Regional officials issued an air quality advisory Friday for eastern Metro Vancouver and the Fraser Valley due to ground-level ozone and the potential for wildfire smoke to arrive on the south coast in the coming days.
Metro Vancouver said high concentrations of ground-level ozone are expected to persist “for the next couple of days during the hot and sunny weather.”
Additionally, modelling suggested that wildfire smoke from fires burning in the B.C. Interior could arrive in the Lower Mainland by early Saturday morning and persist through Sunday. Onshore winds forecast to arrive by Monday will help clear the smoke, it said.
“Smoke concentrations may vary widely across the region as winds and temperatures change, and as wildfire behaviour changes,” Metro Vancouver said in its advisory.
Ground-level ozone is created when pollutants from fuel combustion mixed with volatile compounds emitted by solvents and other materials react in sunlight.
It is at its highest concentrations between mid-afternoon and evening on summer days, and is of most concern for people with chronic illnesses such as lung or heart disease, COPD, bronchitis, emphysema and asthma.
Children, pregnant women and seniors, as well as people with respiratory illnesses including COVID-19 are also at risk.
Lower Mainland residents are being urged to avoid strenuous activities, particularly later in the day.
Metro Vancouver is also urging people to stay cool and hydrated, and look to tools such as air conditioning and portable air filters.