Fire Information Officer Lindsay Carnes says conditions are so warm and dry that minor smouldering from lightning strikes over a month ago have grown into fires.
Carnes says those flames were expected to go out with the wet weather that usually leads into the fall.
The latest ban started Thursday and includes the forest districts of Mackenzie, Fort St. John, Fort St. James, Dawson Creek and Vanderhoof.
Carnes says the latest bans, in addition to other fire bans issued earlier, means most of the province is covered.
The prohibitions apply to fireworks and the burning of waste, slash and grass.
Note to readers: This is a corrected story. A previous version wrongly said the ban applies to campfires.
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