Exceptions remained in Castlegar, which retained a rating of 10+, or 'very high risk,' and Cranbrook and the South Oakanagan, which remained at 'moderate risk.'

A new weather system, bringing moist Pacific air and some showers, is forecast to begin overnight and into Saturday morning.

"Be prepared for possible darkened and orange skies," said Metro Vancouver.

Smoke concentrations may vary across the region, as winds and temperatures change and wildfire behaviour changes.

Residents are being warned of fine particulate matter from U.S. wildfire smoke along with ground-level ozone.

The regional district says the ozone could persist until Monday or longer if hot weather sticks around.

Ground-level ozone is created when pollutants from burning fuel react with organic compounds produced by solvents in sunlight.

Seventy-six local sites provide hourly figures that are processed, stored and posted near real-time on the B.C. air quality website.

Ministry says road dust levels tend to be highest around busy roads and industrial operations.

“Due to the fact the fire has been covered with sand and there are no signs of smoke, the air quality advisory has been lifted."