People are being warned not to risk their lives by going to southern Queensland beaches this weekend, with Tropical Cyclone Oma whipping up wild wind and surf.

An earlier cyclone watch for the southern Queensland and northern New South Wales coast was cancelled this morning when the storm weakened to a category one system.

But the Bureau of Meteorology (BOM) warned there would be abnormally high tides and dangerous surf into early next week.

Premier Annastacia Palaszczuk said people should not be complacent.

Wind whips up sand at the Spit on the Gold Coast. ( ABC News: Damien Larkins )

"There could be waves up to 7 metres over the course of the weekend and in some instances it may be higher," she said.

"We don't want to put other people's lives at risk to save you, so please keep off our beaches this weekend.

"My clear message to families from Sandy Cape all the way down to Coolangatta is 'don't go camping, don't go boating, don't go fishing, don't go swimming, and don't go surfing'."

Rough waves off Main Beach at Stradbroke Island. ( ABC News: Heidi Rexa )

The Volunteer Marine Rescue at Point Danger, on the Queensland-New South Wales border, recorded waves of 10.5 metres early this morning.

Lifesavers rescued 43 surfers from Noosa and Mooloolaba on Thursday afternoon.

Sunshine Coast lifeguard supervisor Trent Robinson said many were inexperienced surfers who got in over their heads.

A wave crashes onto onlookers at Snapper Rocks on the Gold Coast. ( Supplied: Grace Riga )

"They just couldn't fight against that sweep and then they drifted out to sea — that wind was a real strong southerly wind and it's even stronger today," he said.

Double the diameter of Debbie

BOM has predicted high tide water levels might exceed the highest tide of the year, particularly at beaches that are exposed to large waves being produced by Oma.

Damaging wind gusts are also predicted along coastal fringe with marine warnings for gales south of Sandy Cape for today and Saturday making boating conditions hazardous.

BOM state manager Bruce Gunn said a flood watch had been cancelled for the coastal catchments south of Gladstone and most rainfall would stay offshore.

People ignore warning signs to check out big waves at the Southport Spit. ( ABC News: Damien Larkins )

"There will be some rain in the south-east of Queensland over the weekend, but not as much as originally foreshadowed," he said.

"Oma is expected to take the south-south-westerly track over the next 24 or 36 hours and then make a U-turn to the north so we're going to keep a very close eye on this cyclone.

"The diameter of this system is huge. It's twice the diameter, about 600km wide, in the extent of strong gale-force winds around the centre.

"Cyclone Debbie by comparison, which was a category three or four system, was only 300 kilometres in diameter but it did have the much more intense winds."

The system is still expected to cause dangerous surf conditions. ( AAP: Dave Hunt )

'That wind's crazy out there'

World surfing champion Mick Fanning was among those making the most of the waves at Snapper Rocks this morning.

"Yesterday the swell came up really quick and today there's some really nice ones but yeah that wind's crazy out there now — it's been fun," Fanning said.

"I think everyone's just frothing out on the waves."

Water flows into Cotton Tree park at Maroochydore as high tide and Cyclone Oma start to impact the coast. ( ABC News: Bruce Atkinson )

A number of beaches remain closed, and boaties have been advised not to go out in open water as crews would not be able to rescue them if conditions worsen.

Bundaberg tour operator Lady Musgrave Experience, which takes tourists to the southern reefs, has brought its fleet into safe harbour.

It also cancelled what would have been its first tourist dives to the shipwreck Tobruk on Monday.

"Probably we've lost about a week in trading at least with the reef run," the organisation's Brett Lakey said.

"As soon as it's abated we're ready to go."

Big swells have washed Rainbow Beach sands into the ocean. ( Supplied: Rainbow Beach Helicopters )

Georgina Kebblewhite, who lives in Bargara near Bundaberg, said she was concerned about the erosion in the region.

"We've seen it like this in Surfers Paradise in the 1960s — that would have been the worst I've seen," she said.

Wide Bay Volunteer Marine Rescue spokesman Bill Ker said the rescue boat would not go out amid the strong wind warning.

"You might be rescued by helicopter and your boat would be had it," he said.

Huge swells caused by Cyclone Oma hit Cotton Tree park at Maroochydore. ( ABC News: Bruce Atkinson )

The ferry to North Stradbroke Island off Brisbane was suspended on Friday.

Holidaymakers at eight Sunshine Coast holiday park sites have been moved away from the seafront due to expected large swells and tides.

The Environment Department said it had no plans to close the Great Sandy National Park, the Cooloola Recreation Area, or the Bribie Island National Park and Recreation Area.

But it warned some campsites at risk of being impacted by storm surges may be restricted.