British Columbia

Wildfire smoke to stick around for Metro Vancouver

It may be a new month, but the same old summer wildfire smoke has made a return to Metro Vancouver for the first full week of September.

Cooler weather and showers should bring relief on Friday

People listen to a press conference that discusses B.C wildfire response as smoke from nearby fires is seen through a window in downtown Vancouver. (Ben Nelms/THE CANADIAN PRESS)

It may be a new month, but the same old summer wildfire smoke has made a return to Metro Vancouver for the first full week of September, and it's expected to stick around for a few days.

The thick, low-level smoke moved in from fires in the Interior on Monday night, dropping visibility, bringing back the red sun and causing air quality to deteriorate right across the South Coast.

The culprit has not changed — an incredibly resilient ridge of high pressure that has brought the hot and dry conditions to much of the province since June.

Every time it punches up into the province from the U.S. southwest, bringing the desert heat with it, it also brings a subtle East-to-West air flow that carries the fine particulates towards the coast. The sinking air that comes with the system locks the smoke in across the valleys and inlets.

By not allowing any other weather-makers into the province, the persistent high pressure system over B.C. this summer has led to an incredibly hot, dry and smoky season for the province. (Johanna Wagstaffe/CBC)

Changes in the forecast for the better

There is some good news in the forecast, though  — our smoky high-pressure system is tracking eastward this week. allowing the marine air to return by Friday. 

The front should bring cooler air, clouds and even some rain to the province for the weekend. It's a perfect combination to clear out the smoke for the coasts, and bring some short-term relief for the fires in the Interior as well. 

ABOUT THE AUTHOR

Johanna Wagstaffe

Senior Meteorologist

Johanna Wagstaffe is a senior meteorologist for CBC, covering weather and science stories, with a background in seismology and earth science. Her weekly segment, Science Smart, answers viewers' science-related questions.