Northern NSW beaches will feel the force of a cyclone which is tracking off the Queensland coast with dangerous surf and wind conditions forecast over the weekend.
Cyclone Oma is expected to remain offshore and no watch alerts have been issued for the category one storm, but it's causing high winds, abnormally high tides and damaging surf along the northern NSW coast, the Bureau of Meteorology said.
A severe weather warning has been issued from Tweed Heads to Coffs Harbour while a hazardous surf warning is in place for the northern coastline between the Hunter and Tweed Heads.
A powerful north easterly swell is forecast to increase over the weekend which will lead to damaging surf, BoM NSW manager Ann Farrell told reporters in Sydney on Friday.
Beaches from Tweed Heads to Port Macquarie have been closed and are expected to remain closed until early next week.
Surf Life Saving NSW chief operating officer Phil Ayres urged beachgoers to remember if the flags are down, it's not safe to swim.
"The conditions are extremely challenging," he said alongside Ms Farrell.
"It's not only the weight, size and power of the waves but there's a lot of water moving around ... The rip currents both out to sea and lateral to the edge of the beach line are extremely strong."
He urged surfers who see these conditions as a "playground" to not to overestimate their ability and underestimate the power of the ocean.
Rock fishers have also been urged to move to less exposed areas and to wear flotation devices.
"In these conditions it's often rogue waves - even if it looks a little calmer - these rogue waves can come and sweep people off rock platforms," he said.
Cyclone Oma is moving slowly southwards but is expected turn back in a northerly direction on Saturday and remain offshore.
Australian Associated Press