Hot, dry conditions and gusty winds have led to what fire watchers call a red-flag warning across northern Alberta's forest as more people were forced from their homes.

Mandatory evacuation orders were issued late Wednesday for the Hamlet of Wabasca and the Bigstone Cree Nation in the Slave Lake forest area.

People were urged to gather at the community of Calling Lake.

Further north, the Chuckegg Creek fire, the largest in the province, was still about three kilometres southwest of High Level, where crews have created a firebreak to protect the community.

"We're still experiencing extreme fire conditions throughout most of the province, including the areas around High Level, and really the rest of the boreal regions of northern Alberta," Derek Gagnon, a provincial information officer, said in an interview.

"We saw some pretty significant fire growth on a number of our wildfires yesterday."

The out of control fire near High Level has grown to 1,500 square kilometres -- an increase of 200 square kilometres from Tuesday.

Gagnon said a new fire around Steen River, which is also in the High Level forest area, grew 170 square kilometres in its first day. People in the settlement were also ordered to leave Wednesday.

Several highways around High Level are closed due to the fires.

Officials said, however, that the firebreak continues to keep the flames away from the town.

About 5,000 people were ordered to leave High Level and surrounding communities more than a week ago. Those evacuees have started to receive provincial emergency funds but have been told not to expect to return home before this weekend.

The red-flag warning, which comes from a fire weather meteorologist, warns firefighters that there's potential for fires to blow up in some areas.

"It's a bit of an alert for our operations staff," said Gagnon. "It's something to pass along to them that says, 'Hey, this is something to look out for because the fire danger conditions are going to be extreme. If you are going to be putting firefighters on the ground, keep in mind that these fires can grow very quickly and spread very quickly and it can put them into danger."'

There were seven out-of-control fires, including the two in the High Level area, burning Wednesday in northern Alberta.

One called the Battle fire in the Peace River area led to an evacuation order Wednesday in the County of Northern Lights. It wasn't immediately known how many people were affected.