The south easterly winds in South East QLD today(Australia Day) are being produced by a large high pressure system in the Tasman Sea. This high is dominating weather throughout the south-east coast of Australia today. There is also a low pressure system in the Coral Sea. In the Southern Hemisphere, winds move counter-clockwise around a high and clockwise around a low. So these two systems are both working together to drive strong winds onto the South East Queensland coast.
At the time of this post, winds at Cape Moreton(often the windiest place in SEQLD) are gusting to 69km/h. At this stage it looks like these strong coastal winds are due to hang around for a while. If you’re planning activities that could be affected be sure to check the weather warnings on the BOM website.