Northwest Territories Weather

Northwest Territories climate

The Northwest Territories stretches from the 60th parallel to the Arctic Ocean, encompassing subarctic boreal forest in the south and Arctic tundra in the north. Yellowknife experiences a subarctic climate with extreme seasonal variation—winter temperatures regularly drop below -30°C while summer days can reach 25°C or higher. The territory receives relatively low precipitation, averaging around 280 mm annually in Yellowknife.

Winter dominates the NWT calendar, lasting from October through April in the south and even longer in the northern reaches. The polar night brings extended darkness to communities above the Arctic Circle, while summer brings the midnight sun with nearly 24 hours of daylight. These extreme light conditions profoundly affect weather patterns, driving rapid snowmelt and intense but brief summer warming.

Climate change is reshaping the Northwest Territories faster than almost anywhere else on Earth, with temperatures rising at two to three times the global average. Permafrost thaw is destabilizing buildings and roads, wildfire seasons are growing longer and more intense, and the ice road network that connects remote communities is becoming less reliable each year. The territory is on the front lines of Arctic climate transformation.