THE Metro Vancouver Regional District announced on Wednesday that it has ended the fine particulate matter Air Quality Advisory for Metro Vancouver and the Central Fraser Valley that has been in effect since September 10.
Air quality has gradually improved but local haze is likely to persist through Thursday, September 15. A more substantial change in the weather is forecast to occur on Friday, September 16 and will further improve air quality. While the advisory has ended for portions of the airshed, fine particulate matter concentrations are still somewhat elevated.
However, an Air Quality Advisory for the Eastern Fraser Valley — which includes the communities of Chilliwack, Agassiz, and Hope — continues because of high concentrations of fine particulate matter, primarily due to smoke from wildfires burning in BC, Washington and Oregon, including the Flood Falls Trail wildfire burning near Hope. Smoke concentrations may vary widely as winds and temperatures change, and as wildfire behaviour changes.
Fine particulate matter, also known as PM2.5, refers to airborne solid or liquid droplets with a diameter of 2.5 micrometres or less. PM2.5 can easily penetrate indoors because of its small size.