Residents forced to flee a bushfire threatening homes on the Sunshine Coast early on Wednesday have been allowed to return but urged to remain on alert.

Warnings for the fire burning in national parkland near homes at Peregian Beach on Wednesday morning were downgraded by 2pm (AEST), with the fire contained and under control.

Residents were evacuated after the fire broke out about 6.30am.

Police quickly declared an emergency for an area bounded by Woodland Drive to Stumers Creek Road, David Low Way and the Sunshine Coast Motorway.

About 50 residents in an area bordered by Lorikeet Drive and Greenshank Street were told to leave their homes as the fast-moving blaze bore down on their beachside community.

Huge plumes of smoke also forced the closure of David Lowe Way. on Wednesday afternoon, it remained closed between Tritonia Drive and Emu Mountain Road.

Queensland Fire and Emergency Service regional manager Michelle Young said water bombing helped crews on the ground get a handle on fire, which was estimated to span 100 metres.

She said it was brought under control at 11am and was contained to a small area of bushland to the east of David Low Way.

“All the crews have surrounded the fire, so it’s not going to get away from us,” she said.

“We’ll be on scene for a few hours to make sure we put out all those hot spots and make sure there is nothing in there that can flare up.”

Rural Fire Services area director Andrew Allan said authorities were “taken a little bit by surprise” by how easily the bushfire took hold.

“We did have some rain on Monday night, so very surprising,” he told the ABC.

“It’s all about strengthening those containment lines.

“We’re hitting it with all the resources we can.”

Police Inspector John Lewis said the cause of the fire was not yet known.

“We’ve got [police] investigators on scene, and also fire investigators,” he said.

“When it’s safe and appropriate to do so, they’ll go and look at the area and see if there is any evidence about what may have caused the fire.

“It’s too early to say. We’re not making any predictions on that.”

Queensland Premier Annastacia Palaszczuk remained concerned for the welfare of residents after several homes were lost and bushland destroyed last month.

“After the ordeal of the September firestorm in this area, residents will be worried for their properties,” the Premier said.

Noosa mayor Tony Wellington said it was a difficult time.

“Having been through an extraordinary circumstance just a few weeks ago, only to have all those emotions and concerns re-invoked – it’s not going to be easy for them,” Cr Wellington said.