The Sunshine Coast Regional Council is urging residents in low-lying areas to prepare for possible flash flooding, with heavy rain forecast in south-east Queensland over the next two days.
The weather bureau says up to 200 millimetres could fall across the region in the next 24 hours.
Alan Rogers from the local disaster management group says periods of intense rainfall and strong wind gusts are also expected.
"This system could bring a significant amount of rain and with it once again we could have local flooding," he said.
"The reality is that the weather is the weather and it's unpredictable and we don't know how much rain is going to fall today.
"It could well fall - and this is what's causing us some concern - fairly heavily for a few hours and we don't know what time that is."
Five Sunshine Coast beaches will be closed today - Buddina, Maroochydore, Alexandra Headland, Mudjimba and Discovery.
Lifeguard supervisor Reece Drury says swimmers should be cautious.
"It's a pretty horrible day down here on the beach - we've got around three-to-four- foot of swell," he said.
"The winds are quite strong from the east-north-east and they'll get stronger as the day goes on.
"We've got a lot of strong water movement around today.
"We've also got a lot of erosion still from the last big swell that we've had
"A few beaches will be closed due to this erosion."
© ABC 2013
12:32 EDT Fishermen in the Gulf of Carpentaria are hopeful Tropical Cyclone Gillian will bring heavy inland rain, flushing out rivers to provide food for ocean fish stocks.