgoers are told to be vigilant.

People should avoid walking near surf-exposed areas, rockfishermen are warned to avoid coastal rock platforms exposed to the ocean and boaters should consider delaying voyages.

Originally published as Facing down monsters: Mammoth swell hits Sydney