Newcastle City Council lifeguards have closed beaches from Nobbys to Merewether and are urging extreme caution over the next few days. Stockton Beach remains open.
Large waves generated by Wednesday night's southerly change are expected to be followed by a cyclone swell over the weekend and early next week.
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Sea conditions will be unsuitable for swimming and rock fishing and are best left to professional surfers descending on Newcastle Beach for the Australian Board Riders Battle final this weekend, and Merewether for Surfest.
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Bathers at Newcastle and Merewether Ocean Baths should heed signage before venturing in and chat with lifeguards if still unsure about whether it's safe to swim.
In times of dangerous surf authorities advise that:
- People should consider staying out of the water and avoid walking near surf-exposed areas.
- Rock fishers should avoid coastal rock platforms exposed to the ocean and seek a safe location that is sheltered from the surf.
- Boaters planning to cross shallow water and ocean bars should consider changing or delaying their voyage.
- Boaters already on the water should carry the appropriate safety equipment and wear a lifejacket.
- Boaters should remember to log on with their local Marine Rescue radio base, via VHF Radio or the Marine Rescue APP, and consider their safety management plan.