TORONTO -- With wildfires continuing to spread across the U.S. west coast, some parts of Canada are under air quality warnings as smoke travels north of the border.

Environment Canada issued an air quality advisory for much of southern British Columbia Friday as multiple cities reached air quality levels high enough to pose health risks. The warning was extended to include Metro Vancouver Saturday due to wildfire smoke from Washington and Oregon.

“Smoke impacts due to long-range transport from wildfires in the western U.S. have already been observed in some areas of Vancouver Island, the Lower Mainland, and portions of the interior,” the advisory read.

The conditions got so bad that Vancouver was ranked second on a list of cities with the worst air quality in the world, with Portland in first, according to the World Air Quality index.

Smoky skies are expected to continue for 24 to 72 hours and are likely to reach mass impact on Sunday, according to the environment agency. 

“The anticipated smoke trajectory indicates that the areas impacted will grow to the north and east as the weekend progresses with the most widespread impacts expected on Sunday,” the advisory read.

Alberta has not yet been issued an air quality warning. However, weather forecasts expect the province’s air quality to plummet over the next 24 hours. Southern Alberta is expected to notice a difference in air quality by Sunday afternoon. 

Environment Canada’s Air Quality Health Index measures air quality from a scale of one, being a low risk, to 10 being very high risk.

On Saturday, Health Canada posted on Twitter to remind Canadians of the safety guidelines in the event of increasing wildfire smoke. 

Canadians in areas that experience heavy smoke condition are urged to limit outdoors activity, drink water and keep windows and doors of homes and vehicles closed. 

In the U.S. the wildfires have travelled beyond California and have reached Washington and Oregon state. According to NASA’s overview of the fires the smoke has travelled more than 2,000 kilometres and continues to do so as it moves towards the Pacific Ocean.