Ex-Tropical Cyclone Linda's effects are forecast to continue along Queensland's southeast coast until Friday.
The Bureau of Meteorology downgraded the category one cyclone to a sub-tropical low just before 10am on Wednesday.
The system has continued to weaken and is expected to start tracking away from the coastline in the early hours of Friday morning.
The hazardous surf and winds which forced the closure of several southeast Queensland beaches will likely remain on Thursday.
"Beach conditions might be treacherous at least until Friday," meteorologist Adam Blazak told AAP.
Thursday morning's high tide is also a concern and will be monitored by the Bureau, Mr Blazak said.
All Gold Coast beaches were closed on Wednesday while many Sunshine Coast beaches were also shut down including Marcoola, Coolum and Maroochydore.
"It's really important to remember that we don't just close beaches on a whim," Surf Lifesaving Queensland's Jason Argent said.
"If a beach is closed it's because lifeguards deemed the conditions too dangerous, and allowing members of the public into the water would put their lives at considerable risk."
Meanwhile, Queensland's Fire and Emergency Services Minister Craig Crawford said some communities in northwest Queensland could be cut off for up to 10 days following last week's floods.
"There is still a long way to go as far as recovery," Mr Crawford told reporters in Mount Isa.
The Queensland government has also opened a community recovery hub in flood-affected Ingham.
The hub will have staff on hand from government and non-government agencies to offer locals support and advice on recovering from the flooding.