“Six-hourly rainfall totals of 100mm to 150mm are likely, and locally, heavier falls of about 200mm will be possible,” the bureau said in a warning.
Damaging winds with gusts of about 90km/h were also possible for parts of the coast, whipping up from early Sunday afternoon.
Meanwhile, lifesavers have closed dozens of beaches as a dangerous swell lashes the coastline.
Swimmers, fishers and surfers have been warned of dangerous conditions in Moreton Bay, Sunshine and Gold coast waters, and off the coast at Hervey Bay and Fraser Island.
Surf Life Saving Queensland spokeswoman Peta Lawlor said all Gold Coast beaches were closed on Sunday, as were most on the Sunshine Coast.
“Conditions can be much worse than they look. If a beach has been closed, it has been assessed as unsafe and you should not go in the water,” she said.
“By entering the water, you are not only putting your life at risk, but also potentially the lives of those who come to rescue you.”
Ms Lawlor said conditions were likely to peak on Sunday afternoon and continue into Monday.
“Even if you aren’t planning on going in the water, you’ll need to remain vigilant as beach erosion and coastal inundation is anticipated due to the significant wave heights. Abnormally high tides are also expected,” she said.
Intense falls on the Gold Coast, which saw up to 400mm of rain dumped in parts of the hinterland overnight, have eased a little.
Upper Springbrook recorded 313mm until 1am on Sunday, while Tomewin, just over the border, was doused with 298mm and Currumbin Creek 282mm.
Lydia Lynch is Queensland political reporter for the Brisbane Times