A wildfire near Whitecourt has grown in size overnight causing crews to work hours on end to contain the blaze.

Fire officials say on Wednesday night the fire crossed Highway 32, about six kilometres north of the Highway 32 and Highway 43 junction. By Thursday morning, the fire now covers 475 hectares.

Officials with Sustainable Resources Development gave CTV News a fly-over of the area, showing damage done to land that supplies the province with timber.

Strong winds have made the fire-fight difficult for crews.

Just after 10:30 p.m., crews were forced to close Highway 32 to traffic. But it has since been re-opened. Still, motorists are being advised to take alternate routes due to concerns that smoke could reduce visibility in the area.

The cause of the fire is still under investigation, but officials believe this was human caused. 

Strathcona County has already instituted a full fire ban until further notice.

The ban applies to all rural areas, hamlets and Sherwood Park. The County has called the ban in response to the extremely dry and windy conditions.

With files from Jessica Earle