Australia Weather News

Beaches already hard hit by erosion along south-east Queensland's coast could be further impacted as swells caused by Tropical Cyclone Alfred are expected to cause significant damage.

Hazardous swells are continuing to develop from K'gari to northern New South Wales, with meteorologists expecting more coastal erosion in their wake.

The category two system is expected to make landfall on Thursday somewhere between Bundaberg in Queensland and northern NSW.

However, the weather bureau says it's hard to pinpoint exactly when or where it will cross the coast.

Waves of up to 15 metres and significant erosion are being recorded from K'gari to the Gold Coast.

Bureau of Meteorology spokesperson Sue Oates said they expected destructive winds "in excess of 95 kilometres per hour" as well as "destructive" swells.

"These conditions will continue, and as [the cyclone] tracks further towards the Queensland coast, these waves are likely to be significantly higher than what we're currently seeing.

"The highest recorded wave we have had to this point is 7 metres off the southern Queensland coast."

She said the highest tides and greatest impact were expected to hit on Wednesday night and Thursday morning.

High tides and north-easterly swells in the last week have also made it "uniquely hazardous" in areas close to beaches and dunes, according to Javier Leon, president of the Surfriders Sunshine Coast branch.

"This means that as peak wave heights approach the coast at some stage this Wednesday, the chances of overtopping and flooding are high, especially during high tide," he said.

"Similarly, Bribie Island has been subject to considerable erosion already the last couple of days, with reports of the Happy Valley channel reopening.

"This would have serious implications for places such as Golden Beach, which are now very exposed to wave energy."

If Alfred makes landfall, it will be the first time a cyclone has directly hit the region in more than 50 years.

Beaches on the Gold Coast have been closed, with city officials earlier this week saying they were monitoring eroded areas which could lead to localised flooding.

There may be large and powerful seas from the Seventeen Seventy down to the exposed south-east coast for several days, causing significant coastal erosion, according to the Bureau of Meteorology.

"A protracted period of really powerful swells, and that may result in some quite significant coastal erosion to those exposed beaches," senior meteorologist Felim Hanniffy told the ABC.

Ferry services in Brisbane and the Moreton Bay islands have been halted.

Island and coastal communities east of Brisbane have been told to leave or be prepared for the impending storm.

Premier David Crisafulli said it was "certainly an event that doesn't happen a lot for this part of the state".

"I am asking Queenslanders to be ready for it," he said.