Tuesday's declaration gives authorities additional powers to respond to an emergency, and underscores the unparalleled damage wrought by blazes so far this year.
"This allows the (government) to acquire and deploy the necessary resources to support the management of this unprecedented wildfire season, and protect the health and safety of Northwest Territories residents," the territorial government said.
The Canadian government has approved federal assistance to combat the wildfires and deployed armed forces to help with firefighting efforts in the area.
“We are working closely with the Government of the Northwest Territories to ensure communities have the support they need," Canadian federal Emergency Preparedness Minister Harjit Sajjan said.
The city of Yellowknife also declared a state of local emergency late on Monday to brace for potential risks from nearby wildfires. It was made as a precaution and residents have not been put on an evacuation notice, city officials said.
"Residents should remain calm and ensure they are prepared in the event that the situation changes," Yellowknife Mayor Rebecca Alty said.
Yellowknife is the capital of the Northwest Territories and sits 450km south of the Arctic Circle. With about 20,000 residents, it is one of the largest settlements in the sparsely populated north.
Over the weekend, residents of most communities in the South Slave region of the Northwest Territories, situated along the Alberta border, were ordered to evacuate.
The hamlet of Enterprise, a settlement of just over 100 people, was almost completely destroyed by fire, CBC News reported on Tuesday, quoting Enterprise's mayor.
Wildfires have engulfed parts of nearly all 13 Canadian provinces and territories this year, forcing home evacuations, disrupting energy production, and drawing in federal as well as international firefighting resources.
More than 130,000 square kilometres of land has been scorched - the most on record for this stage in the season - and nearly 168,000 people have been forced to evacuate at some point.
Northwest Territories has so far had 265 wildfires this year, much higher than its 10-year annual average of 185.
