Air quality alert issued for Metro Vancouver and Fraser Valley

An air quality advisory has been issued for parts of Metro Vancouver and the Fraser Valley as air pollution reacts with the warmer weather.

Metro Vancouver issued the advisory saying smoke from a wildfire burning north of Harrison Hot Springs is also occasionally reaching into the Lower Fraser Valley, creating a haze that may also be contributing to the ozone levels.

"That's producing a haze that's affecting visual air quality, but it also can play a role in producing higher concentrations of ozone than we would normally expect," said Ken Reid, the superintendent of environmental sampling and monitoring for Metro Vancouver.

"Right now we're seeing some beautiful sunny hot days and those are the triggers for ground level ozone production."

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The district says high ground-level ozone is formed when pollutants from burned fuels react with the air in the presence of sunlight.

The last time an alert of this kind was issued in Metro Vancouver was 2015.

"Over the last two decades we've seen quite a dramatic improvement in air quality across the Lower Mainland," said Reid.

The advisory is especially aimed at people with chronic, underlying medical conditions.

The forecast for the area calls for temperatures reaching 26 C by Sunday before the weather cools slightly into next week.

With files from Brenna Rose